Seroprevalence of toxoplasmosis in France: first study in blood donors

Seroprevalence of toxoplasmosis in France: first study in blood donors | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Seroprevalence of toxoplasmosis in France: first study in blood donors Lya Hamet, Angélique Bonnet, Jean-Pierre Gangneux, Florence Robert-Gangneux This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8896387/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract The seroprevalence of toxoplasmosis is well-described in French pregnant women, but no data are available in the general population. This study investigated 1,995 blood donors (sex ratio = 1), aged 18 to > 70 years (mean 44.8). The seroprevalence was 51% and increased with age, reaching almost 90% in patients > 70. Men exhibited a higher seroprevalence than women in age group 30–39 (41.1% vs 27.6%, p < 0.05). Multivariate analysis confirmed that men were more likely to be infected than women (OR = 1.234, p < 0.05). The highest prevalences for Toxoplasma were observed in the Northern and South-Western regions of France (55.2 to 60.5%). The lowest prevalence was observed in the East (41.4%), and was significantly higher in men < 40 years. These data are consistent with prevalence studies conducted in French pregnant women, but shows for the first time that females are less frequently infected than male, particularly in some regions, which could motivate further epidemiological investigations. Toxoplasmosis Toxoplasma gondii serology seroprevalence blood donors Figures Figure 1 Figure 2 INTRODUCTION Toxoplasmosis is a cosmopolitan zoonotic infection caused by an intracellular protozoan, Toxoplasma gondii [ 1 ]. Cats and other felids are the definitive hosts of the parasite while humans, as well as all warm-blooded animals, are intermediate hosts. Toxoplasma is transmitted through the ingestion of water, food or soil, contaminated by oocysts which have been previously spread into the environment by felids faeces. Intermediate hosts then undergo go a systemic dissemination of tachyzoites through the blood stream, resulting in the persistence of encysted parasites in muscles, brain and eyes. As a result, infection can also occur through the ingestion of undercooked meat of intermediate hosts harbouring tissue cysts. Primary infection with Toxoplasma gondii in human is usually benign or asymptomatic in healthy individuals, except when patients are infected with a virulent genotype strain. By contrast, toxoplasmosis is a life-threatening infection in immunocompromised patients, such as HIV-infected patients or transplant patients. It can also be acquired through transplantation to a naïve donor of an infected organ containing cysts, or through blood transfusion if it contains tachyzoites [ 1 ]. Vertical transmission to the foetus can happen when toxoplasmosis is acquired during pregnancy, a situation where tachyzoites disseminate through the bloodstream and pass through the placental barrier. It is estimated that one third of the population is infected by Toxoplasma gondii , but the seroprevalence varies widely between countries from 10 to 80%, and sometimes within a given country [ 2 ]. Low seroprevalence, below 30%, has been observed in North America and Northern Europe, South East Asia and the Sahelian region of Africa. In Central and Southern Europe prevalence is usually moderate (30–50%), while high prevalences have been reported in warm and humid areas such as Latin America and tropical African countries [ 1 , 3 , 4 ]. In developed countries, contamination seems to be essentially linked to the consumption of infected meat [ 5 ]. In Europe, prevalence varies according to dietary factors, as prevalence is lower in countries where meat is eaten well-cooked (UK, Scandinavia), and higher in France due to the consumption of rare or smoked meat. Several studies have focused on the seroprevalence of T. gondii among pregnant women [ 6 – 10 ], but this specific group is not representative of the French population as a whole. To the best of our knowledge, no seroprevalence studies have focused on French blood donors. Therefore, this study aimed to estimate the prevalence of toxoplasmosis in blood donors, to complete French epidemiological data. MATERIAL AND METHODS Sample collection This is a retrospective study conducted at Rennes University Hospital (Rennes, France), aiming at assessing the seroprevalence of toxoplasmosis in French metropolitan blood donors. Sera were obtained through donation by the blood French establishment (Etablissement Français du Sang, EFS) before destruction. Sera were collected from adult patients during blood donation and stored for usual serologic screening to secure blood-derived products. The donation to Rennes University Hospital consisted of all sera collected in all French regions, overseas territories excluded, between July 1st and December 31st 2019. For each serum, available information was: sex, age range by decade (as the date of birth was not precisely known), and department/region of France where blood donation took place. Serological tests All sera were included in the study and tested for anti- Toxoplasma IgG and IgM antibodies using the Platelia® Toxo IgG and Platelia® Toxo IgM (Bio-Rad, Marnes-la-Coquette, France). In case of doubtful results for IgG (IgG titer in the range 6–8 IU/mL) and/or doubtful or positive IgM (IgM index in the range 0.8-0.999) using these kits, a confirmation technique was performed, using the VIDAS® Toxo IgG II and VIDAS® Toxo IgM (BioMérieux, Marcy-l’Etoile, France), respectively. When IgG remained doubtful with both previous techniques, a western blot (WB) was performed using the Toxo II IgG confirmation kit (LD Bio Diagnostics, Lyon, France), and interpreted according to the manufacturer’s recommendations. All IgM-positive sera with simultaneous IgG detection benefited from an IgG avidity assay using the VIDAS® Toxo IgG Avidity kit (BioMérieux). A high avidity ≥ 0.300 can exclude primary infection within the last 4 previous months, while low avidity < 0.200 may suggest recent infection with T. gondii . An intermediate avidity between 0.200 and 0.299 is inconclusive. Toxoplasma infection was defined by the presence of specific anti- Toxoplasma IgG with or without specific IgM. Statistics The mean age of the study population was calculated by multiplying the number of patients by the midpoint value of each age category, divided by the total number of patients. Prevalences were compared across categories (age class, sex, region of residency) using a Chi-squared test, or a Z test (age class, sex). Statistics were made using GraphPad Prims v10.1 software. A multivariable logistic regression model was then performed to estimate adjusted odds ratios (ORs) and their 95% confidence intervals (95% CI). The reference categories were 18–29-year-old, female, and Grand-Est, for age, sex and region, respectively. Statistical significance was assessed using a two-sided threshold of p < 0.05. Model fit was evaluated using the likelihood ratio test and McFadden’s pseudo-R². Multivariable analysis was performed using Python, with pandas library for data management and statsmodels for statistical modelling. Ethics approval Blood donations are made voluntarily to the EFS, and donors give their consent for their use, including serological testing. The study adhered to the Declaration of Helsinki. Samples are anonymized and only a few data remain associated to the sample. Additionally, the study was approved by the ethics committee of the University Hospital of Rennes (approval number #25.153), which waived the necessity to inform patients of the reuse of their blood for secondary study, in relation to the strictly anonymized process and to French regulation (article L. 1211-2 du Code de la Santé Publique). RESULTS In total, 1,995 sera were collected from healthy blood donors from the 12 regions of France. Platelia® Toxo IgG were positive and doubtful in 1,010 and 8 cases, respectively, while Platelia® Toxo IgM were doubtful or positive in 173 sera (8,7%), thus needed to be confirmed by VIDAS® Toxo IgG or VIDAS® Toxo IgM. Thirty-two IgM and 5 IgG results were confirmed positive or doubtful with VIDAS® (sup. Table S1 ). Three sera with doubtful IgG results with both techniques were confirmed positive using the WB. An IgG avidity test was performed on all sera with positive IgG associated with positive or doubtful IgM (n = 32), of which 26 (81%) had high IgG avidity (infection dating more than 4 months ago), 4 had low IgG avidity and 2 were in the grey zone, thus recent infection could not be excluded. Overall, of the 1,995 blood donors, 51% (n = 1,015) had IgG antibodies against Toxoplasma gondii (IgG+/IgM-, n = 983; IgG+/IgM+, n = 32). Anti- Toxoplasma IgM was never the sole positive test ever (IgG-/IgM+; n = 0). The age of donors ranged from 18 to over 70 years; their mean age was 44.8 years. An equivalent number of sera was analysed in all age groups between 18 and 69, with a mean number of 381 ± 16 sera per age group. The sex ratio (M/F) was around 1 in all age categories (0,95–1,09) (Table 1 ). Blood donors aged 70 and older were fewer than in the younger groups (n = 90). A dramatic increase was observed according to age, from 70 group ( p < 0.001) (Fig. 1 , Table 1 ). Of the 1,015 positive sera, 531 and 484 were obtained from men and women, respectively. Overall, no differences in seroprevalence according to gender were observed (53.3% in males vs 48.7% in females, p = 0.08). However, seroprevalence was more frequently seropositive in men than in women in the age group 30–39 (41.1% versus 27.6% in men and women, respectively, p = 0.03), whereas the prevalence was not statistically different in all other age groups by univariate analysis (Table 1 ). Table 1 Toxoplasma seroprevalence among blood donors by age and gender, France, 2019 (n = 1,995). Age groups years (N) Seroprevalence % Sex Ratio M/F Seroprevalence in males Seroprevalence in females p value a n/N % n/N % 18–29 (N = 396) 18.4 0.95 38/193 19.7 36/203 17.7 0.78 30–39 (N = 384) 34.4 1.00 79/192 41.1 53/192 27.6 0.03 40–49 (N = 395) 53.7 1.01 107/199 53.7 105/196 53.6 0.97 50–59 (N = 371) 68.2 1.03 134/188 71.3 118/183 64.5 0.20 60–69 (N = 359) 74.1 0.99 130/179 72.6 136/180 75.6 0.56 ≥ 70 (N = 90) 87.8 1.09 43/47 91.5 36/43 83.7 0.27 Overall (N = 1,995) 50.8 1.00 531/998 53.2 484/997 48.5 0.08 n: number of positive sera; N: number of tested sera; M: male; F: female a Z test The four patients with low IgG avidity (< 0.200) were aged less than 50 years old, were observed in different age groups (2 in the 18–29, 1 in the 30–39, and 1 in the 40–49 age group). They were observed equally in men and women, and in three distinct French regions, thus were not grouped cases We then compared the seroprevalence for toxoplasmosis according to the place of residence of blood donors. Thirteen to 27 sera (median = 21) were collected in each French department, thus analysis by department was not carried out as sample sizes were too small. The number of sera analysed by French region varied from 38 to 267 (median = 123). The highest prevalences (> 55%) for Toxoplasma gondii were observed in the Northern and South-Western regions of France: Corse (60.5%), Hauts-de-France (56.4%), Nouvelle-Aquitaine (56.3%) and Ile-de-France (55.2%). The lowest prevalences (< 45%) were observed in the Eastern regions of the country: Grand-Est (41.4%), and Auvergne-Rhône-Alpes (44.2%) (Fig. 2 ). Univariate analysis showed that in Grand-Est, seroprevalence was significantly higher in males than in females, in the age group 40 (89.3 vs 56.0% respectively, p = 0.02) (Table 2 ). Overall, in people < 40-year-old, male were more frequently Toxoplasma -seropositive than female in all regions, except Corse and Ile-de-France (Table 2 ). Table 2 Toxoplasma seroprevalence among blood donors by gender, below and over 40 years, and region, France, 2019 (n = 1,995) Regions Males < 40 years (%) Females < 40 years (%) p -value a Males ≥ 40 years (%) Females ≥ 40 years (%) p -value a Auvergne-Rhône-Alpes (N = 258) 30,4 22,9 0,55 48,7 58,0 0,30 Bourgogne-Franche-Comté (N = 177) 37,5 21,2 0,24 64,5 56,0 0,47 Bretagne (N = 83) 27,8 12,5 0,50 64,0 75,0 0,60 Centre-Val de Loire (N = 123) 36,4 22,7 0,51 68,3 63,2 0,81 Corse (N = 38) 28,6 42,9 1,00 81,8 69,2 0,81 Grand Est (N = 227) 25,0 6,3 0,03 54,3 64,6 0,30 Hauts-de-France (N = 94) 22,7 47,4 0,18 89,3 56,0 0,02 Ile-de-France (N = 154) 37,5 20,6 0,21 79,5 70,5 0,46 Normandie (N = 91) 31,6 22,7 0,78 81,5 60,9 0,19 Nouvelle-Aquitaine (N = 252) 27,7 20,8 0,59 74,7 78,2 0,74 Occitanie (N = 267) 28,8 32,1 0,88 74,7 66,3 0,32 Pays de la Loire (N = 108) 40,0 14,3 0,13 66,7 67,6 1,00 Provence-Alpes-Côte d'Azur (N = 123) 20,8 29,2 0,74 63,2 67,6 0,87 a Chi-squared test A multivariable analysis was further performed to confirm the differences of seroprevalences according to sex, age and region. As expected, the risk to be infected by T. gondii increased with age, with an odd ratio rising from 2.278 in the 30–39 age group to 36.135 in the group > 70 ( p < 0.001), compared to the youngest group (Table 3 ). Interestingly, it showed that men were more likely to be infected by T. gondii (OR = 1,234; 95%CI= [1.014;1.503]; p = 0.036) than women. Five regions out of 12 were associated with an at least twice higher risk of being seropositive, compared to the region with the lowest prevalence (Grand-Est), namely Corse (OR = 2.449), Hauts-de-France (OR = 2.453), Île-de-France (OR = 2.17). Table 3 Toxoplasma seroprevalence among blood donors: Multivariate regression analysis by demographic characteristics, France, 2019 (n = 1,995). Variable OR 95% CI p -value Sex Male vs Female 1.234 1.014–1.503 0.036 Age 18–29 Ref. Ref. Ref. 30–39 2.278 1.636–3.171 < 0.001 40–49 5.236 3.789–7.236 < 0.001 50–59 9.447 6.744–13.234 < 0.001 60–69 13.199 9.296–18.741 70 36.135 17.789–73.403 < 0.001 Region Auvergne – Rhône-Alpes 1.090 0.731–1.626 0.672 Bourgogne – Franche-Comté 1.355 0.873–2.105 0.176 Bretagne 1.515 0.862–2.663 0.149 Centre-Val de Loire 1.713 1.046–2.805 0.032 Corse 2.449 1.129–5.313 0.023 Grand-Est Ref. Ref. Ref. Hauts-de-France 2.453 1.421–4.236 0.001 Île-de-France 2.179 1.373–3.460 < 0.001 Normandie 2.039 1.180–3.525 0.011 Nouvelle-Aquitaine 2.030 1.353–3.044 < 0.001 Occitanie 1.922 1.290–2.865 0.001 Pays de la Loire 1.577 0.943–2.636 0.082 Provence-Alpes-Côte d’Azur 1.471 0.900–2.405 0.124 OR: odds ratio; CI: confidence interval DISCUSSION This study is the first one investigating Toxoplasma seroprevalence among a large cohort of French blood donors nationwide. To date, only data from pregnant women are available. The exclusion of blood samples from overseas departments (Réunion, Mayotte, Martinique, Guadeloupe, French Guiana) was decided because of shipping constraints and possible sample alteration. The number of tested sera was the highest ever analysed in this context, which ensures reliable conclusions. Additionally, chance did things well, as the sex ratio of the blood donor population was around 1 for all age categories, which allowed for the first time to compare seroprevalence in male and female. In univariate analysis, a significantly higher prevalence was observed in men aged [30–39] years old ( p < 0.05). This age group corresponds to the average age of 31 years for pregnancies in France, with 95% of first births occurring among mothers aged between 21 and 38 (INSEE data for 2023)[ 11 ]. The policy of prevention and monthly screening for toxoplasmosis implemented in France since 1992 could account for a better awareness of women regarding toxoplasmosis, and might result in more vigilance about food and hygiene to avoid primary toxoplasmosis. This might explain the difference in seroprevalences between men and women aged between 30 and 39. Of note, the mean seroprevalence observed in our study in women of childbearing age (18–39 years) was 22.5% (89/395, Table 1 ), which is very close to the most recent nationwide seroprevalence study of toxoplasmosis in pregnant women (24.9% in mainland France)[ 10 ]. Besides, the mean seroprevalence among blood donors aged > 40 years (66.7%) was similar to that observed among deceased organ donors (68%) in our lab, over a 10-year period (mean age = 61) (data not shown). The high overall seroprevalence of 51% in French blood donors in our study is an important finding, as it shows that the prevalence is still high in the French population which mean age is 42.7 years ( https://www.insee.fr/fr/statistiques/2381476?utm ), which is similar to the mean age of our patient population (44.8). Here, the seroprevalence in subjects aged > 40 years ranged from 54% to 91%. It is well known that seroprevalence increases with age [ 6 , 12 , 13 ], and older age groups are more exposed to the occurrence of various diseases leading to therapeutic immune suppression, a situation where reactivation of chronic toxoplasmosis remains a huge threat [ 14 ]. As already described in the study by Mazzili et al. (2025), the highest seroprevalences in our study were observed in Île-de-France and Southern regions, and the lowest in Eastern region [ 10 ]. These differences in prevalence among regions that are sometimes close to each other can be explained by several factors, firstly by geoclimactic factors. Indeed, it was reported that Toxoplasma seroprevalence was higher in regions with high average temperature (Southern regions), and lower in regions with temperatures falling below − 5°C in winter (Eastern regions), in relation to better survival and sporulation of Toxoplasma oocysts in warmer environments [ 8 ]. Secondly, dietary factors can also account for seroprevalence variation, especially the consumption of sheep meat. Sheep is a mammal with a Toxoplasma prevalence varying among French regions from around 30% (Eastern France) to 72% (South West France)[ 8 ]. A correlation between regions where this meat is commonly eaten, i.e. Southern, Northern and Paris regions, and Toxoplasma prevalence among pregnant women has also been pointed out [ 8 , 15 ]. Berger et al. hypothesized that the supply of sheep meat from countries with low endemicity, such as the United Kingdom and New Zealand, has probably contributed to the decline in the prevalence of toxoplasmosis throughout the years, together with the increasing practise of freezing meat, which destroys Toxoplasma cysts [ 8 ]. Finally, many people originating from overseas territories or African countries where toxoplasmosis is highly prevalent, are living in Île-de-France and Southern regions, thus could contribute to the overall higher seroprevalence observed in these regions. The overall seroprevalence of T. gondii in the present study appears to be higher than those reported among blood donors in other European countries like Portugal (38.1%)[ 16 ] or Scotland (13.2%)[ 12 ] but seems to be similar to those reported in Romania (45.9%)[ 13 ] and Germany (55%)[ 17 ]. In other continents, blood donors were reported with seroprevalence ranging from 5.3% in China [ 18 ], 9.3% in Taiwan [ 19 ], 11.2% in Egypt [ 20 ], 16.8–19.3% in Iran [ 21 , 22 ], 38.5% in Colombia [ 23 ], 42.9% in New Zealand [ 24 ], 44.4% in Tunisia [ 25 ], to 45.3–48% in Brazil [ 26 , 27 ](Table 4 ). These differences could be explained by anthropological factors such as diet or socio-economic status [ 28 ], climate factors and prevalence in wildlife, which is higher in the Amazonian forest [ 29 ]. However, some studies suffer from a poor demographic representativity or a low number of included patients. Indeed, some studies favoured male (Egypt, Iran) or female (New Zealand) recruitment, and others only reported on a small portion of the country population with limited geographical recruitment (China, Brazil, Colombia, Iran, New Zealand) (Table 4 ). Only two studies conducted in Taiwan and Germany were nationwide, as is our study. Noteworthy, our study is particularly robust, as it does not favour one gender over the other (sex ratio = 1) and it displays a representative fraction of the population of each region. Table 4 Comparison of studies on Toxoplasma gondii seroprevalence among blood donors around the world. Country Year Sample size Sex Ratio M/F Location Anti-Toxoplasma IgG prevalence (%) Age (year) Reference France 2024 1,995 1.0 Nationwide France 50.9 18 – >70 Our Study China 2025 702 1.1 Zhejiang Province 5.27 18–59 [ 18 ] Egypt 2024 420 34 Menoufia Province 11.2 17–66 [ 20 ] Brazil 2024 1729 ND São Paulo state 48 ND [ 26 ] 2022 510 1.1 Erechim and Chapeco (Southern Brazil) 45.3 < 29–69 [ 27 ] Romania 2022 1,347 1.3 Western Romania 45.9 18–63 [ 13 ] Tunisia 2020 800 3.9 Gafsa and Monastir 44.4 18–62 [ 25 ] Portugal 2020 520 0.94 Various 38.1 18–65 [ 16 ] Colombia 2019 348 2.45 Cucuta 38.5 18–56 [ 23 ] Scotland 2016 1,403 0.85 Not specified 13.2 17–91 [ 12 ] Germany 2014 6,564 0.91 Nationwide 55 18–79 [ 17 ] Iran 2018 285 30.3 Boyer-Ahmad county 16.8 28–46 [ 22 ] 2014 1,480 16 Fars province 19.3 20–68 [ 21 ] Taiwan 2012 1,783 1.7 Nationwide 9.3 18–65 [ 19 ] New Zealand 2007 140 0.59 Waikato Region 42.9 17–69 [ 24 ] ND: No data The observation of four patients with IgG avidity < 0,200 and positive IgM, raises the question of the risk of parasite transmission through blood transfusion. The presence of high levels of anti- Toxoplasma IgG in all four patients indicates that the primary infection occurred more than a month prior to sampling. Indeed, IgG antibodies are usually detected approximately three weeks after primary infection and increase until they reach a plateau, i.e. two to three months after infection [ 1 ]. More than one month after infection, there are no longer any circulating tachyzoites, and therefore no risk of transmission to a transfused patient [ 1 , 30 ]. We can then assume that none of the patients were at risk of transmitting T. gondii at the time of blood donation. Additionally, it is generally considered that the storage procedure of blood products limits considerably the survival of tachyzoites, which are fragile. Our study has some limitations, as it was conducted over a short period of time (6 months), but it included a high number of samples and was exhaustive over the study period. It would be of interest to perform similar studies in overseas departments or territories (Tahiti, Wallis and Futuna, Saint-Pierre et Miquelon, French Guyana and French West Indies), as geoclimatic conditions and felid densities and diversity are very different from mainland. In conclusion, Toxoplasma seroprevalence in the general population is still high in France, despite a decrease in younger age groups, particularly in women of childbearing age. Declarations Ethics approval Blood donations are made voluntarily to the EFS, and donors give their consent for their use, including serological testing. The study adhered to the Declaration of Helsinki. Samples are anonymized and only a few data remain associated to the sample. Additionally, the study was approved by the ethics committee of the University Hospital of Rennes (approval number #25.153), which waived the necessity to inform patients of the reuse of their blood for secondary study, in relation to the strictly anonymized process and to French regulation (article L . 1211-2 du Code de la Santé Publique). Consent for publication: Not applicable Availability of data and materials: All data analyzed during this study have been shared on Zenodo, on open repository, and can be retrieved as a raw data set using this link : https://doi.org/10.5281/zenodo.18330122 Competing interests: None to disclose Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Authors’ contribution : Conceptualization: JPG, FRG; Investigation: LH; Methodology: FRG; Formal analysis: LH, AB, FRG; Supervision: FRG; Writing original draft: LH; Review & editing: FRG, JPG, AB. All authors read and approved the final manuscript Acknowledgments The authors thank Clémence Pommeron for her kindness and technical support. Use of artificial intelligent tools: None to declare About the author Dr Hamet is a medical biologist, assistant professor in Parasitology at the University Hospital of Rennes, France. Her research interests include the epidemiology of parasitic diseases. References Robert-Gangneux F, Dardé M-L. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25:264–96. Pappas G, Roussos N, Falagas ME. Toxoplasmosis snapshots: global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis. Int J Parasitol. 2009;39:1385–94. Foroutan-Rad M, Majidiani H, Dalvand S, Daryani A, Kooti W, Saki J, et al. Toxoplasmosis in Blood Donors: A Systematic Review and Meta-Analysis. Transfus Med Rev. 2016;30:116–22. Mulu Gelaw Y, Worku Dagnew G, Degu Alene G, Gangneux J-P, Robert-Gangneux F. 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Wilking H, Thamm M, Stark K, Aebischer T, Seeber F. Prevalence, incidence estimations and risk factors of Toxoplasma gondii infection in Germany: a representative, cross-sectional, serological study. Sci Rep. 2016;6:22551. Wang X, Ruan W, Xu W, Chen H, Zhang J, Zhang X, et al. Different patterns of Toxoplasma gondii infection epidemiology in the general population, animal contact workers, and blood donors in southeastern China between 2019 and 2023: a cross-sectional study. Parasite. 2025;32:68. Chiang T-Y, Hsieh H-H, Kuo M-C, Chiu K-T, Lin W-C, Fan C-K, et al. Seroepidemiology of Toxoplasma gondii Infection among Healthy Blood Donors in Taiwan. PLoS ONE. 2012;7:e48139. Gouda MA, Saied SA, Ashry WMO, Abd-Eltwab RA-R, Aldesoky MM, El-Dydamoni OA, et al. Trends of Toxoplasma gondii and common transfusable venereal infections among blood donors in Menoufia Province, Egypt. Sci Rep. 2024;14:20920. Sarkari B, Shafiei R, Zare M, Sohrabpour S, Kasraian L. Seroprevalence and molecular diagnosis of Toxoplasma gondii infection among blood donors in southern Iran. J Infect Dev Ctries. 2014;8:543–7. Moshfe A, Arefkhah N, Sarkari B, Kazemi S, Mardani A. Toxoplasma gondii in Blood Donors: A Study in Boyer-Ahmad County, Southwest Iran. Interdiscip Perspect Infect Dis. 2018;2018:3813612. Ramírez AM, Ríos YK, Galvis NF, Entrena E, Mariño NV, Rangel DM, et al. Seroprevalence and molecular detection of Toxoplasma gondii among donors in a blood bank in Cúcuta, Colombia Introduction: Toxoplasma gondii infection. Biomed Rev Inst Nac Salud. 2019;39:144–56. Zarkovic A, MacMurray C, Deva N, Ghosh S, Whitley D, Guest S. Seropositivity rates for Bartonella henselae, Toxocara canis and Toxoplasma gondii in New Zealand blood donors. Clin Exp Ophthalmol. 2007;35:131–4. Lachkhem A, Lahmar I, Galal L, Babba O, Mezhoud H, Hassine M, et al. Seroprevalence of Toxoplasma gondii among healthy blood donors in two locations in Tunisia and associated risk factors. Parasite Paris Fr. 2020;27:51. Assoni LCP, Nakashima F, de Sousa VP, Paduan NJ, Andreasse IR, Anghinoni TH, et al. Seroepidemiology of Toxoplasma gondii infection in blood donors in a population from the northwestern region of São Paulo state, Brazil. Trans R Soc Trop Med Hyg. 2024;118:102–9. Paraboni MLR, Commodaro AG, Campi-Azevedo AC, Brito-de-Sousa JP, Gonçalves IL, da Costa DF, et al. Seroprevalence and systemic immune biomarkers associated with Toxoplasma gondii infection in blood donors from Southern Brazil. Immunobiology. 2022;227:152294. Bahia-Oliveira LMG, Jones JL, Azevedo-Silva J, Alves CCF, Oréfice F, Addiss DG. Highly endemic, waterborne toxoplasmosis in north Rio de Janeiro state, Brazil. Emerg Infect Dis. 2003;9:55–62. de Thoisy B, Demar M, Aznar C, Carme B. Ecologic correlates of Toxoplasma gondii exposure in free-ranging neotropical mammals. J Wildl Dis. 2003;39:456–9. Guy EC, Joynson DH. Potential of the polymerase chain reaction in the diagnosis of active Toxoplasma infection by detection of parasite in blood. J Infect Dis. 1995;172:319–22. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8896387","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":603880691,"identity":"5cc86570-6a7d-4832-b304-4840564b1139","order_by":0,"name":"Lya Hamet","email":"","orcid":"","institution":"Laboratoire de Parasitologie et Mycologie, Centre Hospitalier Universitaire de Rennes","correspondingAuthor":false,"prefix":"","firstName":"Lya","middleName":"","lastName":"Hamet","suffix":""},{"id":603880692,"identity":"d52161f9-cd24-442e-b6f7-9d4a2dd12054","order_by":1,"name":"Angélique Bonnet","email":"","orcid":"","institution":"Laboratoire de Parasitologie et Mycologie, Centre Hospitalier Universitaire de Rennes","correspondingAuthor":false,"prefix":"","firstName":"Angélique","middleName":"","lastName":"Bonnet","suffix":""},{"id":603880693,"identity":"2d240001-911b-4352-a9c9-8673ce507d22","order_by":2,"name":"Jean-Pierre Gangneux","email":"","orcid":"","institution":"Laboratoire de Parasitologie et Mycologie, Centre Hospitalier Universitaire de Rennes","correspondingAuthor":false,"prefix":"","firstName":"Jean-Pierre","middleName":"","lastName":"Gangneux","suffix":""},{"id":603880694,"identity":"c13a91d2-2867-4937-98ac-640174645644","order_by":3,"name":"Florence Robert-Gangneux","email":"data:image/png;base64,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","orcid":"","institution":"Laboratoire de Parasitologie et Mycologie, Centre Hospitalier Universitaire de Rennes","correspondingAuthor":true,"prefix":"","firstName":"Florence","middleName":"","lastName":"Robert-Gangneux","suffix":""}],"badges":[],"createdAt":"2026-02-16 21:53:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8896387/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8896387/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104582464,"identity":"ded9c60e-03c8-493d-84ed-2758aca3629a","added_by":"auto","created_at":"2026-03-13 15:12:35","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":203537,"visible":true,"origin":"","legend":"\u003cp\u003eAge-dependent \u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence among blood donors per 10-year age group (right axis) and number of sera with IgG+/IgM-, IgG+/IgM+ results and total number analysed per age group (left axis), France, 2019 (n=1,995).\u003c/p\u003e","description":"","filename":"Figure1Toxoplasmaseroprevalence.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8896387/v1/059198c2fccf1a114831154e.jpg"},{"id":104582406,"identity":"05f84b02-5048-49a5-bef0-92b167ddd298","added_by":"auto","created_at":"2026-03-13 15:12:26","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":316595,"visible":true,"origin":"","legend":"\u003cp\u003eToxoplasmosis seroprevalence among blood donors by region of residency, France, 2019 (n=1995). The prevalence (%), and the number of positive sera/total number of analysed sera are shown for each region.\u003c/p\u003e","description":"","filename":"Figure2FrenchMap.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8896387/v1/2711e1087118266324c4a299.jpg"},{"id":104582539,"identity":"2497d4ae-acf3-417b-b6d5-699be6258362","added_by":"auto","created_at":"2026-03-13 15:12:42","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1582835,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8896387/v1/99b413a5-ff8f-4626-904e-72449a6428e2.pdf"},{"id":104582407,"identity":"a119c4af-cea1-4d30-9ef1-f9c7b0565fd9","added_by":"auto","created_at":"2026-03-13 15:12:26","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":72125,"visible":true,"origin":"","legend":"","description":"","filename":"SupTableS1.docx","url":"https://assets-eu.researchsquare.com/files/rs-8896387/v1/fefb3d9c9c663668cf984fc1.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Seroprevalence of toxoplasmosis in France: first study in blood donors","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eToxoplasmosis is a cosmopolitan zoonotic infection caused by an intracellular protozoan, \u003cem\u003eToxoplasma gondii\u003c/em\u003e [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Cats and other felids are the definitive hosts of the parasite while humans, as well as all warm-blooded animals, are intermediate hosts. \u003cem\u003eToxoplasma\u003c/em\u003e is transmitted through the ingestion of water, food or soil, contaminated by oocysts which have been previously spread into the environment by felids faeces. Intermediate hosts then undergo go a systemic dissemination of tachyzoites through the blood stream, resulting in the persistence of encysted parasites in muscles, brain and eyes. As a result, infection can also occur through the ingestion of undercooked meat of intermediate hosts harbouring tissue cysts. Primary infection with \u003cem\u003eToxoplasma gondii\u003c/em\u003e in human is usually benign or asymptomatic in healthy individuals, except when patients are infected with a virulent genotype strain. By contrast, toxoplasmosis is a life-threatening infection in immunocompromised patients, such as HIV-infected patients or transplant patients. It can also be acquired through transplantation to a na\u0026iuml;ve donor of an infected organ containing cysts, or through blood transfusion if it contains tachyzoites [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Vertical transmission to the foetus can happen when toxoplasmosis is acquired during pregnancy, a situation where tachyzoites disseminate through the bloodstream and pass through the placental barrier.\u003c/p\u003e \u003cp\u003eIt is estimated that one third of the population is infected by \u003cem\u003eToxoplasma gondii\u003c/em\u003e, but the seroprevalence varies widely between countries from 10 to 80%, and sometimes within a given country [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Low seroprevalence, below 30%, has been observed in North America and Northern Europe, South East Asia and the Sahelian region of Africa. In Central and Southern Europe prevalence is usually moderate (30\u0026ndash;50%), while high prevalences have been reported in warm and humid areas such as Latin America and tropical African countries [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. In developed countries, contamination seems to be essentially linked to the consumption of infected meat [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In Europe, prevalence varies according to dietary factors, as prevalence is lower in countries where meat is eaten well-cooked (UK, Scandinavia), and higher in France due to the consumption of rare or smoked meat.\u003c/p\u003e \u003cp\u003eSeveral studies have focused on the seroprevalence of \u003cem\u003eT. gondii\u003c/em\u003e among pregnant women [\u003cspan additionalcitationids=\"CR7 CR8 CR9\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], but this specific group is not representative of the French population as a whole. To the best of our knowledge, no seroprevalence studies have focused on French blood donors. Therefore, this study aimed to estimate the prevalence of toxoplasmosis in blood donors, to complete French epidemiological data.\u003c/p\u003e"},{"header":"MATERIAL AND METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSample collection\u003c/h2\u003e \u003cp\u003eThis is a retrospective study conducted at Rennes University Hospital (Rennes, France), aiming at assessing the seroprevalence of toxoplasmosis in French metropolitan blood donors. Sera were obtained through donation by the blood French establishment (Etablissement Fran\u0026ccedil;ais du Sang, EFS) before destruction. Sera were collected from adult patients during blood donation and stored for usual serologic screening to secure blood-derived products. The donation to Rennes University Hospital consisted of all sera collected in all French regions, overseas territories excluded, between July 1st and December 31st 2019.\u003c/p\u003e \u003cp\u003eFor each serum, available information was: sex, age range by decade (as the date of birth was not precisely known), and department/region of France where blood donation took place.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSerological tests\u003c/h3\u003e\n\u003cp\u003eAll sera were included in the study and tested for anti-\u003cem\u003eToxoplasma\u003c/em\u003e IgG and IgM antibodies using the Platelia\u0026reg; Toxo IgG and Platelia\u0026reg; Toxo IgM (Bio-Rad, Marnes-la-Coquette, France). In case of doubtful results for IgG (IgG titer in the range 6\u0026ndash;8 IU/mL) and/or doubtful or positive IgM (IgM index in the range 0.8-0.999) using these kits, a confirmation technique was performed, using the VIDAS\u0026reg; Toxo IgG II and VIDAS\u0026reg; Toxo IgM (BioM\u0026eacute;rieux, Marcy-l\u0026rsquo;Etoile, France), respectively. When IgG remained doubtful with both previous techniques, a western blot (WB) was performed using the Toxo II IgG confirmation kit (LD Bio Diagnostics, Lyon, France), and interpreted according to the manufacturer\u0026rsquo;s recommendations. All IgM-positive sera with simultaneous IgG detection benefited from an IgG avidity assay using the VIDAS\u0026reg; Toxo IgG Avidity kit (BioM\u0026eacute;rieux). A high avidity\u0026thinsp;\u0026ge;\u0026thinsp;0.300 can exclude primary infection within the last 4 previous months, while low avidity\u0026thinsp;\u0026lt;\u0026thinsp;0.200 may suggest recent infection with \u003cem\u003eT. gondii\u003c/em\u003e. An intermediate avidity between 0.200 and 0.299 is inconclusive.\u003c/p\u003e \u003cp\u003e \u003cem\u003eToxoplasma\u003c/em\u003e infection was defined by the presence of specific anti-\u003cem\u003eToxoplasma\u003c/em\u003e IgG with or without specific IgM.\u003c/p\u003e\n\u003ch3\u003eStatistics\u003c/h3\u003e\n\u003cp\u003eThe mean age of the study population was calculated by multiplying the number of patients by the midpoint value of each age category, divided by the total number of patients. Prevalences were compared across categories (age class, sex, region of residency) using a Chi-squared test, or a Z test (age class, sex). Statistics were made using GraphPad Prims v10.1 software.\u003c/p\u003e \u003cp\u003eA multivariable logistic regression model was then performed to estimate adjusted odds ratios (ORs) and their 95% confidence intervals (95% CI). The reference categories were 18\u0026ndash;29-year-old, female, and Grand-Est, for age, sex and region, respectively. Statistical significance was assessed using a two-sided threshold of \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Model fit was evaluated using the likelihood ratio test and McFadden\u0026rsquo;s pseudo-R\u0026sup2;. Multivariable analysis was performed using Python, with pandas library for data management and statsmodels for statistical modelling.\u003c/p\u003e\n\u003ch3\u003eEthics approval\u003c/h3\u003e\n\u003cp\u003e Blood donations are made voluntarily to the EFS, and donors give their consent for their use, including serological testing. The study adhered to the Declaration of Helsinki. Samples are anonymized and only a few data remain associated to the sample. Additionally, the study was approved by the ethics committee of the University Hospital of Rennes (approval number #25.153), which waived the necessity to inform patients of the reuse of their blood for secondary study, in relation to the strictly anonymized process and to French regulation (article L. 1211-2 du Code de la Sant\u0026eacute; Publique).\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eIn total, 1,995 sera were collected from healthy blood donors from the 12 regions of France. Platelia\u0026reg; Toxo IgG were positive and doubtful in 1,010 and 8 cases, respectively, while Platelia\u0026reg; Toxo IgM were doubtful or positive in 173 sera (8,7%), thus needed to be confirmed by VIDAS\u0026reg; Toxo IgG or VIDAS\u0026reg; Toxo IgM. Thirty-two IgM and 5 IgG results were confirmed positive or doubtful with VIDAS\u0026reg; (sup. \u003cb\u003eTable \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e\u003c/b\u003e). Three sera with doubtful IgG results with both techniques were confirmed positive using the WB. An IgG avidity test was performed on all sera with positive IgG associated with positive or doubtful IgM (n\u0026thinsp;=\u0026thinsp;32), of which 26 (81%) had high IgG avidity (infection dating more than 4 months ago), 4 had low IgG avidity and 2 were in the grey zone, thus recent infection could not be excluded.\u003c/p\u003e \u003cp\u003eOverall, of the 1,995 blood donors, 51% (n\u0026thinsp;=\u0026thinsp;1,015) had IgG antibodies against \u003cem\u003eToxoplasma gondii\u003c/em\u003e (IgG+/IgM-, n\u0026thinsp;=\u0026thinsp;983; IgG+/IgM+, n\u0026thinsp;=\u0026thinsp;32). Anti-\u003cem\u003eToxoplasma\u003c/em\u003e IgM was never the sole positive test ever (IgG-/IgM+; n\u0026thinsp;=\u0026thinsp;0).\u003c/p\u003e \u003cp\u003eThe age of donors ranged from 18 to over 70 years; their mean age was 44.8 years. An equivalent number of sera was analysed in all age groups between 18 and 69, with a mean number of 381\u0026thinsp;\u0026plusmn;\u0026thinsp;16 sera per age group. The sex ratio (M/F) was around 1 in all age categories (0,95\u0026ndash;1,09) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Blood donors aged 70 and older were fewer than in the younger groups (n\u0026thinsp;=\u0026thinsp;90). A dramatic increase was observed according to age, from \u0026lt;\u0026thinsp;20% in the 18\u0026ndash;29 age group to almost 90% in the \u0026gt;\u0026thinsp;70 group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Of the 1,015 positive sera, 531 and 484 were obtained from men and women, respectively. Overall, no differences in seroprevalence according to gender were observed (53.3% in males vs 48.7% in females, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.08). However, seroprevalence was more frequently seropositive in men than in women in the age group 30\u0026ndash;39 (41.1% versus 27.6% in men and women, respectively, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.03), whereas the prevalence was not statistically different in all other age groups by univariate analysis (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e\u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence among blood donors by age and gender, France, 2019 (n\u0026thinsp;=\u0026thinsp;1,995).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge groups years\u003c/p\u003e \u003cp\u003e(N)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSeroprevalence\u003c/p\u003e \u003cp\u003e%\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSex Ratio M/F\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eSeroprevalence in males\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eSeroprevalence in females\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003en/N\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003en/N\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e18\u0026ndash;29\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;396)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e18.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.95\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e38/193\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e19.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e36/203\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e17.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.78\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e30\u0026ndash;39\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;384)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e34.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e79/192\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e41.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e53/192\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e27.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u003cb\u003e0.03\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e40\u0026ndash;49\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;395)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e53.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e107/199\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e53.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e105/196\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e53.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e50\u0026ndash;59\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;371)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e68.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e134/188\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e71.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e118/183\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e64.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e60\u0026ndash;69\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;359)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e74.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e130/179\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e72.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e136/180\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e75.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e\u0026ge;\u0026thinsp;70\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;90)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e87.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e43/47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e91.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e36/43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e83.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.27\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOverall\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(N\u0026thinsp;=\u0026thinsp;1,995)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e50.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e531/998\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e53.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e484/997\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e48.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003en: number of positive sera; N: number of tested sera; M: male; F: female\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003e\u003csup\u003ea\u003c/sup\u003eZ test\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe four patients with low IgG avidity (\u0026lt;\u0026thinsp;0.200) were aged less than 50 years old, were observed in different age groups (2 in the 18\u0026ndash;29, 1 in the 30\u0026ndash;39, and 1 in the 40\u0026ndash;49 age group). They were observed equally in men and women, and in three distinct French regions, thus were not grouped cases\u003c/p\u003e \u003cp\u003eWe then compared the seroprevalence for toxoplasmosis according to the place of residence of blood donors. Thirteen to 27 sera (median\u0026thinsp;=\u0026thinsp;21) were collected in each French department, thus analysis by department was not carried out as sample sizes were too small. The number of sera analysed by French region varied from 38 to 267 (median\u0026thinsp;=\u0026thinsp;123). The highest prevalences (\u0026gt;\u0026thinsp;55%) for \u003cem\u003eToxoplasma gondii\u003c/em\u003e were observed in the Northern and South-Western regions of France: Corse (60.5%), Hauts-de-France (56.4%), Nouvelle-Aquitaine (56.3%) and Ile-de-France (55.2%). The lowest prevalences (\u0026lt;\u0026thinsp;45%) were observed in the Eastern regions of the country: Grand-Est (41.4%), and Auvergne-Rh\u0026ocirc;ne-Alpes (44.2%) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Univariate analysis showed that in Grand-Est, seroprevalence was significantly higher in males than in females, in the age group\u0026thinsp;\u0026lt;\u0026thinsp;40 years (25.0 \u003cem\u003evs\u003c/em\u003e 6.3% respectively, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.03), while in Hauts-de-France, it was higher in males than in females aged\u0026thinsp;\u0026gt;\u0026thinsp;40 (89.3 \u003cem\u003evs\u003c/em\u003e 56.0% respectively, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Overall, in people\u0026thinsp;\u0026lt;\u0026thinsp;40-year-old, male were more frequently \u003cem\u003eToxoplasma\u003c/em\u003e-seropositive than female in all regions, except Corse and Ile-de-France (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e\u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence among blood donors by gender, below and over 40 years, and region, France, 2019 (n\u0026thinsp;=\u0026thinsp;1,995)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRegions\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMales\u0026thinsp;\u0026lt;\u0026thinsp;40 years\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFemales\u0026thinsp;\u0026lt;\u0026thinsp;40 years\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMales\u0026thinsp;\u0026ge;\u0026thinsp;40 years\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eFemales\u0026thinsp;\u0026ge;\u0026thinsp;40 years\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAuvergne-Rh\u0026ocirc;ne-Alpes (N\u0026thinsp;=\u0026thinsp;258)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e30,4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e48,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e58,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBourgogne-Franche-Comt\u0026eacute; (N\u0026thinsp;=\u0026thinsp;177)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e64,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e56,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBretagne (N\u0026thinsp;=\u0026thinsp;83)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e27,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e12,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e64,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e75,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,60\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCentre-Val de Loire (N\u0026thinsp;=\u0026thinsp;123)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e36,4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e68,3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e63,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,81\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCorse (N\u0026thinsp;=\u0026thinsp;38)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e28,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e42,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1,00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e81,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e69,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,81\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGrand Est (N\u0026thinsp;=\u0026thinsp;227)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e25,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6,3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0,03\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e54,3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e64,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHauts-de-France (N\u0026thinsp;=\u0026thinsp;94)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e22,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e47,4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e89,3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e56,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0,02\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eIle-de-France (N\u0026thinsp;=\u0026thinsp;154)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e20,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e79,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e70,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,46\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eNormandie (N\u0026thinsp;=\u0026thinsp;91)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e31,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e81,5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e60,9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,19\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eNouvelle-Aquitaine (N\u0026thinsp;=\u0026thinsp;252)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e27,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e20,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e74,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e78,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,74\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOccitanie (N\u0026thinsp;=\u0026thinsp;267)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e28,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e32,1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e74,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e66,3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,32\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePays de la Loire (N\u0026thinsp;=\u0026thinsp;108)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e40,0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14,3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e66,7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e67,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e1,00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eProvence-Alpes-C\u0026ocirc;te d'Azur (N\u0026thinsp;=\u0026thinsp;123)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e20,8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e29,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0,74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e63,2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e67,6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0,87\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e\u003csup\u003ea\u003c/sup\u003eChi-squared test\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eA multivariable analysis was further performed to confirm the differences of seroprevalences according to sex, age and region. As expected, the risk to be infected by \u003cem\u003eT. gondii\u003c/em\u003e increased with age, with an odd ratio rising from 2.278 in the 30\u0026ndash;39 age group to 36.135 in the group\u0026thinsp;\u0026gt;\u0026thinsp;70 (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001), compared to the youngest group (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Interestingly, it showed that men were more likely to be infected by \u003cem\u003eT. gondii\u003c/em\u003e (OR\u0026thinsp;=\u0026thinsp;1,234; 95%CI= [1.014;1.503]; \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.036) than women. Five regions out of 12 were associated with an at least twice higher risk of being seropositive, compared to the region with the lowest prevalence (Grand-Est), namely Corse (OR\u0026thinsp;=\u0026thinsp;2.449), Hauts-de-France (OR\u0026thinsp;=\u0026thinsp;2.453), \u0026Icirc;le-de-France (OR\u0026thinsp;=\u0026thinsp;2.17).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003e\u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence among blood donors: Multivariate regression analysis by demographic characteristics, France, 2019 (n\u0026thinsp;=\u0026thinsp;1,995).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSex\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale \u003cem\u003evs\u003c/em\u003e Female\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.234\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.014\u0026ndash;1.503\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.036\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18\u0026ndash;29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u0026ndash;39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.278\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.636\u0026ndash;3.171\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40\u0026ndash;49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e5.236\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.789\u0026ndash;7.236\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50\u0026ndash;59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e9.447\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.744\u0026ndash;13.234\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e60\u0026ndash;69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e13.199\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.296\u0026ndash;18.741\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e36.135\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.789\u0026ndash;73.403\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRegion\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAuvergne \u0026ndash; Rh\u0026ocirc;ne-Alpes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.090\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.731\u0026ndash;1.626\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.672\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBourgogne \u0026ndash; Franche-Comt\u0026eacute;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.355\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.873\u0026ndash;2.105\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.176\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBretagne\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.515\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.862\u0026ndash;2.663\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.149\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCentre-Val de Loire\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.713\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.046\u0026ndash;2.805\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.032\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCorse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.449\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.129\u0026ndash;5.313\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.023\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGrand-Est\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eRef.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHauts-de-France\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.453\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.421\u0026ndash;4.236\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026Icirc;le-de-France\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.179\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.373\u0026ndash;3.460\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormandie\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.039\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.180\u0026ndash;3.525\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNouvelle-Aquitaine\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e2.030\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.353\u0026ndash;3.044\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOccitanie\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1.922\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.290\u0026ndash;2.865\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePays de la Loire\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.577\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.943\u0026ndash;2.636\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.082\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eProvence-Alpes-C\u0026ocirc;te d\u0026rsquo;Azur\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.471\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.900\u0026ndash;2.405\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.124\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eOR: odds ratio; CI: confidence interval\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThis study is the first one investigating \u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence among a large cohort of French blood donors nationwide. To date, only data from pregnant women are available. The exclusion of blood samples from overseas departments (R\u0026eacute;union, Mayotte, Martinique, Guadeloupe, French Guiana) was decided because of shipping constraints and possible sample alteration. The number of tested sera was the highest ever analysed in this context, which ensures reliable conclusions. Additionally, chance did things well, as the sex ratio of the blood donor population was around 1 for all age categories, which allowed for the first time to compare seroprevalence in male and female. In univariate analysis, a significantly higher prevalence was observed in men aged [30\u0026ndash;39] years old (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). This age group corresponds to the average age of 31 years for pregnancies in France, with 95% of first births occurring among mothers aged between 21 and 38 (INSEE data for 2023)[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. The policy of prevention and monthly screening for toxoplasmosis implemented in France since 1992 could account for a better awareness of women regarding toxoplasmosis, and might result in more vigilance about food and hygiene to avoid primary toxoplasmosis. This might explain the difference in seroprevalences between men and women aged between 30 and 39. Of note, the mean seroprevalence observed in our study in women of childbearing age (18\u0026ndash;39 years) was 22.5% (89/395, Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), which is very close to the most recent nationwide seroprevalence study of toxoplasmosis in pregnant women (24.9% in mainland France)[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Besides, the mean seroprevalence among blood donors aged\u0026thinsp;\u0026gt;\u0026thinsp;40 years (66.7%) was similar to that observed among deceased organ donors (68%) in our lab, over a 10-year period (mean age\u0026thinsp;=\u0026thinsp;61) (data not shown).\u003c/p\u003e \u003cp\u003eThe high overall seroprevalence of 51% in French blood donors in our study is an important finding, as it shows that the prevalence is still high in the French population which mean age is 42.7 years (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.insee.fr/fr/statistiques/2381476?utm\u003c/span\u003e\u003cspan address=\"https://www.insee.fr/fr/statistiques/2381476?utm\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), which is similar to the mean age of our patient population (44.8). Here, the seroprevalence in subjects aged\u0026thinsp;\u0026gt;\u0026thinsp;40 years ranged from 54% to 91%. It is well known that seroprevalence increases with age [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], and older age groups are more exposed to the occurrence of various diseases leading to therapeutic immune suppression, a situation where reactivation of chronic toxoplasmosis remains a huge threat [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAs already described in the study by Mazzili \u003cem\u003eet al.\u003c/em\u003e (2025), the highest seroprevalences in our study were observed in \u0026Icirc;le-de-France and Southern regions, and the lowest in Eastern region [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. These differences in prevalence among regions that are sometimes close to each other can be explained by several factors, firstly by geoclimactic factors. Indeed, it was reported that \u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence was higher in regions with high average temperature (Southern regions), and lower in regions with temperatures falling below \u0026minus;\u0026thinsp;5\u0026deg;C in winter (Eastern regions), in relation to better survival and sporulation of \u003cem\u003eToxoplasma\u003c/em\u003e oocysts in warmer environments [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Secondly, dietary factors can also account for seroprevalence variation, especially the consumption of sheep meat. Sheep is a mammal with a \u003cem\u003eToxoplasma\u003c/em\u003e prevalence varying among French regions from around 30% (Eastern France) to 72% (South West France)[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. A correlation between regions where this meat is commonly eaten, i.e. Southern, Northern and Paris regions, and \u003cem\u003eToxoplasma\u003c/em\u003e prevalence among pregnant women has also been pointed out [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Berger \u003cem\u003eet al.\u003c/em\u003e hypothesized that the supply of sheep meat from countries with low endemicity, such as the United Kingdom and New Zealand, has probably contributed to the decline in the prevalence of toxoplasmosis throughout the years, together with the increasing practise of freezing meat, which destroys \u003cem\u003eToxoplasma\u003c/em\u003e cysts [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Finally, many people originating from overseas territories or African countries where toxoplasmosis is highly prevalent, are living in \u0026Icirc;le-de-France and Southern regions, thus could contribute to the overall higher seroprevalence observed in these regions.\u003c/p\u003e \u003cp\u003eThe overall seroprevalence of \u003cem\u003eT. gondii\u003c/em\u003e in the present study appears to be higher than those reported among blood donors in other European countries like Portugal (38.1%)[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] or Scotland (13.2%)[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] but seems to be similar to those reported in Romania (45.9%)[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] and Germany (55%)[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In other continents, blood donors were reported with seroprevalence ranging from 5.3% in China [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], 9.3% in Taiwan [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], 11.2% in Egypt [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], 16.8\u0026ndash;19.3% in Iran [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], 38.5% in Colombia [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], 42.9% in New Zealand [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e], 44.4% in Tunisia [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], to 45.3\u0026ndash;48% in Brazil [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e](Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). These differences could be explained by anthropological factors such as diet or socio-economic status [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], climate factors and prevalence in wildlife, which is higher in the Amazonian forest [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. However, some studies suffer from a poor demographic representativity or a low number of included patients. Indeed, some studies favoured male (Egypt, Iran) or female (New Zealand) recruitment, and others only reported on a small portion of the country population with limited geographical recruitment (China, Brazil, Colombia, Iran, New Zealand) (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Only two studies conducted in Taiwan and Germany were nationwide, as is our study. Noteworthy, our study is particularly robust, as it does not favour one gender over the other (sex ratio\u0026thinsp;=\u0026thinsp;1) and it displays a representative fraction of the population of each region.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison of studies on \u003cem\u003eToxoplasma gondii\u003c/em\u003e seroprevalence among blood donors around the world.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCountry\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYear\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSample size\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSex Ratio M/F\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLocation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAnti-Toxoplasma\u003c/p\u003e \u003cp\u003eIgG prevalence (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eAge (year)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2024\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,995\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNationwide France\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e50.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18 \u0026ndash; \u0026gt;70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eOur Study\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2025\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e702\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eZhejiang Province\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u0026ndash;59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEgypt\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2024\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e420\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMenoufia Province\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e11.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e17\u0026ndash;66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eBrazil\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2024\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1729\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eND\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eS\u0026atilde;o Paulo state\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eND\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2022\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e510\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eErechim and Chapeco (Southern Brazil)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e45.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;29\u0026ndash;69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRomania\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2022\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,347\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eWestern Romania\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e45.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u0026ndash;63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTunisia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e800\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGafsa and Monastir\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e44.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u0026ndash;62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePortugal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e520\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVarious\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e38.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u0026ndash;65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eColombia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2019\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e348\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eCucuta\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e38.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u0026ndash;56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eScotland\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2016\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,403\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNot specified\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e17\u0026ndash;91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGermany\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6,564\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eNationwide\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u0026ndash;79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eIran\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2018\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e285\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eBoyer-Ahmad county\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e16.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e28\u0026ndash;46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2014\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1,480\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFars province\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e19.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e20\u0026ndash;68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e 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\u003c/p\u003e \u003cp\u003eThe observation of four patients with IgG avidity\u0026thinsp;\u0026lt;\u0026thinsp;0,200 and positive IgM, raises the question of the risk of parasite transmission through blood transfusion. The presence of high levels of anti-\u003cem\u003eToxoplasma\u003c/em\u003e IgG in all four patients indicates that the primary infection occurred more than a month prior to sampling. Indeed, IgG antibodies are usually detected approximately three weeks after primary infection and increase until they reach a plateau, i.e. two to three months after infection [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. More than one month after infection, there are no longer any circulating tachyzoites, and therefore no risk of transmission to a transfused patient [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. We can then assume that none of the patients were at risk of transmitting \u003cem\u003eT. gondii\u003c/em\u003e at the time of blood donation. Additionally, it is generally considered that the storage procedure of blood products limits considerably the survival of tachyzoites, which are fragile.\u003c/p\u003e \u003cp\u003eOur study has some limitations, as it was conducted over a short period of time (6 months), but it included a high number of samples and was exhaustive over the study period. It would be of interest to perform similar studies in overseas departments or territories (Tahiti, Wallis and Futuna, Saint-Pierre et Miquelon, French Guyana and French West Indies), as geoclimatic conditions and felid densities and diversity are very different from mainland.\u003c/p\u003e \u003cp\u003eIn conclusion, \u003cem\u003eToxoplasma\u003c/em\u003e seroprevalence in the general population is still high in France, despite a decrease in younger age groups, particularly in women of childbearing age.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBlood donations are made voluntarily to the EFS, and donors give their consent for their use, including serological testing. The study adhered to the Declaration of Helsinki. Samples are anonymized and only a few data remain associated to the sample. Additionally, the study was approved by the ethics committee of the University Hospital of Rennes (approval number #25.153), which waived the necessity to inform patients of the reuse of their blood for secondary study, in relation to the strictly anonymized process and to French regulation (article L\u0026nbsp;. 1211-2 du Code de la Sant\u0026eacute; Publique).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data analyzed during this study have been shared on Zenodo, on open repository, and can be retrieved as a raw data set using this link : https://doi.org/10.5281/zenodo.18330122\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eNone to disclose\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contribution\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eConceptualization: JPG, FRG; Investigation: LH; Methodology: FRG; Formal analysis: LH, AB, FRG; \u0026nbsp;Supervision: FRG; \u0026nbsp;Writing original draft: LH; Review \u0026amp; editing: FRG, JPG, AB.\u003c/p\u003e\n\u003cp\u003eAll authors read and approved the final manuscript\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank Cl\u0026eacute;mence Pommeron for her kindness and technical support.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUse of artificial intelligent tools:\u003c/strong\u003e None to declare\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAbout the author\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDr Hamet is a medical biologist, assistant professor in Parasitology at the University Hospital of Rennes, France. Her research interests include the epidemiology of parasitic diseases.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eRobert-Gangneux F, Dard\u0026eacute; M-L. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25:264\u0026ndash;96.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePappas G, Roussos N, Falagas ME. Toxoplasmosis snapshots: global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis. Int J Parasitol. 2009;39:1385\u0026ndash;94.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eForoutan-Rad M, Majidiani H, Dalvand S, Daryani A, Kooti W, Saki J, et al. Toxoplasmosis in Blood Donors: A Systematic Review and Meta-Analysis. Transfus Med Rev. 2016;30:116\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMulu Gelaw Y, Worku Dagnew G, Degu Alene G, Gangneux J-P, Robert-Gangneux F. 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Biomed Rev Inst Nac Salud. 2019;39:144\u0026ndash;56.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZarkovic A, MacMurray C, Deva N, Ghosh S, Whitley D, Guest S. Seropositivity rates for Bartonella henselae, Toxocara canis and Toxoplasma gondii in New Zealand blood donors. Clin Exp Ophthalmol. 2007;35:131\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLachkhem A, Lahmar I, Galal L, Babba O, Mezhoud H, Hassine M, et al. Seroprevalence of Toxoplasma gondii among healthy blood donors in two locations in Tunisia and associated risk factors. Parasite Paris Fr. 2020;27:51.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAssoni LCP, Nakashima F, de Sousa VP, Paduan NJ, Andreasse IR, Anghinoni TH, et al. Seroepidemiology of Toxoplasma gondii infection in blood donors in a population from the northwestern region of S\u0026atilde;o Paulo state, Brazil. Trans R Soc Trop Med Hyg. 2024;118:102\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParaboni MLR, Commodaro AG, Campi-Azevedo AC, Brito-de-Sousa JP, Gon\u0026ccedil;alves IL, da Costa DF, et al. Seroprevalence and systemic immune biomarkers associated with Toxoplasma gondii infection in blood donors from Southern Brazil. Immunobiology. 2022;227:152294.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBahia-Oliveira LMG, Jones JL, Azevedo-Silva J, Alves CCF, Or\u0026eacute;fice F, Addiss DG. Highly endemic, waterborne toxoplasmosis in north Rio de Janeiro state, Brazil. Emerg Infect Dis. 2003;9:55\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ede Thoisy B, Demar M, Aznar C, Carme B. Ecologic correlates of Toxoplasma gondii exposure in free-ranging neotropical mammals. J Wildl Dis. 2003;39:456\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuy EC, Joynson DH. Potential of the polymerase chain reaction in the diagnosis of active Toxoplasma infection by detection of parasite in blood. J Infect Dis. 1995;172:319\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-epidemiology-and-global-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Journal of Epidemiology and Global Health](https://www.springer.com/journal/44197)","snPcode":"44197","submissionUrl":"https://submission.nature.com/new-submission/44197/3","title":"Journal of Epidemiology and Global Health","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Toxoplasmosis, Toxoplasma gondii, serology, seroprevalence, blood donors","lastPublishedDoi":"10.21203/rs.3.rs-8896387/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8896387/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe seroprevalence of toxoplasmosis is well-described in French pregnant women, but no data are available in the general population. This study investigated 1,995 blood donors (sex ratio\u0026thinsp;=\u0026thinsp;1), aged 18 to \u0026gt;\u0026thinsp;70 years (mean 44.8). The seroprevalence was 51% and increased with age, reaching almost 90% in patients\u0026thinsp;\u0026gt;\u0026thinsp;70. Men exhibited a higher seroprevalence than women in age group 30\u0026ndash;39 (41.1% \u003cem\u003evs\u003c/em\u003e 27.6%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Multivariate analysis confirmed that men were more likely to be infected than women (OR\u0026thinsp;=\u0026thinsp;1.234, p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The highest prevalences for \u003cem\u003eToxoplasma\u003c/em\u003e were observed in the Northern and South-Western regions of France (55.2 to 60.5%). The lowest prevalence was observed in the East (41.4%), and was significantly higher in men\u0026thinsp;\u0026lt;\u0026thinsp;40 years. These data are consistent with prevalence studies conducted in French pregnant women, but shows for the first time that females are less frequently infected than male, particularly in some regions, which could motivate further epidemiological investigations.\u003c/p\u003e","manuscriptTitle":"Seroprevalence of toxoplasmosis in France: first study in blood donors","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-13 15:11:49","doi":"10.21203/rs.3.rs-8896387/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-26T17:37:39+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-26T17:17:09+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-26T16:14:11+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-24T12:51:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"192006309687292079726818712515935016352","date":"2026-03-18T20:20:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"61807760119054801558713002810579407874","date":"2026-03-16T06:53:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"327343015246759901522596953224050686209","date":"2026-03-12T07:54:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"217083502487784808304384257768376649731","date":"2026-03-10T14:25:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"157088342067753968321235181060983455252","date":"2026-03-10T07:45:54+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"117335852790225318343154201496015139554","date":"2026-03-09T21:19:44+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-09T21:12:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-06T08:04:01+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-04T23:05:26+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Epidemiology and Global Health","date":"2026-03-04T15:49:30+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-epidemiology-and-global-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Journal of Epidemiology and Global Health](https://www.springer.com/journal/44197)","snPcode":"44197","submissionUrl":"https://submission.nature.com/new-submission/44197/3","title":"Journal of Epidemiology and Global Health","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f124ab98-0a84-45b0-8f40-0cee9d8da777","owner":[],"postedDate":"March 13th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-17T11:26:08+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-13 15:11:49","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8896387","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8896387","identity":"rs-8896387","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}