Human Bocavirus as a Contributor to Respiratory Disease in Lagos, Nigeria: A Hospital-Based Study

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ANJORIN, Oluwaseyi S. ASHAKA, Joseph EYEDO, Abdulrauf O. ABDULKAREEM, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5997893/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Human Bocavirus (HBoV) is a single-stranded DNA virus from the Parvoviridae family that is associated with respiratory and gastrointestinal infections. The prevalence and impact of the HBoV in Lagos, Nigeria, particularly across all age groups, remain underexplored. Aim This study aimed to determine the prevalence of HBoV among individuals with respiratory symptoms in Lagos, Nigeria, and its association with respiratory disease. Methods A hospital-based, cross-sectional study was conducted from December 2022 to May 2023 in Lagos. Nasopharyngeal swabs were collected from 400 participants presenting with respiratory symptoms across diverse age groups. The samples were analysed for HBoV DNA using real-time PCR. Demographic and clinical data were recorded, and statistical analysis was performed using SPSS. Results The overall prevalence of HBoV was 12.5% (57/400), with a higher prevalence in participants aged 21–30 years (24.6%) than in those aged ≤ 10 years (8.4%). The participants diagnosed with respiratory disease had a significantly greater prevalence of HBoV (20.3%) compared to those without respiratory disease (8.4%) (χ²=11.69, p = 0.0006). Fever and runny nose were the most common symptoms among HBoV-positive participants, regardless of respiratory disease status. Conclusions HBoV is prevalent in Lagos and contributes significantly to respiratory illnesses across all age groups, with the highest burden observed in young adults. These findings underscore the need for further research on the clinical implications of HBoV and its potential for nosocomial transmission in healthcare settings. Trial registration: Not applicable. Human Bocavirus (HBoV) Respiratory disease Prevalence Molecular detection Nigeria Figures Figure 1 Figure 2 Introduction Globally, zoonotic diseases are responsible for an estimated one billion cases of illness and millions of fatalities annually. Scientific evidence suggests that three out of every four emerging infectious diseases are zoonotic in origin, with over half of these infections transmitted from animals to humans [ 1 , 2 ]. Bocavirus, a virus with zoonotic origins, derives its name from the canine minute virus and bovine parvovirus, highlighting its evolutionary lineage [ 3 , 4 ]. Human Bocavirus (HBoV), a member of the Parvoviridae family and Parvovirinae subfamily, is a single-stranded DNA virus that is consistent with other viruses in this family. HBoV primarily causes acute respiratory tract infections across all age groups, with severe infections more commonly reported at the extremes of age [ 5 – 7 ]. The virus was first isolated from a nasopharyngeal specimen from an infant with respiratory disease and has since garnered significant attention [ 5 ]. Globally, the prevalence of HBoV is estimated at approximately 6%, with reports of infections resulting in fatalities [ 7 – 10 ]. HBoV comprises four genotypes, each distinguishable by its route of infection. While HBoV-1 is associated primarily with respiratory infections, HBoV-2 to HBoV-4 are more frequently linked to gastrointestinal infections. The evidence indicates that HBoV may persist in the respiratory tract post-infection, with low-level viremia detectable for months. However, the clinical significance of HBoV is often questioned because of its frequent co-detection with other respiratory viruses [ 11 – 13 ]. The role of HBoV in gastrointestinal infections has also been investigated, with viral detection in stool samples suggesting a possible fecal-oral transmission route [ 14 , 15 ]. However, its exact contribution to gastroenteritis remains undefined. The detection of HBoV in both symptomatic and asymptomatic individuals further complicates its association with specific diseases [ 14 , 16 , 17 ]. Notably, HBoV has been detected in diverse samples, including blood, cerebrospinal fluid, urine, saliva, tonsils, and even environmental samples. This wide detection spectrum may reflect viral persistence post-exposure, akin to its Parvovirus B19 relative, although definitive conclusions remain elusive [ 18 ]. Studies on HBoV prevalence and genetic diversity have been conducted globally, yielding various results. In Nigeria, a prevalence of 2.4% was reported among children with acute respiratory infections in Oyo State, with coinfections involving other respiratory viruses being common [ 19 ]. Another Nigerian study reported an 8.1% prevalence of HBoV-1 in children with respiratory tract infections [ 20 ]. Internationally, Arnott et al. [ 21 ] reported a 1.5% prevalence in Cambodian patients with pneumonia, whereas Alkhalf et al. [ 22 ] reported a 1.6% prevalence among children with respiratory symptoms in Saudi Arabia. Despite these findings, there is limited information on the prevalence of HBoV in Lagos, a cosmopolitan hub in Nigeria. Previous studies in Nigeria have focused predominantly on pediatric populations, leaving a significant gap in understanding the prevalence of HBoV across all age groups. This study therefore assessed the prevalence of HBoV across diverse age strata in individuals presenting with respiratory infections in Lagos, Nigeria. This study provides insights into the contribution of HBoV to respiratory illnesses among hospital attendees, addressing a critical gap in the epidemiological understanding of this virus in the region. Participants and Methods Study Design and Population This was a hospital-based, cross-sectional prospective study conducted between December 2022 and May 2023. The study included participants of all age groups who visited selected healthcare facilities in Lagos, Nigeria, for respiratory illnesses. Three primary healthcare centers- Agbede Primary Health Center (Ikorodu), Iba Primary Health Center (Ojo), and Lagos State University Health Center- were purposively selected to represent diverse patient demographics, including those of children and adults. Additionally, Lagos State University Teaching Hospital, the only tertiary healthcare facility in the area, was included to capture urban populations and cases requiring advanced care. Participants were consecutively recruited during routine medical visits. Demographic and clinical data, including age, sex, symptoms, and predisposing factors, were collected via a semi-structured questionnaire. Inclusion and Exclusion Criteria Participants who presented with respiratory symptoms or illnesses and consented to nasopharyngeal swab collection were included, whereas participants without respiratory symptoms or a diagnosed respiratory disease were excluded. For children, written informed consent was obtained from parents or guardians, whereas adults provided their own written consent. Additionally, individuals who declined consent or nasopharyngeal swab collection were not included in the study. Sample size calculation The sample size for this study was based on Fisher's formula: n = z 2 pq/d 2 . Using a prevalence of 8.1% reported by Joseph et al. [ 20 ], a type I error rate of 5%, absolute error or precision rate of 5%, the required sample size was determined to be 114. However, a sample size of 400 participants was planned to be included in the study. Participant Sampling and Study Procedure Nasopharyngeal swabs were collected from all participants using sterile swabs. The participants were categorized into two groups: those with respiratory symptoms but no diagnosed respiratory disease and those with both respiratory symptoms and a diagnosed respiratory disease. The samples were transferred to vials containing normal saline, temporarily stored at 4°C in a cold chain box, and subsequently transported to the laboratory for storage at − 30°C before molecular analysis. To ensure biosafety, all the samples were heat-inactivated at 65°C for 10 minutes before processing. Laboratory analyses were conducted in a Biosafety Level 2 facility at the Molecular Research Laboratory, Department of Microbiology, Lagos State University, Ojo, Nigeria. RNA Extraction and Human Bocavirus Detection DNA was extracted from 200 µL of inactivated nasopharyngeal samples using the Add Bio Extraction Kit (Add-Bio Corporation, Korea) following the manufacturer’s instructions. The extracted nucleic acids were stored at − 20°C before use. Human bocavirus (HBoV) DNA was detected using the Luna Universal Probe qPCR Master Mix (New England BioLabs Inc., USA). The assay targeted the conserved NP1 gene region with specific primers (HBoVF: 5'-GAG-AGA-GGC-TCG-GGC-TCA-TA-3'; HBoVR: 5'-TCG-AAG-CAG-TGC-AAG-ACG-AT-3') and a probe (5'-FAM-CAT-CAG-GAA-CAC-CCA-ATC-AGC-CAC-C-3'-BHQ). PCR amplification was performed on a Rotor-Gene Q real-time PCR platform (Qiagen, Germany). Samples with a cycle threshold (Ct) value of < 40 were considered positive. Data analysis The data were entered into Microsoft Excel and validated for accuracy. Statistical analyses were conducted using SPSS version 22.0 (IBM Corp., USA). The chi-square test was used to assess group differences, with statistical significance set at P < 0.05. Ethical considerations The study adhered to the principles outlined in the Declaration of Helsinki and was approved by the Health Research and Ethics Committee of Lagos State University (Approval Number: LASU/22/REC/001). All participant data were anonymized to ensure confidentiality, and written informed consent was obtained from all participants or their guardians. Results Characteristics of screened participants A total of 400 patients were enrolled, of whom 138 (34.5%) had at least one diagnosed respiratory disease and were categorized as participants with respiratory disease, whereas 254 (63.5%) participants did not have respiratory disease but presented with only respiratory symptoms. Among the recruited participants whose specimens were assayed, 208 (52%) were males, whereas 192 (48%) were females. The age distribution among the recruited participants varied. The highest participation rate was observed among children under 10 years of age, comprising 203 individuals (50.8%). Participation progressively decreased with age, reaching the lowest level of 10 individuals (2.5%) among those aged 40 years and older, as shown in Table 1 . Among those with diagnosed respiratory disease, 10.8% (22) were within the 40 years. Among those without respiratory disease, 69.1% (181) were aged 40 years. Clinical characteristics of participants with diagnosed respiratory disease The frequency of respiratory symptoms of fever was 100% (2/2) among participants ≤ 10 years positive for HBoV compared with 50 (10/20) and 65% (13/20) positive for the common cold and fever, respectively. Among both positive and negative participants aged 11–20 years, 62.5 (5/8) and 62.9% (22/35) presented with fever, respectively. Among those within the 21–30 years age group, common cold and fever occurred more frequently in 61.5% (8/13) of those positive for HBoV than in 55.9% (19/34) of those negative for HBoV. One-third of the participants (33.3%) in the 31–40 year age group had all the respiratory symptoms among those positive for HBoV, whereas 35.7% (5/14) of the participants negative for HBoV presented with common cold, runny nose, and dyspnoea. Among the two persons > 40 years of age, 50% had all symptoms except cough, whereas 71.4% (5/7) of the participants with common cold, runny nose, and dyspnoea were negative for HBoV (Fig. 1 A and B). The frequency of respiratory disease varied in this population. Among the participants with pneumonia, 100% (2/2) were positive for HBoV, whereas 60% (12/20) of those with disease ≤ 10 years without HBoV were positive for bronchiolitis and congestive heart failure. Participants aged 11–20 years had pneumonia more commonly among those who were HBoV positive (62.5%; 5/8) or negative (62.9%; 22/35). Those within the 21–30 years age groups had congestive heart failure and pneumonia more commonly than did those without HBoV, at 61.5% (8/13), with congestive heart failure at 76.5% (26/34) and bronchiolitis and pneumonia at 55.9% (19/34) of the participants, as shown in Fig. 1 A and B. There was no clear distinction between participants who were positive for HBoV because all respiratory diseases were present among one-third (33.3%) of the participants compared with 50 (7/14) and 85.7% (12/14) of the participants who were negative for bronchiolitis and congestive heart failure, respectively. The two participants who were 40 years and older positive for HBoV had asthma compared with pneumonia (57.1%; 4/7), congestive heart failure (71.4%; 5/7), and bronchiolitis (85.7%; 6/7). Clinical characteristics of participants without respiratory disease Among those ≤ 10 years of age, 53.3% (8/15) of the participants who did not present with respiratory disease and who were positive for HBoV had runny nose and fever, whereas 45.8% (76/166) had runny nose and fever (47%; 78/166) and cough (48.8%; 81/166) among the HBoV-negative participants. Those positive for HBoV within the 11–20 years age group had a runny nose and dyspnoea more frequently in 50% (3/6) and 66.7% (4/6) of the participants, respectively, than did those positive for cough, fever, dyspnoea, and runny nose, with a frequency of occurrence between 36.7 (22/60) and 46.7% (28/60), as shown in Fig. 2 A and B. Those within the 21–30 years age group who were negative for HBoV had runny nose and dyspnoea (55.6%; 5/9) as well as the common cold (66.7%; 6/9). Half of the participants who were between 31 and 40 years negative for the HBoV had a common cold, runny nose, and dyspnoea (50%), as shown in Fig. 2 B. Prevalence of Human Bocavirus The overall prevalence of human bocavirus was 12.5% (57/400) among all participants recruited. The sex-related prevalence rates were 13.0% (27/208) and 12.0% (23/192) among males and females, respectively. The prevalence of HBoV varied among the different age groups, with a prevalence of 24.6% (14/57), followed by those 40 years and older, with a prevalence of 20.0% (2/10), although the lowest prevalence was observed among the age groups ≤ 10 years, with a prevalence of 8.4% (17/203), which had the highest prevalence in the study. The prevalence of HBoV differed between those with respiratory disease and those without respiratory disease. Among those who had respiratory disease, the prevalence was 20.3%, whereas the prevalence was 8.4% among those without respiratory disease (χ2 = 11.69, p value = 0.0006), as shown in Table 2 . The prevalence of HBoV also differed among the different age groups within the group that had respiratory disease compared to those without respiratory disease, as depicted in Table 1 . The HBoV highest prevalence of 27.7% (13/47) was observed among the 21–30 year age group, whereas the lowest prevalence of 9.1% (2/22) was observed among participants ≤ 10 years of age among those who had respiratory disease. The prevalence observed among those without respiratory disease ranged from zero (0%) among those aged 31 years and above to the highest prevalence of 10% (1/10) among those aged 21–30 years (Table 1 ). Table 2 Comparison of human bocavirus infection among participants diagnosed with and without respiratory disease in Lagos, Nigeria. Health Status HBoV Positive HBoV Negative Diagnosed Respiratory Disease 28 110 No respiratory disease 22 240 χ2 = 11.69, p value = 0.0006; sensitivity = 0.56, specificity = 0.6857, PPV = 0.2029, NPV = 0.916, Likelihood ratio = 1.782. Discussion This study evaluated the prevalence of HBoV among those diagnosed with respiratory disease and non-diseased participants who visited health facilities in Lagos, Nigeria. An overall prevalence of 12.5% was recorded among all participants in this study, which indicates the circulation of human bocavirus among individuals in Lagos, Nigeria. The majority of published investigations conducted outside of Nigeria have focused on HBoV infection in new-borns and young children [ 22 – 27 ]. Few published studies have been carried out in different countries that have reported the prevalence of HBoV among all age groups [ 21 , 28 ], as observed in this study. The prevalence obtained in this study is higher than the 8.1% reported by Joseph et al. [ 20 ] in Ibadan, Nigeria. The work of Akinloye et al. [ 19 ], who previously reported the commonality of human bocavirus among other respiratory viruses, suggested that there is circulation of HBoV in our population. The dynamics of the spread of the HBoV across different locations in Africa (Cameroon-Kenmoe et al., [ 29 ]; Kenya-Symekher et al., [ 30 ]; Gabon-Lekana Douki et al., [ 31 ]; Egypt-Abdel-Moneim et al., [ 32 ]; Tunisia-Kapoor et al., [ 14 ]) and other parts of the world (Croatia-Ljubin-Sternak et al., [ 25 ]; China-Ji et al., [ 26 ]). The epidemiology of HBoV suggests that this seemingly docile virus may contribute to respiratory infection and disease. The extent to which HBoV contributes to respiratory infection and disease among this population is evident in the detection of this virus among different age groups with and without diagnosed respiratory disease. This study revealed the highest participation among those younger than 20 years, with prevalence rates of 9.1% and 18.6%, respectively, among participants younger than 10 years and those aged 11 and 20 years among those who had respiratory disease (Table 1 ). Compared with those who were not diagnosed with respiratory disease, participants who were younger than 10 years old had a prevalence of 8.3%, as did those between the ages of 11 and 20 years, with a prevalence of 9.1% (Table 1 ). Among both participants with respiratory disease and those without respiratory disease, the prevalence of human bocavirus increased in participants up to the age of 30 years. However, other participants above 30 years of age had low participation in this study, probably because respiratory concerns that attract clinical attention are not common in older adults in our setting. In previous work on human Bocavirus by Arnott et al. [ 21 ] in Cambodia and Misigo et al. [ 28 ] in Kenya, although they tested for the virus among a few adults, the epidemiological details of participants with respect to the specific age groups were obscured in their submissions. This could be due to the retrospective nature of both studies, which is different from the prospective nature of this study. The clinical symptom that was commonly presented among those with respiratory disease was fever among those ≤ 20 years who were infected with human bocavirus, whereas symptoms such as the common cold, runny nose, and fever were common among the same age group that was negative for human bocavirus in their respiratory tract. This is an indication that the onset of fever > 38°C can characterize human Bocavirus infection. Multiple factors can lead to the onset of fever, including the presence of other microbes associated with the respiratory tract. Misigo and colleagues [ 28 ] noted that participants who were all children under 2 years of age more commonly had fever > 38°C, cough, nasal stiffness and runny nose. The commonality of fever in the work of Misingo et al. [ 28 ] compared with this study is consistent. There was an increase in multiple respiratory symptoms and diseases among participants in the 21–30 years age group in this study. These were children born between 1983 and 1993 when there was tough economic stress in the country, and the number of undernourished people in Nigeria was said to have doubled during this period. However, the exact reason for this observation cannot be ascertained. It is suggested that other lifestyle activities could also predispose these individuals to respiratory infections such as human Bocavirus. The respiratory diseases observed in this study were fairly represented among all age groups and included congestive heart failure, bronchiolitis, and pneumonia among participants regardless of the presence of human bocavirus in their respiratory tract. In the work of Arnott et al., bronchiolitis, bronchitis and pneumonia were also associated with infections with human bocavirus, although coinfections with other respiratory viruses, such as human rhinovirus, parainfluenza 3 and respiratory syncytial virus, were established. Coinfection with other viruses was considered in this study. Among participants less than 10 years old without respiratory disease who had human bocavirus detected in their respiratory specimens, running nose and fever were the most common symptoms, whereas among participants who were negative for human bocavirus, the most common symptoms were runny nose, fever, and cough (Fig. 2 a & 2 b). Participants within the age group positive for human bocavirus had runny noses and dyspnoea more frequently than did participants who tested negative for human bocavirus, with frequent symptoms of runny nose, cough, fever, and dyspnoea. The results from this study show that HBoV is present in those with and without respiratory disease who exhibit symptoms. Therefore, the contribution of HBoV as well as its nosocomial spread with and without other respiratory infections in healthcare settings is possible. This has been substantiated by the findings of Kobayashi et al. [ 33 ] and Lee et al. [ 34 ], who recommended preventive measures to prevent nosocomial spread of infection. There was a statistically significant difference (χ2 = 11.69, p value = 0.0006) when those who were positive for human bocavirus (20.3%) were compared with those without respiratory disease but positive for human bocavirus (8.4%), as shown in Table 2 . This result further indicates that human bocavirus contributes to respiratory infection in this population. This study is limited in the wholistic consideration of other respiratory infections of viral or bacterial origin, as the focus of this study was only on human bocavirus. Owing to limited resources, this study did not perform sequencing of positive amplicons to identify the specific strain of HBoV in circulation. It was also not our intention to assess the seasonality of HBoV infection in our settings. We reported an increased prevalence of 14%, which is dissimilar to studies conducted by Joseph et al. [ 20 ] and Akinloye et al. [ 19 ] in the country, Symekher et al. [ 30 ] in Kenya, and Lekana Douki et al. [ 31 ] in Gabon, which can be justified by the different sampling methods, geographical locations, climatic conditions, and study populations examined. Our findings were consistent with those of Abdel-Moneim et al. [ 32 ] in Egypt, Kapoor et al. [ 14 ] in Tunisia, Ljubin-Sternak et al. [ 25 ] in Croatia, Ji et al. [ 26 ] in China, and Kenmoe et al. [ 29 ] in Cameroon. Conclusions This study revealed the significant presence of human bocavirus among individuals with respiratory symptoms in Lagos, Nigeria, with an overall prevalence of 12.5%. The virus was more prevalent in participants with respiratory disease than in those without, demonstrating its likely role in contributing to respiratory illnesses. The higher prevalence observed in young adults suggests age-related vulnerability and possibly lifestyle-related exposure factors. These findings also emphasize the need for enhanced surveillance of HBoV, including its potential for nosocomial spread and its interaction with other respiratory pathogens. Future research should focus on sequencing studies to identify circulating strains and a broader assessment of coinfections to fully elucidate the clinical and epidemiological significance of HBoV in this region. Declarations Ethics approval and consent to participate: Ethical approval was granted by the Health Research and Ethics Committee of Lagos State University (Approval Number: LASU/22/REC/001). Consent for publication: Oral and written informed consents were obtained from all the participants and appropriately documented. Availability of data and materials: The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing interests: The authors declare that they have no competing interests. Funding: No funding was received for the current study. Authors' contributions: AAA carried out conception, design of the work, acquisition, analysis, interpretation of data; drafted the work and revised it. OSA carried out analysis of the software used in the work, interpretation of data, and substantively revised it. EJ participated in acquisition, analysis, interpretation of data, and initial draft. AOA participated in acquisition, analysis, interpretation of data, and initial draft. TAB participated in acquisition, analysis, interpretation of data, and initial draft. ZBS participated in acquisition, analysis, interpretation of data, and initial draft. KOA participated in acquisition, interpretation of data and quality control. All authors approved the submitted version. Acknowledgements: We hereby acknowledge the Department of Microbiology and the Lagos State University management including the ethical review board for their support and for the approval to undergo this current study. All the study participants are specially acknowledged for accepting to be part of the research. Authors' information: AAA is the Team Leader for Influenza & Other Respiratory Tract Viruses (IORTV) research at the Lagos State University. He received the Global Virus Network training scholarship for Emerging Leaders in Virology at the Institute of Human Virology, University of Maryland School of Medicine; Johns Hopkins Bloomberg School of Public Health, Baltimore; and National Institutes of Health (NIH), Bethesda, USA; and a training fellowship at the Luxembourg Institute of Health WHO influenza reference Laboratory; before obtaining a further training at the ISIRV/ Christian Medical College (CMC) Respiratory Virus School in Vellore, India. OSA is a Medical/Molecular Virologist with research on virus and other infectious diseases and a Lecturer in the Department of Biological Sciences and Biotechnology, Caleb University, Lagos. EJ is an MSc graduate in Microbiology with research in molecular virology under the supervision of AAA. AOA is a BSc graduate in Microbiology with research in molecular virology under the supervision of AAA. 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Human bocavirus infection and respiratory tract disease identified in a UK patient cohort. J Clin Virol. 2020;129:104453. Misigo D, Mwaengo D, Mburu D. Molecular detection and phylogenetic analysis of Kenyan human bocavirus isolates. J Infect Developing Ctries. 2014;8(02):221–7. Kenmoe S, Tchendjou P, Vernet MA, Moyo-Tetang S, Mossus T, Njankouo-Ripa M, Kenne A, Penlap Beng V, Vabret A, Njouom R. Viral etiology of severe acute respiratory infections in hospitalized children in Cameroon, 2011–2013. Influenza Other Respir Viruses. 2016;10(5):386–93. Symekher SML, Gachara G, Simwa JM, Gichogo J, Rotich M, Ng’ayo MO, Magana J. Human bocavirus infection in children with acute respiratory infection in Nairobi, Kenya. Open Journal of Medical Microbiology 2013, 2013. Lekana-Douki SE, Behillil S, Enouf V, Leroy EM, Berthet N. Detection of human bocavirus-1 in both nasal and stool specimens from children under 5 years old with influenza-like illnesses or diarrhea in Gabon. BMC Res Notes. 2018;11:1–7. Abdel-Moneim AS, Kamel MM, Hamed DH, Hassan SS, Soliman MS, Al-Quraishy SA, El Kholy AA. A novel primer set for improved direct gene sequencing of human bocavirus genotype-1 from clinical samples. J Virol Methods. 2016;228:108–13. Kobayashi H, Shinjoh M, Sudo K, Kato S, Morozumi M, Koinuma G, Takahashi T, Takano Y, Tamura Y, Hasegawa N. Nosocomial infection by human bocavirus and human rhinovirus among paediatric patients with respiratory risks. J Hosp Infect. 2019;103(3):341–8. Lee HN, Koo HJ, Kim SH, Choi S-H, Sung H, Do K-H. Human bocavirus infection in adults: clinical features and radiological findings. Korean J Radiol. 2019;20(7):1226–35. Tables Table 1 is available in the Supplementary Files section. 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-5997893","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":416745703,"identity":"09750ae2-962c-44c4-a9b7-d4b627c40751","order_by":0,"name":"Abdul-Azeez A. ANJORIN","email":"data:image/png;base64,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","orcid":"","institution":"Lagos State University","correspondingAuthor":true,"prefix":"","firstName":"Abdul-Azeez","middleName":"A.","lastName":"ANJORIN","suffix":""},{"id":416745704,"identity":"f7aa397f-1755-4260-b90a-ab836581eeb4","order_by":1,"name":"Oluwaseyi S. ASHAKA","email":"","orcid":"","institution":"Caleb University","correspondingAuthor":false,"prefix":"","firstName":"Oluwaseyi","middleName":"S.","lastName":"ASHAKA","suffix":""},{"id":416745705,"identity":"40256364-aa07-42d8-9301-0029144cf656","order_by":2,"name":"Joseph EYEDO","email":"","orcid":"","institution":"Lagos State University","correspondingAuthor":false,"prefix":"","firstName":"Joseph","middleName":"","lastName":"EYEDO","suffix":""},{"id":416745706,"identity":"85976b15-33c7-4e3c-8286-81eccf33e09a","order_by":3,"name":"Abdulrauf O. ABDULKAREEM","email":"","orcid":"","institution":"Lagos State University","correspondingAuthor":false,"prefix":"","firstName":"Abdulrauf","middleName":"O.","lastName":"ABDULKAREEM","suffix":""},{"id":416745707,"identity":"fc700193-f3a9-4031-92d6-e91614fd5394","order_by":4,"name":"Taofeeq A. BALOGUN","email":"","orcid":"","institution":"Lagos State University","correspondingAuthor":false,"prefix":"","firstName":"Taofeeq","middleName":"A.","lastName":"BALOGUN","suffix":""},{"id":416745708,"identity":"93eed8ca-a53b-482f-9bd7-6e71932a90a0","order_by":5,"name":"Zainab B. SALAMI","email":"","orcid":"","institution":"Lagos State University","correspondingAuthor":false,"prefix":"","firstName":"Zainab","middleName":"B.","lastName":"SALAMI","suffix":""},{"id":416745709,"identity":"a4556344-afcf-4c62-8352-006441c9620a","order_by":6,"name":"Kabiru Akinyemi","email":"","orcid":"","institution":"Lagos State University","correspondingAuthor":false,"prefix":"","firstName":"Kabiru","middleName":"","lastName":"Akinyemi","suffix":""}],"badges":[],"createdAt":"2025-02-10 09:53:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5997893/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5997893/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":76687870,"identity":"0236e6f2-9635-4166-9516-19b65852b517","added_by":"auto","created_at":"2025-02-19 16:28:15","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":125081,"visible":true,"origin":"","legend":"\u003cp\u003eFrequencies of respiratory symptoms among those diagnosed with respiratory disease among different age groups. A. Patients who were positive for HBoV and had respiratory disease. B. Patients who were negative for HBoV and hadrespiratory disease.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-5997893/v1/be6070b068113584131010f6.png"},{"id":76687865,"identity":"4377059c-7187-49d6-bbb0-6504ccb1088b","added_by":"auto","created_at":"2025-02-19 16:28:15","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":89451,"visible":true,"origin":"","legend":"\u003cp\u003eFrequencies of respiratory symptoms among those without respiratory disease indifferent age groups. A. Patients who were positive for HBoV and had no respiratory disease. B. Patients who were negative for HBoV without respiratory disease.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-5997893/v1/d0c01dfc2810a76cd025ae3a.png"},{"id":76689542,"identity":"38c4c821-7245-4061-83ab-93bf685cbc5a","added_by":"auto","created_at":"2025-02-19 16:44:15","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":971279,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5997893/v1/f5a7d44c-8d4c-4ae0-b72a-b531342e2de3.pdf"},{"id":76687861,"identity":"a6f3dd55-779f-41e2-a683-0377e1674a4c","added_by":"auto","created_at":"2025-02-19 16:28:15","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":16454,"visible":true,"origin":"","legend":"","description":"","filename":"Table1.docx","url":"https://assets-eu.researchsquare.com/files/rs-5997893/v1/9516c501e72c20d91340b5b3.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Human Bocavirus as a Contributor to Respiratory Disease in Lagos, Nigeria: A Hospital-Based Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eGlobally, zoonotic diseases are responsible for an estimated one billion cases of illness and millions of fatalities annually. Scientific evidence suggests that three out of every four emerging infectious diseases are zoonotic in origin, with over half of these infections transmitted from animals to humans [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Bocavirus, a virus with zoonotic origins, derives its name from the canine minute virus and bovine parvovirus, highlighting its evolutionary lineage [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Human Bocavirus (HBoV), a member of the \u003cem\u003eParvoviridae\u003c/em\u003e family and \u003cem\u003eParvovirinae\u003c/em\u003e subfamily, is a single-stranded DNA virus that is consistent with other viruses in this family.\u003c/p\u003e \u003cp\u003eHBoV primarily causes acute respiratory tract infections across all age groups, with severe infections more commonly reported at the extremes of age [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The virus was first isolated from a nasopharyngeal specimen from an infant with respiratory disease and has since garnered significant attention [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Globally, the prevalence of HBoV is estimated at approximately 6%, with reports of infections resulting in fatalities [\u003cspan additionalcitationids=\"CR8 CR9\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHBoV comprises four genotypes, each distinguishable by its route of infection. While HBoV-1 is associated primarily with respiratory infections, HBoV-2 to HBoV-4 are more frequently linked to gastrointestinal infections. The evidence indicates that HBoV may persist in the respiratory tract post-infection, with low-level viremia detectable for months. However, the clinical significance of HBoV is often questioned because of its frequent co-detection with other respiratory viruses [\u003cspan additionalcitationids=\"CR12\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe role of HBoV in gastrointestinal infections has also been investigated, with viral detection in stool samples suggesting a possible fecal-oral transmission route [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. However, its exact contribution to gastroenteritis remains undefined. The detection of HBoV in both symptomatic and asymptomatic individuals further complicates its association with specific diseases [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eNotably, HBoV has been detected in diverse samples, including blood, cerebrospinal fluid, urine, saliva, tonsils, and even environmental samples. This wide detection spectrum may reflect viral persistence post-exposure, akin to its Parvovirus B19 relative, although definitive conclusions remain elusive [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eStudies on HBoV prevalence and genetic diversity have been conducted globally, yielding various results. In Nigeria, a prevalence of 2.4% was reported among children with acute respiratory infections in Oyo State, with coinfections involving other respiratory viruses being common [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Another Nigerian study reported an 8.1% prevalence of HBoV-1 in children with respiratory tract infections [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Internationally, Arnott et al. [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] reported a 1.5% prevalence in Cambodian patients with pneumonia, whereas Alkhalf et al. [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e] reported a 1.6% prevalence among children with respiratory symptoms in Saudi Arabia.\u003c/p\u003e \u003cp\u003eDespite these findings, there is limited information on the prevalence of HBoV in Lagos, a cosmopolitan hub in Nigeria. Previous studies in Nigeria have focused predominantly on pediatric populations, leaving a significant gap in understanding the prevalence of HBoV across all age groups.\u003c/p\u003e \u003cp\u003eThis study therefore assessed the prevalence of HBoV across diverse age strata in individuals presenting with respiratory infections in Lagos, Nigeria. This study provides insights into the contribution of HBoV to respiratory illnesses among hospital attendees, addressing a critical gap in the epidemiological understanding of this virus in the region.\u003c/p\u003e"},{"header":"Participants and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design and Population\u003c/h2\u003e \u003cp\u003eThis was a hospital-based, cross-sectional prospective study conducted between December 2022 and May 2023. The study included participants of all age groups who visited selected healthcare facilities in Lagos, Nigeria, for respiratory illnesses. Three primary healthcare centers- Agbede Primary Health Center (Ikorodu), Iba Primary Health Center (Ojo), and Lagos State University Health Center- were purposively selected to represent diverse patient demographics, including those of children and adults.\u003c/p\u003e \u003cp\u003eAdditionally, Lagos State University Teaching Hospital, the only tertiary healthcare facility in the area, was included to capture urban populations and cases requiring advanced care.\u003c/p\u003e \u003cp\u003eParticipants were consecutively recruited during routine medical visits. Demographic and clinical data, including age, sex, symptoms, and predisposing factors, were collected via a semi-structured questionnaire.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eInclusion and Exclusion Criteria\u003c/h3\u003e\n\u003cp\u003eParticipants who presented with respiratory symptoms or illnesses and consented to nasopharyngeal swab collection were included, whereas participants without respiratory symptoms or a diagnosed respiratory disease were excluded. For children, written informed consent was obtained from parents or guardians, whereas adults provided their own written consent. Additionally, individuals who declined consent or nasopharyngeal swab collection were not included in the study.\u003c/p\u003e\n\u003ch3\u003eSample size calculation\u003c/h3\u003e\n\u003cp\u003eThe sample size for this study was based on Fisher's formula: n\u0026thinsp;=\u0026thinsp;z\u003csup\u003e2\u003c/sup\u003epq/d\u003csup\u003e2\u003c/sup\u003e. Using a prevalence of 8.1% reported by Joseph et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], a type I error rate of 5%, absolute error or precision rate of 5%, the required sample size was determined to be 114. However, a sample size of 400 participants was planned to be included in the study.\u003c/p\u003e\n\u003ch3\u003eParticipant Sampling and Study Procedure\u003c/h3\u003e\n\u003cp\u003e Nasopharyngeal swabs were collected from all participants using sterile swabs. The participants were categorized into two groups: those with respiratory symptoms but no diagnosed respiratory disease and those with both respiratory symptoms and a diagnosed respiratory disease. The samples were transferred to vials containing normal saline, temporarily stored at 4\u0026deg;C in a cold chain box, and subsequently transported to the laboratory for storage at \u0026minus;\u0026thinsp;30\u0026deg;C before molecular analysis.\u003c/p\u003e \u003cp\u003eTo ensure biosafety, all the samples were heat-inactivated at 65\u0026deg;C for 10 minutes before processing. Laboratory analyses were conducted in a Biosafety Level 2 facility at the Molecular Research Laboratory, Department of Microbiology, Lagos State University, Ojo, Nigeria.\u003c/p\u003e\n\u003ch3\u003eRNA Extraction and Human Bocavirus Detection\u003c/h3\u003e\n\u003cp\u003eDNA was extracted from 200 \u0026micro;L of inactivated nasopharyngeal samples using the Add Bio Extraction Kit (Add-Bio Corporation, Korea) following the manufacturer\u0026rsquo;s instructions. The extracted nucleic acids were stored at \u0026minus;\u0026thinsp;20\u0026deg;C before use.\u003c/p\u003e \u003cp\u003eHuman bocavirus (HBoV) DNA was detected using the Luna Universal Probe qPCR Master Mix (New England BioLabs Inc., USA). The assay targeted the conserved NP1 gene region with specific primers (HBoVF: 5'-GAG-AGA-GGC-TCG-GGC-TCA-TA-3'; HBoVR: 5'-TCG-AAG-CAG-TGC-AAG-ACG-AT-3') and a probe (5'-FAM-CAT-CAG-GAA-CAC-CCA-ATC-AGC-CAC-C-3'-BHQ). PCR amplification was performed on a Rotor-Gene Q real-time PCR platform (Qiagen, Germany). Samples with a cycle threshold (Ct) value of \u0026lt;\u0026thinsp;40 were considered positive.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eData analysis\u003c/h2\u003e \u003cp\u003eThe data were entered into Microsoft Excel and validated for accuracy. Statistical analyses were conducted using SPSS version 22.0 (IBM Corp., USA). The chi-square test was used to assess group differences, with statistical significance set at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eEthical considerations\u003c/h3\u003e\n\u003cp\u003e The study adhered to the principles outlined in the Declaration of Helsinki and was approved by the Health Research and Ethics Committee of Lagos State University (Approval Number: LASU/22/REC/001). All participant data were anonymized to ensure confidentiality, and written informed consent was obtained from all participants or their guardians.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003eCharacteristics of screened participants\u003c/h2\u003e\n \u003cp\u003eA total of 400 patients were enrolled, of whom 138 (34.5%) had at least one diagnosed respiratory disease and were categorized as participants with respiratory disease, whereas 254 (63.5%) participants did not have respiratory disease but presented with only respiratory symptoms. Among the recruited participants whose specimens were assayed, 208 (52%) were males, whereas 192 (48%) were females. The age distribution among the recruited participants varied. The highest participation rate was observed among children under 10 years of age, comprising 203 individuals (50.8%). Participation progressively decreased with age, reaching the lowest level of 10 individuals (2.5%) among those aged 40 years and older, as shown in Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eAmong those with diagnosed respiratory disease, 10.8% (22) were within the \u0026lt;\u0026thinsp;10 years age group, 39.4% (43/138) were within the 11\u0026ndash;20 years age range, 82.5% (47) were within the 21\u0026ndash;30 years age range, 81.0% (17) were within the 31\u0026ndash;40 years age range, and 90.0% (9) were \u0026gt;\u0026thinsp;40 years. Among those without respiratory disease, 69.1% (181) were aged\u0026thinsp;\u0026lt;\u0026thinsp;10 years, 25.2% (66) were aged 11\u0026ndash;20 years, 3.8% (10) were aged 21\u0026ndash;30 years, 1.5% (4) were aged 31\u0026ndash;40 years, and 0.4% (1) were aged\u0026thinsp;\u0026gt;\u0026thinsp;40 years.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eClinical characteristics of participants with diagnosed respiratory disease\u003c/h2\u003e\n \u003cp\u003eThe frequency of respiratory symptoms of fever was 100% (2/2) among participants\u0026thinsp;\u0026le;\u0026thinsp;10 years positive for HBoV compared with 50 (10/20) and 65% (13/20) positive for the common cold and fever, respectively. Among both positive and negative participants aged 11\u0026ndash;20 years, 62.5 (5/8) and 62.9% (22/35) presented with fever, respectively. Among those within the 21\u0026ndash;30 years age group, common cold and fever occurred more frequently in 61.5% (8/13) of those positive for HBoV than in 55.9% (19/34) of those negative for HBoV. One-third of the participants (33.3%) in the 31\u0026ndash;40 year age group had all the respiratory symptoms among those positive for HBoV, whereas 35.7% (5/14) of the participants negative for HBoV presented with common cold, runny nose, and dyspnoea. Among the two persons\u0026thinsp;\u0026gt;\u0026thinsp;40 years of age, 50% had all symptoms except cough, whereas 71.4% (5/7) of the participants with common cold, runny nose, and dyspnoea were negative for HBoV (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA and B).\u003c/p\u003e\n \u003cp\u003eThe frequency of respiratory disease varied in this population. Among the participants with pneumonia, 100% (2/2) were positive for HBoV, whereas 60% (12/20) of those with disease\u0026thinsp;\u0026le;\u0026thinsp;10 years without HBoV were positive for bronchiolitis and congestive heart failure. Participants aged 11\u0026ndash;20 years had pneumonia more commonly among those who were HBoV positive (62.5%; 5/8) or negative (62.9%; 22/35). Those within the 21\u0026ndash;30 years age groups had congestive heart failure and pneumonia more commonly than did those without HBoV, at 61.5% (8/13), with congestive heart failure at 76.5% (26/34) and bronchiolitis and pneumonia at 55.9% (19/34) of the participants, as shown in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003eA and B. There was no clear distinction between participants who were positive for HBoV because all respiratory diseases were present among one-third (33.3%) of the participants compared with 50 (7/14) and 85.7% (12/14) of the participants who were negative for bronchiolitis and congestive heart failure, respectively. The two participants who were 40 years and older positive for HBoV had asthma compared with pneumonia (57.1%; 4/7), congestive heart failure (71.4%; 5/7), and bronchiolitis (85.7%; 6/7).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003eClinical characteristics of participants without respiratory disease\u003c/h2\u003e\n \u003cp\u003eAmong those\u0026thinsp;\u0026le;\u0026thinsp;10 years of age, 53.3% (8/15) of the participants who did not present with respiratory disease and who were positive for HBoV had runny nose and fever, whereas 45.8% (76/166) had runny nose and fever (47%; 78/166) and cough (48.8%; 81/166) among the HBoV-negative participants. Those positive for HBoV within the 11\u0026ndash;20 years age group had a runny nose and dyspnoea more frequently in 50% (3/6) and 66.7% (4/6) of the participants, respectively, than did those positive for cough, fever, dyspnoea, and runny nose, with a frequency of occurrence between 36.7 (22/60) and 46.7% (28/60), as shown in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eA and B. Those within the 21\u0026ndash;30 years age group who were negative for HBoV had runny nose and dyspnoea (55.6%; 5/9) as well as the common cold (66.7%; 6/9). Half of the participants who were between 31 and 40 years negative for the HBoV had a common cold, runny nose, and dyspnoea (50%), as shown in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003eB.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003ePrevalence of Human Bocavirus\u003c/h2\u003e\n \u003cp\u003eThe overall prevalence of human bocavirus was 12.5% (57/400) among all participants recruited. The sex-related prevalence rates were 13.0% (27/208) and 12.0% (23/192) among males and females, respectively. The prevalence of HBoV varied among the different age groups, with a prevalence of 24.6% (14/57), followed by those 40 years and older, with a prevalence of 20.0% (2/10), although the lowest prevalence was observed among the age groups\u0026thinsp;\u0026le;\u0026thinsp;10 years, with a prevalence of 8.4% (17/203), which had the highest prevalence in the study.\u003c/p\u003e\n \u003cp\u003eThe prevalence of HBoV differed between those with respiratory disease and those without respiratory disease. Among those who had respiratory disease, the prevalence was 20.3%, whereas the prevalence was 8.4% among those without respiratory disease (\u0026chi;2\u0026thinsp;=\u0026thinsp;11.69, p value\u0026thinsp;=\u0026thinsp;0.0006), as shown in Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\n \u003cp\u003eThe prevalence of HBoV also differed among the different age groups within the group that had respiratory disease compared to those without respiratory disease, as depicted in Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. The HBoV highest prevalence of 27.7% (13/47) was observed among the 21\u0026ndash;30 year age group, whereas the lowest prevalence of 9.1% (2/22) was observed among participants\u0026thinsp;\u0026le;\u0026thinsp;10 years of age among those who had respiratory disease. The prevalence observed among those without respiratory disease ranged from zero (0%) among those aged 31 years and above to the highest prevalence of 10% (1/10) among those aged 21\u0026ndash;30 years (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u0026nbsp;\u003c/p\u003e\n \u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of human bocavirus infection among participants diagnosed with and without respiratory disease in Lagos, Nigeria.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" style=\"width: 49.0385%;\"\u003e\n \u003cp\u003eHealth Status\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 24.7596%;\"\u003e\n \u003cp\u003eHBoV Positive\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" style=\"width: 26.2019%;\"\u003e\n \u003cp\u003eHBoV Negative\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 49.0385%;\"\u003e\n \u003cp\u003eDiagnosed Respiratory Disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 24.7596%;\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 26.2019%;\"\u003e\n \u003cp\u003e110\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" style=\"width: 49.0385%;\"\u003e\n \u003cp\u003eNo respiratory disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 24.7596%;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" style=\"width: 26.2019%;\"\u003e\n \u003cp\u003e240\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u0026chi;2\u0026thinsp;=\u0026thinsp;11.69, p value\u0026thinsp;=\u0026thinsp;0.0006; sensitivity\u0026thinsp;=\u0026thinsp;0.56, specificity\u0026thinsp;=\u0026thinsp;0.6857,\u003c/p\u003e\n \u003cp\u003ePPV\u0026thinsp;=\u0026thinsp;0.2029, NPV\u0026thinsp;=\u0026thinsp;0.916, Likelihood ratio\u0026thinsp;=\u0026thinsp;1.782.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study evaluated the prevalence of HBoV among those diagnosed with respiratory disease and non-diseased participants who visited health facilities in Lagos, Nigeria. An overall prevalence of 12.5% was recorded among all participants in this study, which indicates the circulation of human bocavirus among individuals in Lagos, Nigeria. The majority of published investigations conducted outside of Nigeria have focused on HBoV infection in new-borns and young children [\u003cspan additionalcitationids=\"CR23 CR24 CR25 CR26\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Few published studies have been carried out in different countries that have reported the prevalence of HBoV among all age groups [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], as observed in this study.\u003c/p\u003e \u003cp\u003eThe prevalence obtained in this study is higher than the 8.1% reported by Joseph et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] in Ibadan, Nigeria. The work of Akinloye et al. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], who previously reported the commonality of human bocavirus among other respiratory viruses, suggested that there is circulation of HBoV in our population. The dynamics of the spread of the HBoV across different locations in Africa (Cameroon-Kenmoe et al., [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]; Kenya-Symekher et al., [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]; Gabon-Lekana Douki et al., [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]; Egypt-Abdel-Moneim et al., [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]; Tunisia-Kapoor et al., [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]) and other parts of the world (Croatia-Ljubin-Sternak et al., [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]; China-Ji et al., [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]).\u003c/p\u003e \u003cp\u003eThe epidemiology of HBoV suggests that this seemingly docile virus may contribute to respiratory infection and disease. The extent to which HBoV contributes to respiratory infection and disease among this population is evident in the detection of this virus among different age groups with and without diagnosed respiratory disease.\u003c/p\u003e \u003cp\u003eThis study revealed the highest participation among those younger than 20 years, with prevalence rates of 9.1% and 18.6%, respectively, among participants younger than 10 years and those aged 11 and 20 years among those who had respiratory disease (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Compared with those who were not diagnosed with respiratory disease, participants who were younger than 10 years old had a prevalence of 8.3%, as did those between the ages of 11 and 20 years, with a prevalence of 9.1% (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Among both participants with respiratory disease and those without respiratory disease, the prevalence of human bocavirus increased in participants up to the age of 30 years. However, other participants above 30 years of age had low participation in this study, probably because respiratory concerns that attract clinical attention are not common in older adults in our setting.\u003c/p\u003e \u003cp\u003eIn previous work on human Bocavirus by Arnott et al. [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] in Cambodia and Misigo et al. [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] in Kenya, although they tested for the virus among a few adults, the epidemiological details of participants with respect to the specific age groups were obscured in their submissions. This could be due to the retrospective nature of both studies, which is different from the prospective nature of this study.\u003c/p\u003e \u003cp\u003eThe clinical symptom that was commonly presented among those with respiratory disease was fever among those\u0026thinsp;\u0026le;\u0026thinsp;20 years who were infected with human bocavirus, whereas symptoms such as the common cold, runny nose, and fever were common among the same age group that was negative for human bocavirus in their respiratory tract. This is an indication that the onset of fever\u0026thinsp;\u0026gt;\u0026thinsp;38\u0026deg;C can characterize human Bocavirus infection. Multiple factors can lead to the onset of fever, including the presence of other microbes associated with the respiratory tract. Misigo and colleagues [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] noted that participants who were all children under 2 years of age more commonly had fever\u0026thinsp;\u0026gt;\u0026thinsp;38\u0026deg;C, cough, nasal stiffness and runny nose. The commonality of fever in the work of Misingo et al. [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] compared with this study is consistent.\u003c/p\u003e \u003cp\u003eThere was an increase in multiple respiratory symptoms and diseases among participants in the 21\u0026ndash;30 years age group in this study. These were children born between 1983 and 1993 when there was tough economic stress in the country, and the number of undernourished people in Nigeria was said to have doubled during this period. However, the exact reason for this observation cannot be ascertained. It is suggested that other lifestyle activities could also predispose these individuals to respiratory infections such as human Bocavirus.\u003c/p\u003e \u003cp\u003eThe respiratory diseases observed in this study were fairly represented among all age groups and included congestive heart failure, bronchiolitis, and pneumonia among participants regardless of the presence of human bocavirus in their respiratory tract. In the work of Arnott et al., bronchiolitis, bronchitis and pneumonia were also associated with infections with human bocavirus, although coinfections with other respiratory viruses, such as human rhinovirus, parainfluenza 3 and respiratory syncytial virus, were established. Coinfection with other viruses was considered in this study.\u003c/p\u003e \u003cp\u003eAmong participants less than 10 years old without respiratory disease who had human bocavirus detected in their respiratory specimens, running nose and fever were the most common symptoms, whereas among participants who were negative for human bocavirus, the most common symptoms were runny nose, fever, and cough (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea \u0026amp; \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb). Participants within the age group positive for human bocavirus had runny noses and dyspnoea more frequently than did participants who tested negative for human bocavirus, with frequent symptoms of runny nose, cough, fever, and dyspnoea.\u003c/p\u003e \u003cp\u003eThe results from this study show that HBoV is present in those with and without respiratory disease who exhibit symptoms. Therefore, the contribution of HBoV as well as its nosocomial spread with and without other respiratory infections in healthcare settings is possible. This has been substantiated by the findings of Kobayashi et al. [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e] and Lee et al. [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e], who recommended preventive measures to prevent nosocomial spread of infection.\u003c/p\u003e \u003cp\u003eThere was a statistically significant difference (χ2\u0026thinsp;=\u0026thinsp;11.69, p value\u0026thinsp;=\u0026thinsp;0.0006) when those who were positive for human bocavirus (20.3%) were compared with those without respiratory disease but positive for human bocavirus (8.4%), as shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. This result further indicates that human bocavirus contributes to respiratory infection in this population. This study is limited in the wholistic consideration of other respiratory infections of viral or bacterial origin, as the focus of this study was only on human bocavirus. Owing to limited resources, this study did not perform sequencing of positive amplicons to identify the specific strain of HBoV in circulation. It was also not our intention to assess the seasonality of HBoV infection in our settings.\u003c/p\u003e \u003cp\u003eWe reported an increased prevalence of 14%, which is dissimilar to studies conducted by Joseph et al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] and Akinloye et al. [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] in the country, Symekher et al. [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e] in Kenya, and Lekana Douki et al. [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] in Gabon, which can be justified by the different sampling methods, geographical locations, climatic conditions, and study populations examined. Our findings were consistent with those of Abdel-Moneim et al. [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] in Egypt, Kapoor et al. [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] in Tunisia, Ljubin-Sternak et al. [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e] in Croatia, Ji et al. [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] in China, and Kenmoe et al. [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e] in Cameroon.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis study revealed the significant presence of human bocavirus among individuals with respiratory symptoms in Lagos, Nigeria, with an overall prevalence of 12.5%. The virus was more prevalent in participants with respiratory disease than in those without, demonstrating its likely role in contributing to respiratory illnesses. The higher prevalence observed in young adults suggests age-related vulnerability and possibly lifestyle-related exposure factors. These findings also emphasize the need for enhanced surveillance of HBoV, including its potential for nosocomial spread and its interaction with other respiratory pathogens. Future research should focus on sequencing studies to identify circulating strains and a broader assessment of coinfections to fully elucidate the clinical and epidemiological significance of HBoV in this region.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003e Ethical approval was granted by the Health Research and Ethics Committee of Lagos State University (Approval Number: LASU/22/REC/001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eOral and written informed consents were obtained from all the participants and appropriately documented.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials:\u0026nbsp;\u003c/strong\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNo funding was received for the current study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAAA carried out conception, design of the work, acquisition, analysis, interpretation of data; drafted the work and revised it.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOSA carried out analysis of the software used in the work, interpretation of data, and substantively revised it.\u003c/p\u003e\n\u003cp\u003eEJ participated in acquisition, analysis, interpretation of data, and initial draft.\u003c/p\u003e\n\u003cp\u003eAOA participated in acquisition, analysis, interpretation of data, and initial draft.\u003c/p\u003e\n\u003cp\u003eTAB participated in acquisition, analysis, interpretation of data, and initial draft.\u003c/p\u003e\n\u003cp\u003eZBS participated in acquisition, analysis, interpretation of data, and initial draft.\u003c/p\u003e\n\u003cp\u003eKOA participated in acquisition, interpretation of data and quality control.\u003c/p\u003e\n\u003cp\u003eAll authors approved the submitted version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eWe hereby acknowledge the Department of Microbiology and the Lagos State University management including the ethical review board for their support and for the approval to undergo this current study. All the study participants are specially acknowledged for accepting to be part of the research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; information:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAAA is the Team Leader for Influenza \u0026amp; Other Respiratory Tract Viruses (IORTV) research at the Lagos State University. He received the Global Virus Network training scholarship for Emerging Leaders in Virology at the Institute of Human Virology, University of Maryland School of Medicine; Johns Hopkins Bloomberg School of Public Health, Baltimore; and National Institutes of Health (NIH), Bethesda, USA; and a training fellowship at the Luxembourg Institute of Health WHO influenza reference Laboratory; before obtaining a further training at the ISIRV/ Christian Medical College (CMC) Respiratory Virus School in Vellore, India.\u003c/p\u003e\n\u003cp\u003eOSA is a Medical/Molecular Virologist with research on virus and other infectious diseases and a Lecturer in the Department of Biological Sciences and Biotechnology, Caleb University, Lagos.\u003c/p\u003e\n\u003cp\u003eEJ is an MSc graduate in Microbiology with research in molecular virology under the supervision of AAA.\u003c/p\u003e\n\u003cp\u003eAOA is a BSc graduate in Microbiology with research in molecular virology under the supervision of AAA.\u003c/p\u003e\n\u003cp\u003eTAB is a BSc graduate in Microbiology with research in molecular virology under the supervision of AAA.\u003c/p\u003e\n\u003cp\u003eZBS is a BSc graduate in Microbiology with research in molecular virology under the supervision of AAA.\u003c/p\u003e\n\u003cp\u003eKOA is a renowned Professor of Microbiology and a Director at the Lagos State University. He received a postdoctoral fellowship at Universitat Hohenheim, Stuttgart, Germany.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eEsposito MM, Turku S, Lehrfield L, Shoman A. The Impact of Human Activities on Zoonotic Infection Transmissions. Animals: open access J MDPI 2023, 13(10).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeiss RA, Sankaran N. Emergence of epidemic diseases: zoonoses and other origins. Fac reviews. 2022;11:2.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchildgen O, Qiu J, S\u0026ouml;derlund-Venermo M. Genomic features of the human bocaviruses. Future Virol. 2012;7(1):31\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChristensen A, Kesti O, Elenius V, Eskola AL, D\u0026oslash;llner H, Altunbulakli C, Akdis CA, S\u0026ouml;derlund-Venermo M, Jartti T. Human bocaviruses and paediatric infections. 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PLoS Pathog. 2009;5(4):e1000391.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKapoor A, Slikas E, Simmonds P, Chieochansin T, Naeem A, Shaukat S, Masroor Alam M, Sharif S, Angez M, Zaidi S. A newly identified bocavirus species in human stool. J Infect Dis. 2009;199(2):196\u0026ndash;200.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAshaka OS, Salu OB, James AB, Oyefolu AOB, Anjorin AA, Oke BO, Orenolu MR, Omilabu SA. Parvovirus B19 DNA detection in treatment-na\u0026iuml;ve HIV anemic patients in Lagos, Nigeria: a case control study. Afr Health Sci. 2020;20(1):219\u0026ndash;26.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAkinloye OM, R\u0026ouml;nkk\u0026ouml; E, Savolainen-Kopra C, Ziegler T, Iwalokun BA, Deji-Agboola MA, Oluwadun A, Roivainen M, Adu FD, Hovi T. 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Detection of human bocavirus-1 in both nasal and stool specimens from children under 5 years old with influenza-like illnesses or diarrhea in Gabon. BMC Res Notes. 2018;11:1\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbdel-Moneim AS, Kamel MM, Hamed DH, Hassan SS, Soliman MS, Al-Quraishy SA, El Kholy AA. A novel primer set for improved direct gene sequencing of human bocavirus genotype-1 from clinical samples. J Virol Methods. 2016;228:108\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKobayashi H, Shinjoh M, Sudo K, Kato S, Morozumi M, Koinuma G, Takahashi T, Takano Y, Tamura Y, Hasegawa N. Nosocomial infection by human bocavirus and human rhinovirus among paediatric patients with respiratory risks. J Hosp Infect. 2019;103(3):341\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee HN, Koo HJ, Kim SH, Choi S-H, Sung H, Do K-H. 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Korean J Radiol. 2019;20(7):1226\u0026ndash;35.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Human Bocavirus (HBoV), Respiratory disease, Prevalence, Molecular detection, Nigeria","lastPublishedDoi":"10.21203/rs.3.rs-5997893/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5997893/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eHuman Bocavirus (HBoV) is a single-stranded DNA virus from the Parvoviridae family that is associated with respiratory and gastrointestinal infections. The prevalence and impact of the HBoV in Lagos, Nigeria, particularly across all age groups, remain underexplored.\u003c/p\u003e\u003ch2\u003eAim\u003c/h2\u003e \u003cp\u003eThis study aimed to determine the prevalence of HBoV among individuals with respiratory symptoms in Lagos, Nigeria, and its association with respiratory disease.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA hospital-based, cross-sectional study was conducted from December 2022 to May 2023 in Lagos. Nasopharyngeal swabs were collected from 400 participants presenting with respiratory symptoms across diverse age groups. The samples were analysed for HBoV DNA using real-time PCR. Demographic and clinical data were recorded, and statistical analysis was performed using SPSS.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe overall prevalence of HBoV was 12.5% (57/400), with a higher prevalence in participants aged 21\u0026ndash;30 years (24.6%) than in those aged\u0026thinsp;\u0026le;\u0026thinsp;10 years (8.4%). The participants diagnosed with respiratory disease had a significantly greater prevalence of HBoV (20.3%) compared to those without respiratory disease (8.4%) (χ\u0026sup2;=11.69, p\u0026thinsp;=\u0026thinsp;0.0006). Fever and runny nose were the most common symptoms among HBoV-positive participants, regardless of respiratory disease status.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eHBoV is prevalent in Lagos and contributes significantly to respiratory illnesses across all age groups, with the highest burden observed in young adults. These findings underscore the need for further research on the clinical implications of HBoV and its potential for nosocomial transmission in healthcare settings.\u003c/p\u003e\u003ch2\u003eTrial registration:\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e","manuscriptTitle":"Human Bocavirus as a Contributor to Respiratory Disease in Lagos, Nigeria: A Hospital-Based Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-02-19 16:28:10","doi":"10.21203/rs.3.rs-5997893/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2e9658ec-a0ed-4a08-a7a8-9cdb26096018","owner":[],"postedDate":"February 19th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-02-19T16:28:10+00:00","versionOfRecord":[],"versionCreatedAt":"2025-02-19 16:28:10","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5997893","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5997893","identity":"rs-5997893","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}