Are viral loads in the febrile phase a predictive factor of dengue disease severity?

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Shashika Dayarathna, Heshan Kuruppu, Tehani Silva, Laksiri Gomes, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4771323/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 05 Nov, 2024 Read the published version in BMC Infectious Diseases → Version 1 posted 18 You are reading this latest preprint version Abstract Background: As many studies have shown conflicting results regarding the extent of viraemia and clinical disease severity, we sought to investigate if viraemia during early dengue illness is associated with subsequent clinical disease severity. Methods: Realtime PCR was carried out to identify the dengue virus (DENV serotype), in 362 patients, presenting within the first 4 days of illness, from 2017 to 2022, in Colombo Sri Lanka. To characterize subsequent clinical disease severity, all patients were followed throughout their illness daily and disease severity classified according to WHO 1997 and 2009 disease classification. Results: 263 patients had DF, 99 progressed to develop DHF, and 15/99 with DHF developed shock (DSS). Although the viral loads were higher in the febrile phase in patients who progressed to develop DHF than in patients with DF this was not significant (p=0.5). Significant differences were observed in viral loads in patients infected with different DENV serotypes (p=0.0009), with lowest viral loads detected in DENV2 and the highest viral loads in DENV3. Sub-analysis for association of viraemia with disease severity for each DENV serotyped was again not significant. Although those infected with DENV2 had lower viral loads, infection with DENV2 was significantly associated with a higher risk of developing DHF (p=0.011, Odds ratio 1.9; 95% CI 1.164 to 3.078). Based on the WHO 2009 disease classification, 233 had dengue with warning signs (DWW), 114 dengue without warning signs (DWoWS), and 15 had severe dengue (SD). No significant difference was observed in the viral loads between those with SD, DWW and DWoWS (p=0.27). Conclusions: Viral loads were significantly different in the febrile phase between different DENV serotypes, and do not appear to significantly associate with subsequent clinical disease severity in a large Sri Lankan cohort. Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Dengue, which was named as one of the top ten threats to global health by the WHO is the most rapidly increasing mosquito borne viral infection [ 1 ]. As it is a climate sensitive infection, due to the rise in global temperatures, it is predicted that burden of dengue is likely to further increase, resulting in potential overwhelming of the health-care systems in further areas and countries [ 2 ]. As there is no effective treatment for dengue, all patients with a suspected DENV infection are closely monitored for early detection of complications for timely interventions in the form of meticulous fluid management [ 3 ]. While most DENV infections result in asymptomatic or mild illness, some individuals develop vascular leakage resulting in pleural effusions, ascites, shock and other complications such as bleeding and organ dysfunction [ 3 ]. The reasons for occurrence of vascular leakage and other complications in some individuals are unknown, but a secondary dengue, pregnancy, presence of comorbidities such as diabetes, obesity and chronic kidney disease are known risk factors [ 4 – 6 ]. A dysfunctional innate immune response that results in an impaired antiviral immunity, with an enhanced proinflammatory response, presence of poor quality non-neutralizing antibodies and a sub-optimum T cell response are known to contribute to severe disease [ 7 , 8 ]. Although severe clinical disease manifestations occur due to an aberrant and suboptimum immune response, the dengue virus (DENV) is known to lead to induction of many inflammatory mediators and therefore, directly contributes to disease pathogenesis [ 9 ]. Therefore, targeting the DENV and inhibiting viral replication has been one of the main strategies for developing a treatment for dengue [ 10 ]. However, many studies have shown conflicting results regarding the extent of viraemia and clinical disease severity. In a recent very large study from Vietnam, it was shown that higher plasma viraemia increased the risk of severe disease, hospitalization and plasma leakage, irrespective of the infecting serotype and the immune status [ 11 ]. However, they also show that although the viral loads were highest for DENV1 and lowest with infections with DENV2, infection with DENV2 was associated with a higher risk of developing severe dengue [ 11 ]. Another study from Vietnam showed that viral loads during early illness was significantly less in those with secondary dengue, although secondary dengue is an important risk factor for severe disease. [ 12 ]. A study from Indonesia showed that DENV3 was associated with a higher risk of plasma leakage compared to other serotypes and that there was a trend towards higher viraemia in those who develop severe dengue [ 13 ]. Studies from Colombia and India showed that the viral loads had no relationship with clinical disease severity [ 14 , 15 ]. The contradictory findings in different studies could be due to different viral dynamics based on timing, different genotypes of the virus, differences in host responses based on genetic predisposition and ethnicities. As many antiviral trials for dengue failed to show efficacy so far, and as many trials are underway, it would be important to understand if viral loads during early illness associate with subsequent disease severity in different countries and in different populations. In this study, we have characterized the viral loads during early illness in patients presenting to a large tertiary care hospital in Sri Lanka, over a period of 5 years, to understand the relationship between viral loads, different DENV serotypes and clinical disease severity. Methods Patients with acute dengue infection Adult patients (n = 412) with suspected acute dengue were recruited from the National Institute of Infectious Diseases, Sri Lanka from September 2017 to September 2022 following informed written consent to the study. Blood samples were collected from each patient, during the first four days since onset of symptoms (days of illness ≤ 4 days), which was during the febrile phase. A second blood sample could only be collected from 149 patients between day 5 to 7 of illness for dengue antibody assays, as some patients did not consent to obtaining a second blood sample as they were bled several times each day for routine investigations. Any patient who had features of plasma leakage at the time of recruitment, were excluded from the study, as we wished to assess the relationship of viral loads with subsequent disease severity, including development of plasma leakage. To characterize clinical disease severity, all patients were followed throughout their illness daily, and all clinical and laboratory features were recorded. 44 patients did not require admission, while all other patients were admitted to hospital. Ultrasound scans were done in all patients at the time of admission to detect the presence of fluid leakage and repeated daily until the patient recovered, to detect the presence of any fluid leakage. If the patients showed a rise in the haematocrit, with subsequent reduction in platelet counts (these parameters were monitored on a daily basis in all patients), ultrasound scans were performed to detect pleural effusions and ascites. Determining the DENV serotype and viral loads Blood samples were centrifuged, and the obtained serum samples were aliquoted and stored at -80°C to avoid repeated freeze-thawing. Viral RNA was extracted from the serum using QIAmp Viral RNA Mini Kit (Qiagen, USA, Cat: 52906). cDNA transcription was performed with a high-capacity cDNA reverse transcription kit (Applied Biosystems, USA, cat: 4368814). Oligonucleotide primers, dual labelled probes for DEN 1 to 4 serotypes (Life Technologies, India) and TaqMan Multiplex Master Mix (Applied Biosystems, USA, Cat: 4461881) were used for the multiplex quantitative real-time PCR in ABI 7500 real time PCR system (Applied Biosystems, USA) as previously described [ 16 ]. The standard curve was generated using four gBlock fragments with known copy numbers (Integrated DNA Technologies, USA). Dengue IgM and IgG antibody assays Dengue antibody assays were performed in 149 patients, in whom a second sample could be collected between day 5 to 7 of illness, using a commercial capture-IgM and IgG Enzyme- Linked Immunosorbent Assay (ELISA) (Panbio, Australia). Results were interpreted according to the manufacturer’s instructions. According to the WHO 2011 criteria, patients with an IgM: IgG ratio of > 1.2 were classified as having primary dengue, while patients with IgM: IgG ratio of < 1.2 were categorized under secondary dengue[ 3 ]. Statistical analysis Statistical analysis was done using GraphPad Prism version 9.5.1 (Dotmatics, California, USA). As the data were not normally distributed, differences in the viral loads for different clinical disease severity and serotypes were compared using the Mann-Whitney U test (two tailed). The Kruskal-Wallis test was used to compare the viral loads between different serotypes, when more than one parameter was compared. Spearman rank order correlation coefficient was used to evaluate the correlation between variables including the association between viral loads and laboratory parameters. Results Patient characteristics The 412 adult patients were recruited on a median duration of day 3 (IQR 3 to 4 days) since onset of illness. The DENV serotype was identified in 362 (87.9%) patients and were included in the analysis. 50 patients tested negative in qPCR serotyping and therefore were excluded from the analysis. In order to determine the relationship between viral loads in the febrile phase and subsequent clinical disease severity, patients were classified as having DF or DHF, according to the WHO 1997 criteria [ 3 ]. Analysis was also carried out by classifying them as having dengue with warning signs (DWW), without warning signs (DWoWS) and with severe disease (SD) according to the WHO 2009 disease classification guidelines [ 17 ]. The clinical and laboratory characteristics of patients when classified as DF/DHF, and DWW, DWoWS and SD are shown in Table 1 and 2 . The mean age of those who were recruited to the study was 33.02 years (SD ± 13.47) and median age 29 years. 234 (56.8%) patients were in the 20- to 40-year-old age group. There was no correlation with the age and the viral loads during the febrile phase of illness (Spearman’s R=-0.07, p = 0.2067). Table 1 Clinical and laboratory features of patients who were classified as having DHF and DF based on the WHO 1997 disease classification Clinical findings DF (n = 263) N% DHF (n = 99) N% Fever 243 (92.4) 96 (97.0) Arthralgia 142 (54.0) 71 (71.7) Myalgia 137 (52.1) 64 (64.6) Flushing 13 (4.9) 7 (7.1) Rashes 2 (0.8) 2 (2.0) Itching 2 (0.8) 1 (1.0) Abdominal pain 51 (19.4) 38 (38.4) Vomiting 61 (23.2) 31 (31.3) Diarrhoea 75 (28.5) 40 (40.4) Pleural effusion 0 14 (14.1) Ascites in hepatorenal pouch 0 81 (81.8) Hepatomegaly 1 (0.4) 1 (1.0) Petechiae 2 (0.8) 1 (1.0) Ecchymoses 0 0 Epistaxis 0 2 (2.0) Haematemesis 0 0 Malena 1 (0.4) 0 Bleeding from the site of venepuncture 0 0 Vaginal bleeding 4 (1.5) 7 (7.1) Lowest platelet count /mm 3 100,000 110 (41.8) 4 (4.0) Lowest WBC count cells/µl 5000 28 (10.6) 7 (7.1) Table 2 Clinical and laboratory features of patients who were classified as having severe dengue (SD), dengue with warning signs (DWW) and dengue without warning signs (DWoWS) according to the WHO 2009 disease classification Clinical findings SD (n = 15) N% DWW (n = 233) N% DWoWS (n = 114) N% Fever 14 (93.3) 223 (95.7) 102 (89.5) Arthralgia 10 (66.7) 152 (65.2) 51 (44.7) Myalgia 9 (60.0) 143 (61.4) 41 (36.0) Flushing 1 (6.7) 15 (6.4) 4 (3.5) Rashes 1 (6.7) 3 (1.3) 0 Itching 0 3 (1.3) 0 Abdominal pain 3 (20.0) 84 (36.1) 2 (1.8) Vomiting 4 (26.7) 88 (37.8) 0 Diarrhoea 4 (26.7) 93 (39.9) 18 (15.8) Pleural effusion 0 14 (6.0) 0 Ascites in hepatorenal pouch 8 (53.3) 73 (31.3) 0 Hepatomegaly 0 2 (0.9) 0 Petechiae 0 2 (0.9) 2 (1.8) Ecchymoses 0 0 0 Epistaxis 0 2 (0.9) 0 Haematemesis 0 0 0 Malena 0 1 (0.4) 0 Bleeding from the site of venepuncture 0 0 0 Vaginal bleeding 2 (13.3) 7 (3.0) 2 (1.8) Lowest platelet count /mm 3 100,000 3 (20.0) 30 (12.9) 81 (71.1) Lowest WBC count cells/µl 5000 3 (20.0) 15 (6.4) 17 (14.9) According to the WHO 1997 guidelines, those who had features of plasma leakage (pleural effusions or ascites along with platelet counts 20% were classified as having DHF. None of the patients had pericardial effusions. As daily ultrasound scans were done in all patients, to determine the presence of fluid leakage and when they developed fluid leakage, as per the National Management guidelines, serum albumin levels were not done [ 18 ]. Patients with DHF, who had a narrowing pulse pressure ≤ 20 were classified as having shock. Accordingly of the 362 PCR positive patients, 263 patients had DF, 99 progressed to develop DHF and of them 15 developed shock (DSS). Among the 362 qPCR positive patients, 231 (63.8%) were of males and 131 (36.2%) were of females, and 63 (27.3%) of males developed DHF vs 36 (27.5%) females. Based on the WHO 2009 disease classification, 233 had DWW, 114 DWoWS, and 15 had SD. Viral loads at febrile phase and relationship with clinical disease severity based on WHO 1997 disease classification 214 (59.1%) of patients were infected with DENV2, 91 (25.1%) with DENV1 and 54 (14.9%) with DENV3, while DENV4 was not detected in any of the patients. Three patients were found to be infected with two DENV serotypes: DENV1 and DENV2 (n = 2) and DENV2 and DENV3 (n = 1) and were not included in the analysis. Although the viral loads were higher in the febrile phase in patients who progressed to develop DHF (median 3.80x10 4 copies/µl, IQR: 1.36x10 6 copies/µl to 1.24x10 3 copies/µl) than in patients with DF (median 2.13x10 4 copies/µl, IQR: 1.58x10 6 copies/µl to 2.64x10 2 copies/µl), this was not significant (p = 0.50) (Fig. 1 A). There were no significant differences in viral loads during the febrile phase in those who progressed to develop DSS vs DHF and DF (p = 0.79). However, significant differences were observed in viral loads in patients infected with different DENV serotypes (p = 0.0009) (Fig. 1 B). The lowest viral loads were detected in those infected with DENV2, while the highest viral loads were observed in those infected with DENV3. Although those infected with DENV2 had lower viral loads, infection with DENV2 was significantly associated with a higher risk of developing DHF (p = 0.0106, Odds ratio 1.9; 95% CI 1.164 to 3.078), when compared to other serotypes. Significant differences were seen in the febrile phase in viral loads of patients infected with different viral serotypes, who subsequently progressed to develop DHF (p = 0.0331), (Fig. 1 C) or DF (p = 0.004), (Fig. 1 D). Although not significant, those who were infected with either DENV2 or DENV3 and subsequently progressed to DHF, had higher viral loads in the febrile phase than those who had DF. In contrast, in those infected with DENV1, those who progressed to DHF, had lower viral loads in the febrile phase than those who had DF. Due to the differences in the viral loads seen between different serotypes, we carried out a sub-analysis to see if viral loads were associated with disease severity for each DENV serotype. There were no differences in the viral loads in those with DF and DHF in those infected with DENV1 (p = 0.22), DENV2 (p = 0.21) or DENV3 (p = 0.25). Although a second blood sample was obtained in 149 of the initial cohort of patients, as the virus serotype could only be determined in 147/149 patients, we only included this cohort in the analysis of primary and secondary dengue. Accordingly, 49/147 (33.33%) had -primary dengue and 98/147 (66.67%) had secondary dengue. There was no significant difference between the viral loads of those with primary and secondary dengue during early illness (p = 0.8609) (Fig. 2 ). There was no difference between the viral loads in primary and secondary dengue in those infected with different DENV serotypes. However, the number of patients infected with DENV1 (n = 32) and DENV3 (n = 23) who were included in the analysis was too small for a meaningful analysis. Association of viral loads with laboratory parameters The viral loads in the febrile phase inversely correlated with the lowest platelet counts of those who progressed to develop DHF (Spearman’s R= -0.2393, p = 0.0.0182) (Fig. 3 A), but not with their lowest leucocyte counts (Spearman’s R= -0.0012, p = 0.9908). No such association was seen in those with DF for platelet counts (Spearman’s R = 0.0118, p = 0.8508) (Fig. 3 B) or leucocyte counts (Spearman’s R= -0.0410, p = 0.5111). Liver enzymes (AST and ALT) could only be done in 159 patients, as these investigations were not routinely done throughout the years in which the samples were collected. There was no correlation seen with the viral loads and ALT (Spearman’s R= -0.0125, p = 0.8766) (Fig. 3 C) or AST (Spearman’s R= -0.0370, p = 0.6440) (Fig. 3 D). However, a significant difference was observed in AST (p = 0.0066) and ALT (p = 0.0008) levels between those who developed DHF and DF. Viral loads and relationship with clinical disease severity at the time of recruitment based on WHO 2009 criteria No significant difference was observed in the viral loads between those with SD, DWW and DWoWS (p = 0.2722) (Fig. 4 A). However, significant differences were observed with the viral loads for different DENV serotypes in DWW (p = 0.0028) (Fig. 4 B, C and D). Overall, the viral loads were lower with DENV2, compared to viral loads due to DENV1 and DENV3 in patients of all clinical disease categories. Discussion In this study we have assessed the viral loads during early illness, during a period of five years in a large cohort of patients from Sri Lanka, who were followed up daily throughout the course of their illness, to determine their clinical disease severity. We used both the WHO 1997 and WHO 2009 to characterize disease severity and to determine if viral loads were predictive of disease severity, as different countries use different disease severity classification criteria. Using the WHO 1997 dengue disease classification we found that there was a trend towards viral loads being higher in those who progressed to DHF when infected with DENV2 and DENV3, although such a trend was not seen when the WHO 2009 dengue disease classification was used. Therefore, the viral loads did not appear to associate with subsequent disease outcomes, irrespective of the disease classification used. However, previous studies using different clinical disease severity classifications have shown that viral loads at presentation do in fact associate with subsequent disease severity in children with low levels if DENV antibody titres [ 19 ]. A large study in Vietnam too showed that higher viral loads in the febrile phase was associated with increased risk of hospitalization and plasma leakage, although the risk was modest [ 11 ]. Although we did not find viraemia levels associate with disease severity, the viral loads did inversely correlate with the extent of thrombocytopenia, as shown in previous studies [ 20 ]. We found significant differences in the viral loads in patients infected with different serotypes, with viral loads being highest with DENV3 and lowest with DENV2. As reported previously from a large study in Vietnam, and many other studies, we found that DENV2 was associated with lower viral loads, but with a higher risk of developing DHF [ 11 , 21 ]. Higher viral loads for DENV1, followed by DENV3 has been shown in two previous studies from Vietnam [ 11 , 12 ] further showing that the kinetics of viral loads significantly differ between the DENV serotypes during early illness. As certain genotypes of the DENV appears to associate with increased disease severity (cosmological strain of DENV2) and with certain neurological complications, it would be important to further evaluate the differences in viral loads and kinetics for these different DENV genotypes [ 22 , 23 ]. Furthermore, these differences in the viral loads and NS1 antigen levels of different DENV serotypes, have significant implications when evaluating point-of care diagnostics and antiviral drugs for dengue. Therefore, in such evaluations, it would be important to carry out studies in them across different geographical regions and populations, which may have different circulating DENV serotypes and genotypes. Although many studies do not show a statistically significant association with viral loads and clinical disease severity, many have shown a trend towards increased disease severity when infected with DENV2 [ 11 ], which had the lowest viral loads of the DENV serotypes. It is possibly due to greater immune evasive capacity by DENV2 infection, as strains of DENV2 have shown an enhanced ability to inhibit type 1 interferon signaling compared to other DENV serotypes [ 24 ]. Apart from these variations seen between DENV serotypes and particular genotypes, there is a huge individual variation between viral loads. Our data along with many other studies show several log differences of viral loads for different DENV serotypes in patients with varying disease severity during the febrile phase. Many factors such as the initial viral inoculum, the incubation period, previous immunity, and presence of comorbid illnesses have shown to affect viral loads [ 19 , 25 ]. It was shown that the incubation period was shorter in those with secondary dengue compared to primary infection, supporting the role of antibody dependent enhancement in disease pathogenesis [ 25 , 26 ]. Although we analyzed the differences in viral loads in the febrile phase in those with primary and secondary dengue, the sample size was small and only a few patients were infected with DENV1 and DENV3, to include in analysis. However, our results were similar to the large study done in Vietnam comparing viral loads in relation to immune status, which showed no difference in early illness [ 11 ]. A previous study done in Vietnam and in Singapore for evaluation of the antiviral effect of celgosivir showed that the viral loads were not in fact different in the early phase, but those with secondary dengue, cleared the plasma viraemia earlier than those with primary dengue [ 12 , 27 ]. Therefore, although patients with secondary dengue have shorter incubation periods and possibly higher viral infection in FcγR bearing cells, due to antibody dependent enhancement, this is not reflected in the viraemia seen in serum. This possibly suggests that the viral loads and viral kinetics seen in serum may not necessarily reflect the viraemia within immune cells and tissues. Conclusions In summary, although the degree of viraemia leads to severe disease, there is an important role played by the host-immune response to which could lead to resolution of infection or lead to immunopathogenesis. While use of antivirals would be an important treatment strategy for dengue, drugs that target certain immune mediators, such as leukotrienes, chymase, tryptase, platelet activating factor, growth factors, cytokines and other lipid mediators would be of potential benefit. Declarations Ethics approval and consent to participate Ethical approval was obtained from the Ethics Review Committee of the Faculty of Medical Sciences, University of Sri Jayewardenepura (58/19). Consent for publication Not applicable Availability of data and materials All data is available in the manuscript, figures and the supporting files Competing interests The authors have no competing interests. Funding We are grateful to the NIH, USA (grant number 5U01AI151788-02), Accelerating Higher Education Expansion and Development (AHEAD) Operation of the Ministry of Higher Education funded by the World Bank, and the UK Medical Research Council. Authors' contributions Conceptualization: GNM, CJ, GSO Data curation: HK, TS, NLAS, AW Laboratory investigations and methodology: SD, HK, TS, LG, DA, STR Data analysis: SD, GNM Project administration and supervision: GNM, CJ, AW Funding acquisition: GNM, CJ, GSO Writing the initial draft: SD, GNM Review and editing the final draft: GSO, GNM Acknowledgements None References WHO. Ten threats to global health in 2019. In.: World Health Organization; 2019. Colon-Gonzalez FJ, Sewe MO, Tompkins AM, Sjodin H, Casallas A, Rocklov J, et al. Projecting the risk of mosquito-borne diseases in a warmer and more populated world: a multi-model, multi-scenario intercomparison modelling study. Lancet Planet Health. 2021;5(7):e404–14. 10.1016/S2542-5196(21)00132-7 . WHO. Comprehensive guidelines for prevention and control of dengue fever and dengue haemorrhagic fever. SEARO Technical Publication Series. Volume 60. New Delhi, India: World Health Organization;: SEARO; 2011. 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Cite Share Download PDF Status: Published Journal Publication published 05 Nov, 2024 Read the published version in BMC Infectious Diseases → Version 1 posted Editorial decision: Revision requested 17 Sep, 2024 Reviews received at journal 16 Sep, 2024 Reviews received at journal 09 Sep, 2024 Reviewers agreed at journal 08 Sep, 2024 Reviewers agreed at journal 06 Sep, 2024 Reviews received at journal 05 Sep, 2024 Reviewers agreed at journal 30 Aug, 2024 Reviewers agreed at journal 30 Aug, 2024 Reviews received at journal 20 Aug, 2024 Reviewers agreed at journal 12 Aug, 2024 Reviewers agreed at journal 12 Aug, 2024 Reviewers agreed at journal 11 Aug, 2024 Reviewers agreed at journal 09 Aug, 2024 Reviewers invited by journal 08 Aug, 2024 Editor invited by journal 30 Jul, 2024 Editor assigned by journal 23 Jul, 2024 Submission checks completed at journal 23 Jul, 2024 First submitted to journal 20 Jul, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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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-4771323","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":341887269,"identity":"08d8f746-6e4d-411c-bc5e-97bcf1309fae","order_by":0,"name":"Shashika Dayarathna","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Shashika","middleName":"","lastName":"Dayarathna","suffix":""},{"id":341887270,"identity":"382bbd3b-0ff7-4c76-bd13-993b21ce4121","order_by":1,"name":"Heshan Kuruppu","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Heshan","middleName":"","lastName":"Kuruppu","suffix":""},{"id":341887271,"identity":"a077c586-e90c-4bcb-b679-dab98e386df3","order_by":2,"name":"Tehani Silva","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Tehani","middleName":"","lastName":"Silva","suffix":""},{"id":341887273,"identity":"e9312789-7057-4e8d-a7a6-a67bfd27b688","order_by":3,"name":"Laksiri Gomes","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Laksiri","middleName":"","lastName":"Gomes","suffix":""},{"id":341887275,"identity":"1d458c06-d3f4-4a27-ae8c-953dd59dda76","order_by":4,"name":"N. L. Ajantha Shyamali","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"N.","middleName":"L. Ajantha","lastName":"Shyamali","suffix":""},{"id":341887276,"identity":"66897acf-65db-461f-b999-a30e8f65b9fc","order_by":5,"name":"Chandima Jeewandara","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Chandima","middleName":"","lastName":"Jeewandara","suffix":""},{"id":341887279,"identity":"806bde14-8302-4b7d-9fbd-41e8d2ab6fa9","order_by":6,"name":"Dinuka Ariyaratne","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Dinuka","middleName":"","lastName":"Ariyaratne","suffix":""},{"id":341887281,"identity":"cfcb2156-d2ab-44d7-8cf9-fa2430bcdab5","order_by":7,"name":"Shyrar Tanussiya Ramu","email":"","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":false,"prefix":"","firstName":"Shyrar","middleName":"Tanussiya","lastName":"Ramu","suffix":""},{"id":341887283,"identity":"79f50548-9488-4fea-b1b7-57c6a245cc15","order_by":8,"name":"Ananda Wijewickrama","email":"","orcid":"","institution":"National Institute of Infectious Diseases","correspondingAuthor":false,"prefix":"","firstName":"Ananda","middleName":"","lastName":"Wijewickrama","suffix":""},{"id":341887286,"identity":"f14534d1-0465-40a3-84e3-54b2e5e26c79","order_by":9,"name":"Graham S. Ogg","email":"","orcid":"","institution":"University of Oxford","correspondingAuthor":false,"prefix":"","firstName":"Graham","middleName":"S.","lastName":"Ogg","suffix":""},{"id":341887287,"identity":"1f88db88-cf02-44dd-b4dd-83bfe5c00dcd","order_by":10,"name":"Gathsaurie Neelika Malavige","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABQklEQVRIie2RMUvDQBTHXwi+LhezXoj0vsIrgUKpuPo1GgJ2tCCUQgUzxSU0q7tfwMk5cpAupV1bbmkpdOogCCWgiG0sUhIRR8H8hrt37/Hjf8cBlJT8TfBg7WSFNt8fM6hg6IcKZYVOv1IOx8h/UsT5JFmk1/LyuOIfPaR05g7M+6Tf6T6CyVvacwrSySm1kVdxWCIbAYtxFpLnBnx1oe7GCqww1q0QZD2v+B7agJKQt3DKSHeQj+rKCBTQ0AcbQJ7mlWiJVvq+VcQcZ290s1Umm6tMkaC/fqMI7iE3gl0KoGIkq2iGqO9TcJeSvxjxZd02Bm1C5gbqhIZV5OjYbKyYFT4FjZDa+eeLyF1Z6aZJ4lYms3Wvz0QkFy+sq6om9+Q07TVrfi4l/iq1/Yi3so19doofKfxCy4wLrZKSkpL/zQdf5mY6LLaAUQAAAABJRU5ErkJggg==","orcid":"","institution":"University of Sri Jayewardenepura","correspondingAuthor":true,"prefix":"","firstName":"Gathsaurie","middleName":"Neelika","lastName":"Malavige","suffix":""}],"badges":[],"createdAt":"2024-07-20 05:21:31","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4771323/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4771323/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12879-024-10152-2","type":"published","date":"2024-11-05T15:57:25+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":63299775,"identity":"4742e8a4-9135-42e9-9bd9-d6b24dcc57a1","added_by":"auto","created_at":"2024-08-26 15:57:06","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":227834,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eViral loads in patients with varying clinical disease severity and infected with different DENV serotypes\u003c/strong\u003e. Viral loads in serum samples were measured by qPCR in those with DF (n=261) and in those who progressed to DHF (n=98), during the febrile phase (A). Viral loads were compared in patients infected with different DENV virus serotypes, DENV1 (n=91), DENV2 (n=214) and DENV3 (n=54) (B) in those with DHF (C) and DF (D) infected with different virus serotypes. The Mann-Whitney test was used to compare the differences in viral loads between those with DF and DHF, while Kruskal-Wallis test was performed to compare the differences in viral loads in those infected different serotypes. All tests were two sided. Data are presented as median values +/- interquartile ranges as appropriate.\u003c/p\u003e","description":"","filename":"Fig1new.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4771323/v1/77fb97430d3f435894051a4b.jpg"},{"id":63299934,"identity":"361d507c-e398-4837-9a08-6892b495dd5c","added_by":"auto","created_at":"2024-08-26 16:05:08","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1381145,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eViral loads in patients with primary and secondary dengue. \u003c/strong\u003eViral loads in serum samples were measured by qPCR in those primary (n=48) and secondary (n=96) dengue. They were also compared in those with primary and secondary dengue, infected with different DENV serotypes. The Mann-Whitney test was used to compare the differences in viral loads between those with primary and secondary dengue. All tests were two sided. Data are presented as median values +/- interquartile ranges as appropriate.\u003c/p\u003e","description":"","filename":"Fig2new.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4771323/v1/f1e5619dfcd676c6dbf46d5d.jpg"},{"id":63299776,"identity":"3cd68cf1-1793-4c2e-a6ae-25fad849a177","added_by":"auto","created_at":"2024-08-26 15:57:06","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":233927,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eAssociation between the viral loads and the laboratory parameters in patients with varying severity of acute dengue.\u003c/strong\u003e The correlation between the viral loads and the lowest platelet counts detected throughout the course of illness of the patients in DHF (n=98) (A), and DF (n=261) (B) were assessed. Data of 3 patients who had co-infection are not included in the analysis. Further, the viral loads and ALT levels (C) and AST levels (D) were measured in patients with DF and DHF patients (n=179). Spearman rank order correlation coefficient was used to evaluate the correlation between the viral loads and AST and ALT. All tests were two sided.\u003c/p\u003e","description":"","filename":"Fig3new.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4771323/v1/fa789e70601398921e404d64.jpg"},{"id":63299933,"identity":"6a81889e-92e9-49b7-8233-17dc4cb2ef76","added_by":"auto","created_at":"2024-08-26 16:05:07","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":187093,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eViral loads in patients with varying clinical disease severity (classified according to the WHO 2009 disease classification) and infected with different DENV serotypes. \u003c/strong\u003eViral loads between patients with SD (n=15), DWW (n=231) and DWoWS (n=113) were compared (A). Data of 3 patients who had co-infection are not shown. Viral loads of different serotypes in patients with SD (n=15) (B), in those with DWW (n=231) (C) and in those with DWoWS (n=113) (D) were also compared. Kruskal-Wallis test was performed to compare the viral loads among the three groups of varying severity and the infected serotype. All tests were two sided. Data are presented as median values +/- interquartile ranges as appropriate and the p value is indicated.\u003c/p\u003e","description":"","filename":"Fig4new.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4771323/v1/7a1b8d6441f23b7c7db7f59f.jpg"},{"id":68749881,"identity":"8cd66f27-d13a-4d22-a542-e06f5655d2bb","added_by":"auto","created_at":"2024-11-11 16:07:12","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2892265,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4771323/v1/211461fd-1cb5-435c-a8c8-0dc5995596a2.pdf"},{"id":63299774,"identity":"551dc4c6-604e-4954-ba23-091a6ded378f","added_by":"auto","created_at":"2024-08-26 15:57:06","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":75315,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSupplementary data\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRaw data set that was used to generate figures and all results in the manuscript.\u003c/p\u003e","description":"","filename":"Supplementarydata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-4771323/v1/a550387134ab4b29f24aa81c.xlsx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Are viral loads in the febrile phase a predictive factor of dengue disease severity?","fulltext":[{"header":"Background","content":"\u003cp\u003eDengue, which was named as one of the top ten threats to global health by the WHO is the most rapidly increasing mosquito borne viral infection [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. As it is a climate sensitive infection, due to the rise in global temperatures, it is predicted that burden of dengue is likely to further increase, resulting in potential overwhelming of the health-care systems in further areas and countries [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. As there is no effective treatment for dengue, all patients with a suspected DENV infection are closely monitored for early detection of complications for timely interventions in the form of meticulous fluid management [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhile most DENV infections result in asymptomatic or mild illness, some individuals develop vascular leakage resulting in pleural effusions, ascites, shock and other complications such as bleeding and organ dysfunction [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The reasons for occurrence of vascular leakage and other complications in some individuals are unknown, but a secondary dengue, pregnancy, presence of comorbidities such as diabetes, obesity and chronic kidney disease are known risk factors [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. A dysfunctional innate immune response that results in an impaired antiviral immunity, with an enhanced proinflammatory response, presence of poor quality non-neutralizing antibodies and a sub-optimum T cell response are known to contribute to severe disease [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAlthough severe clinical disease manifestations occur due to an aberrant and suboptimum immune response, the dengue virus (DENV) is known to lead to induction of many inflammatory mediators and therefore, directly contributes to disease pathogenesis [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Therefore, targeting the DENV and inhibiting viral replication has been one of the main strategies for developing a treatment for dengue [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. However, many studies have shown conflicting results regarding the extent of viraemia and clinical disease severity. In a recent very large study from Vietnam, it was shown that higher plasma viraemia increased the risk of severe disease, hospitalization and plasma leakage, irrespective of the infecting serotype and the immune status [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. However, they also show that although the viral loads were highest for DENV1 and lowest with infections with DENV2, infection with DENV2 was associated with a higher risk of developing severe dengue [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Another study from Vietnam showed that viral loads during early illness was significantly less in those with secondary dengue, although secondary dengue is an important risk factor for severe disease. [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. A study from Indonesia showed that DENV3 was associated with a higher risk of plasma leakage compared to other serotypes and that there was a trend towards higher viraemia in those who develop severe dengue [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Studies from Colombia and India showed that the viral loads had no relationship with clinical disease severity [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe contradictory findings in different studies could be due to different viral dynamics based on timing, different genotypes of the virus, differences in host responses based on genetic predisposition and ethnicities. As many antiviral trials for dengue failed to show efficacy so far, and as many trials are underway, it would be important to understand if viral loads during early illness associate with subsequent disease severity in different countries and in different populations. In this study, we have characterized the viral loads during early illness in patients presenting to a large tertiary care hospital in Sri Lanka, over a period of 5 years, to understand the relationship between viral loads, different DENV serotypes and clinical disease severity.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients with acute dengue infection\u003c/h2\u003e \u003cp\u003eAdult patients (n\u0026thinsp;=\u0026thinsp;412) with suspected acute dengue were recruited from the National Institute of Infectious Diseases, Sri Lanka from September 2017 to September 2022 following informed written consent to the study. Blood samples were collected from each patient, during the first four days since onset of symptoms (days of illness\u0026thinsp;\u0026le;\u0026thinsp;4 days), which was during the febrile phase. A second blood sample could only be collected from 149 patients between day 5 to 7 of illness for dengue antibody assays, as some patients did not consent to obtaining a second blood sample as they were bled several times each day for routine investigations. Any patient who had features of plasma leakage at the time of recruitment, were excluded from the study, as we wished to assess the relationship of viral loads with subsequent disease severity, including development of plasma leakage. To characterize clinical disease severity, all patients were followed throughout their illness daily, and all clinical and laboratory features were recorded. 44 patients did not require admission, while all other patients were admitted to hospital. Ultrasound scans were done in all patients at the time of admission to detect the presence of fluid leakage and repeated daily until the patient recovered, to detect the presence of any fluid leakage. If the patients showed a rise in the haematocrit, with subsequent reduction in platelet counts (these parameters were monitored on a daily basis in all patients), ultrasound scans were performed to detect pleural effusions and ascites.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eDetermining the DENV serotype and viral loads\u003c/h2\u003e \u003cp\u003eBlood samples were centrifuged, and the obtained serum samples were aliquoted and stored at -80\u0026deg;C to avoid repeated freeze-thawing. Viral RNA was extracted from the serum using QIAmp Viral RNA Mini Kit (Qiagen, USA, Cat: 52906). cDNA transcription was performed with a high-capacity cDNA reverse transcription kit (Applied Biosystems, USA, cat: 4368814). Oligonucleotide primers, dual labelled probes for DEN 1 to 4 serotypes (Life Technologies, India) and TaqMan Multiplex Master Mix (Applied Biosystems, USA, Cat: 4461881) were used for the multiplex quantitative real-time PCR in ABI 7500 real time PCR system (Applied Biosystems, USA) as previously described [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The standard curve was generated using four gBlock fragments with known copy numbers (Integrated DNA Technologies, USA).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eDengue IgM and IgG antibody assays\u003c/h2\u003e \u003cp\u003eDengue antibody assays were performed in 149 patients, in whom a second sample could be collected between day 5 to 7 of illness, using a commercial capture-IgM and IgG Enzyme- Linked Immunosorbent Assay (ELISA) (Panbio, Australia). Results were interpreted according to the manufacturer\u0026rsquo;s instructions. According to the WHO 2011 criteria, patients with an IgM: IgG ratio of \u0026gt;\u0026thinsp;1.2 were classified as having primary dengue, while patients with IgM: IgG ratio of \u0026lt;\u0026thinsp;1.2 were categorized under secondary dengue[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eStatistical analysis was done using GraphPad Prism version 9.5.1 (Dotmatics, California, USA). As the data were not normally distributed, differences in the viral loads for different clinical disease severity and serotypes were compared using the Mann-Whitney U test (two tailed). The Kruskal-Wallis test was used to compare the viral loads between different serotypes, when more than one parameter was compared. Spearman rank order correlation coefficient was used to evaluate the correlation between variables including the association between viral loads and laboratory parameters.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003ePatient characteristics\u003c/h2\u003e \u003cp\u003eThe 412 adult patients were recruited on a median duration of day 3 (IQR 3 to 4 days) since onset of illness. The DENV serotype was identified in 362 (87.9%) patients and were included in the analysis. 50 patients tested negative in qPCR serotyping and therefore were excluded from the analysis. In order to determine the relationship between viral loads in the febrile phase and subsequent clinical disease severity, patients were classified as having DF or DHF, according to the WHO 1997 criteria [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Analysis was also carried out by classifying them as having dengue with warning signs (DWW), without warning signs (DWoWS) and with severe disease (SD) according to the WHO 2009 disease classification guidelines [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The clinical and laboratory characteristics of patients when classified as DF/DHF, and DWW, DWoWS and SD are shown in Table \u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The mean age of those who were recruited to the study was 33.02 years (SD\u0026thinsp;\u0026plusmn;\u0026thinsp;13.47) and median age 29 years. 234 (56.8%) patients were in the 20- to 40-year-old age group. There was no correlation with the age and the viral loads during the febrile phase of illness (Spearman\u0026rsquo;s R=-0.07, p\u0026thinsp;=\u0026thinsp;0.2067).\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\u003eClinical and laboratory features of patients who were classified as having DHF and DF based on the WHO 1997 disease classification\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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClinical findings\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eDF (n\u0026thinsp;=\u0026thinsp;263)\u003c/p\u003e \u003cp\u003eN%\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eDHF (n\u0026thinsp;=\u0026thinsp;99)\u003c/p\u003e \u003cp\u003eN%\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFever\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e243\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(92.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(97.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eArthralgia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e142\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(54.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(71.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMyalgia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e137\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(52.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(64.6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFlushing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(4.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(7.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRashes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(0.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(2.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eItching\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(0.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(1.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbdominal pain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(19.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(38.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVomiting\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(23.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(31.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiarrhoea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(28.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(40.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePleural effusion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(14.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAscites in hepatorenal pouch\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(81.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHepatomegaly\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(0.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(1.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePetechiae\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(0.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(1.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEcchymoses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEpistaxis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(2.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHaematemesis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMalena\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(0.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBleeding from the site of venepuncture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVaginal bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(1.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(7.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLowest platelet count /mm\u003c/b\u003e\u003csup\u003e\u003cb\u003e3\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;20,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(3.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(51.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e20,000 to 50,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(19.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(35.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50,000 to 100,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(35.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(8.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;100,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e110\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(41.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(4.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLowest WBC count cells/\u0026micro;l\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;2000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(14.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(15.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2000 to 5000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e195\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(74.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(76.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;5000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(10.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(7.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\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\u003eClinical and laboratory features of patients who were classified as having severe dengue (SD), dengue with warning signs (DWW) and dengue without warning signs (DWoWS) according to the WHO 2009 disease classification\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\u003eClinical findings\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eSD (n\u0026thinsp;=\u0026thinsp;15)\u003c/p\u003e \u003cp\u003eN%\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eDWW (n\u0026thinsp;=\u0026thinsp;233)\u003c/p\u003e \u003cp\u003eN%\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eDWoWS (n\u0026thinsp;=\u0026thinsp;114)\u003c/p\u003e \u003cp\u003eN%\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFever\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(93.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e223\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(95.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e102\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(89.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eArthralgia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(66.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e152\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(65.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(44.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMyalgia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(60.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e143\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(61.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(36.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFlushing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(6.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(6.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(3.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRashes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(6.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(1.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eItching\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(1.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbdominal pain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(36.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(1.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVomiting\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(26.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(37.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDiarrhoea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(26.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(39.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(15.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePleural effusion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(6.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAscites in hepatorenal pouch\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(53.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(31.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHepatomegaly\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(0.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePetechiae\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(0.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(1.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEcchymoses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEpistaxis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(0.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHaematemesis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMalena\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(0.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBleeding from the site of venepuncture\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVaginal bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(13.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(3.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(1.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLowest platelet count /mm\u003c/b\u003e\u003csup\u003e\u003cb\u003e3\u003c/b\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;20,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(46.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(22.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e20,000 to 50,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(35.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e50,000 to 100,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(6.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(29.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(26.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;100,000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(12.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(71.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLowest WBC count cells/\u0026micro;l\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;2000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(15.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(12.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2000 to 5000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(53.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e182\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(78.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(71.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;5000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e(20.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e(6.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e(14.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAccording to the WHO 1997 guidelines, those who had features of plasma leakage (pleural effusions or ascites along with platelet counts\u0026thinsp;\u0026lt;\u0026thinsp;100,000 cells/mm\u003csup\u003e3\u003c/sup\u003e or a rise in haematocrit of \u0026gt;\u0026thinsp;20% were classified as having DHF. None of the patients had pericardial effusions. As daily ultrasound scans were done in all patients, to determine the presence of fluid leakage and when they developed fluid leakage, as per the National Management guidelines, serum albumin levels were not done [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Patients with DHF, who had a narrowing pulse pressure\u0026thinsp;\u0026le;\u0026thinsp;20 were classified as having shock. Accordingly of the 362 PCR positive patients, 263 patients had DF, 99 progressed to develop DHF and of them 15 developed shock (DSS). Among the 362 qPCR positive patients, 231 (63.8%) were of males and 131 (36.2%) were of females, and 63 (27.3%) of males developed DHF vs 36 (27.5%) females. Based on the WHO 2009 disease classification, 233 had DWW, 114 DWoWS, and 15 had SD.\u003c/p\u003e \u003cp\u003e \u003cb\u003eViral loads at febrile phase and relationship with clinical disease severity based on WHO 1997 disease classification\u003c/b\u003e \u003c/p\u003e \u003cp\u003e214 (59.1%) of patients were infected with DENV2, 91 (25.1%) with DENV1 and 54 (14.9%) with DENV3, while DENV4 was not detected in any of the patients. Three patients were found to be infected with two DENV serotypes: DENV1 and DENV2 (n\u0026thinsp;=\u0026thinsp;2) and DENV2 and DENV3 (n\u0026thinsp;=\u0026thinsp;1) and were not included in the analysis. Although the viral loads were higher in the febrile phase in patients who progressed to develop DHF (median 3.80x10\u003csup\u003e4\u003c/sup\u003e copies/\u0026micro;l, IQR: 1.36x10\u003csup\u003e6\u003c/sup\u003e copies/\u0026micro;l to 1.24x10\u003csup\u003e3\u003c/sup\u003e copies/\u0026micro;l) than in patients with DF (median 2.13x10\u003csup\u003e4\u003c/sup\u003e copies/\u0026micro;l, IQR: 1.58x10\u003csup\u003e6\u003c/sup\u003e copies/\u0026micro;l to 2.64x10\u003csup\u003e2\u003c/sup\u003e copies/\u0026micro;l), this was not significant (p\u0026thinsp;=\u0026thinsp;0.50) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA). There were no significant differences in viral loads during the febrile phase in those who progressed to develop DSS vs DHF and DF (p\u0026thinsp;=\u0026thinsp;0.79).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eHowever, significant differences were observed in viral loads in patients infected with different DENV serotypes (p\u0026thinsp;=\u0026thinsp;0.0009) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB). The lowest viral loads were detected in those infected with DENV2, while the highest viral loads were observed in those infected with DENV3. Although those infected with DENV2 had lower viral loads, infection with DENV2 was significantly associated with a higher risk of developing DHF (p\u0026thinsp;=\u0026thinsp;0.0106, Odds ratio 1.9; 95% CI 1.164 to 3.078), when compared to other serotypes.\u003c/p\u003e \u003cp\u003eSignificant differences were seen in the febrile phase in viral loads of patients infected with different viral serotypes, who subsequently progressed to develop DHF (p\u0026thinsp;=\u0026thinsp;0.0331), (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC) or DF (p\u0026thinsp;=\u0026thinsp;0.004), (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD). Although not significant, those who were infected with either DENV2 or DENV3 and subsequently progressed to DHF, had higher viral loads in the febrile phase than those who had DF. In contrast, in those infected with DENV1, those who progressed to DHF, had lower viral loads in the febrile phase than those who had DF. Due to the differences in the viral loads seen between different serotypes, we carried out a sub-analysis to see if viral loads were associated with disease severity for each DENV serotype. There were no differences in the viral loads in those with DF and DHF in those infected with DENV1 (p\u0026thinsp;=\u0026thinsp;0.22), DENV2 (p\u0026thinsp;=\u0026thinsp;0.21) or DENV3 (p\u0026thinsp;=\u0026thinsp;0.25).\u003c/p\u003e \u003cp\u003eAlthough a second blood sample was obtained in 149 of the initial cohort of patients, as the virus serotype could only be determined in 147/149 patients, we only included this cohort in the analysis of primary and secondary dengue. Accordingly, 49/147 (33.33%) had -primary dengue and 98/147 (66.67%) had secondary dengue. There was no significant difference between the viral loads of those with primary and secondary dengue during early illness (p\u0026thinsp;=\u0026thinsp;0.8609) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). There was no difference between the viral loads in primary and secondary dengue in those infected with different DENV serotypes. However, the number of patients infected with DENV1 (n\u0026thinsp;=\u0026thinsp;32) and DENV3 (n\u0026thinsp;=\u0026thinsp;23) who were included in the analysis was too small for a meaningful analysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eAssociation of viral loads with laboratory parameters\u003c/h2\u003e \u003cp\u003eThe viral loads in the febrile phase inversely correlated with the lowest platelet counts of those who progressed to develop DHF (Spearman\u0026rsquo;s R= -0.2393, p\u0026thinsp;=\u0026thinsp;0.0.0182) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA), but not with their lowest leucocyte counts (Spearman\u0026rsquo;s R= -0.0012, p\u0026thinsp;=\u0026thinsp;0.9908). No such association was seen in those with DF for platelet counts (Spearman\u0026rsquo;s R\u0026thinsp;=\u0026thinsp;0.0118, p\u0026thinsp;=\u0026thinsp;0.8508) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eB) or leucocyte counts (Spearman\u0026rsquo;s R= -0.0410, p\u0026thinsp;=\u0026thinsp;0.5111). Liver enzymes (AST and ALT) could only be done in 159 patients, as these investigations were not routinely done throughout the years in which the samples were collected. There was no correlation seen with the viral loads and ALT (Spearman\u0026rsquo;s R= -0.0125, p\u0026thinsp;=\u0026thinsp;0.8766) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC) or AST (Spearman\u0026rsquo;s R= -0.0370, p\u0026thinsp;=\u0026thinsp;0.6440) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eD). However, a significant difference was observed in AST (p\u0026thinsp;=\u0026thinsp;0.0066) and ALT (p\u0026thinsp;=\u0026thinsp;0.0008) levels between those who developed DHF and DF.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eViral loads and relationship with clinical disease severity at the time of recruitment based on WHO 2009 criteria\u003c/b\u003e \u003c/p\u003e \u003cp\u003eNo significant difference was observed in the viral loads between those with SD, DWW and DWoWS (p\u0026thinsp;=\u0026thinsp;0.2722) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA). However, significant differences were observed with the viral loads for different DENV serotypes in DWW (p\u0026thinsp;=\u0026thinsp;0.0028) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB, C and D). Overall, the viral loads were lower with DENV2, compared to viral loads due to DENV1 and DENV3 in patients of all clinical disease categories.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study we have assessed the viral loads during early illness, during a period of five years in a large cohort of patients from Sri Lanka, who were followed up daily throughout the course of their illness, to determine their clinical disease severity. We used both the WHO 1997 and WHO 2009 to characterize disease severity and to determine if viral loads were predictive of disease severity, as different countries use different disease severity classification criteria. Using the WHO 1997 dengue disease classification we found that there was a trend towards viral loads being higher in those who progressed to DHF when infected with DENV2 and DENV3, although such a trend was not seen when the WHO 2009 dengue disease classification was used. Therefore, the viral loads did not appear to associate with subsequent disease outcomes, irrespective of the disease classification used. However, previous studies using different clinical disease severity classifications have shown that viral loads at presentation do in fact associate with subsequent disease severity in children with low levels if DENV antibody titres [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. A large study in Vietnam too showed that higher viral loads in the febrile phase was associated with increased risk of hospitalization and plasma leakage, although the risk was modest [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Although we did not find viraemia levels associate with disease severity, the viral loads did inversely correlate with the extent of thrombocytopenia, as shown in previous studies [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe found significant differences in the viral loads in patients infected with different serotypes, with viral loads being highest with DENV3 and lowest with DENV2. As reported previously from a large study in Vietnam, and many other studies, we found that DENV2 was associated with lower viral loads, but with a higher risk of developing DHF [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Higher viral loads for DENV1, followed by DENV3 has been shown in two previous studies from Vietnam [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] further showing that the kinetics of viral loads significantly differ between the DENV serotypes during early illness. As certain genotypes of the DENV appears to associate with increased disease severity (cosmological strain of DENV2) and with certain neurological complications, it would be important to further evaluate the differences in viral loads and kinetics for these different DENV genotypes [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Furthermore, these differences in the viral loads and NS1 antigen levels of different DENV serotypes, have significant implications when evaluating point-of care diagnostics and antiviral drugs for dengue. Therefore, in such evaluations, it would be important to carry out studies in them across different geographical regions and populations, which may have different circulating DENV serotypes and genotypes.\u003c/p\u003e \u003cp\u003eAlthough many studies do not show a statistically significant association with viral loads and clinical disease severity, many have shown a trend towards increased disease severity when infected with DENV2 [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], which had the lowest viral loads of the DENV serotypes. It is possibly due to greater immune evasive capacity by DENV2 infection, as strains of DENV2 have shown an enhanced ability to inhibit type 1 interferon signaling compared to other DENV serotypes [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Apart from these variations seen between DENV serotypes and particular genotypes, there is a huge individual variation between viral loads. Our data along with many other studies show several log differences of viral loads for different DENV serotypes in patients with varying disease severity during the febrile phase. Many factors such as the initial viral inoculum, the incubation period, previous immunity, and presence of comorbid illnesses have shown to affect viral loads [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. It was shown that the incubation period was shorter in those with secondary dengue compared to primary infection, supporting the role of antibody dependent enhancement in disease pathogenesis [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAlthough we analyzed the differences in viral loads in the febrile phase in those with primary and secondary dengue, the sample size was small and only a few patients were infected with DENV1 and DENV3, to include in analysis. However, our results were similar to the large study done in Vietnam comparing viral loads in relation to immune status, which showed no difference in early illness [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. A previous study done in Vietnam and in Singapore for evaluation of the antiviral effect of celgosivir showed that the viral loads were not in fact different in the early phase, but those with secondary dengue, cleared the plasma viraemia earlier than those with primary dengue [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Therefore, although patients with secondary dengue have shorter incubation periods and possibly higher viral infection in FcγR bearing cells, due to antibody dependent enhancement, this is not reflected in the viraemia seen in serum. This possibly suggests that the viral loads and viral kinetics seen in serum may not necessarily reflect the viraemia within immune cells and tissues.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn summary, although the degree of viraemia leads to severe disease, there is an important role played by the host-immune response to which could lead to resolution of infection or lead to immunopathogenesis. While use of antivirals would be an important treatment strategy for dengue, drugs that target certain immune mediators, such as leukotrienes, chymase, tryptase, platelet activating factor, growth factors, cytokines and other lipid mediators would be of potential benefit.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was obtained from the Ethics Review Committee of the Faculty of Medical Sciences, University of Sri Jayewardenepura (58/19).\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\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data is available in the manuscript, figures and the supporting files\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe are grateful to the NIH, USA (grant number 5U01AI151788-02),\u0026nbsp;Accelerating Higher Education Expansion and Development (AHEAD) Operation of the Ministry of Higher Education funded by the World Bank,\u0026nbsp;and the UK Medical Research Council.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConceptualization: GNM, CJ, GSO\u003c/p\u003e\n\u003cp\u003eData curation: HK, TS, NLAS, AW\u003c/p\u003e\n\u003cp\u003eLaboratory investigations and methodology: SD, HK, TS, LG, DA, STR\u003c/p\u003e\n\u003cp\u003eData analysis: SD, GNM\u003c/p\u003e\n\u003cp\u003eProject administration and supervision: GNM, CJ, AW\u003c/p\u003e\n\u003cp\u003eFunding acquisition: GNM, CJ, GSO\u003c/p\u003e\n\u003cp\u003eWriting the initial draft: SD, GNM\u003c/p\u003e\n\u003cp\u003eReview and editing the final draft: GSO, GNM\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eWHO. 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Dengue incidence and length of viremia by RT-PCR in a prospective observational community contact cluster study from 2005\u0026ndash;2009 in Indonesia. PLoS Negl Trop Dis. 2023;17(2):e0011104. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1371/journal.pntd.0011104\u003c/span\u003e\u003cspan address=\"10.1371/journal.pntd.0011104\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSung C, Wei Y, Watanabe S, Lee HS, Khoo YM, Fan L, et al. Extended Evaluation of Virological, Immunological and Pharmacokinetic Endpoints of CELADEN: A Randomized, Placebo-Controlled Trial of Celgosivir in Dengue Fever Patients. PLoS Negl Trop Dis. 2016;10(8):e0004851. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1371/journal.pntd.0004851\u003c/span\u003e\u003cspan address=\"10.1371/journal.pntd.0004851\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\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":"bmc-infectious-diseases","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"infd","sideBox":"Learn more about [BMC Infectious Diseases](http://bmcinfectdis.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/infd","title":"BMC Infectious Diseases","twitterHandle":"#bmcinfectdis","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-4771323/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4771323/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eAs\u003cstrong\u003e \u003c/strong\u003emany studies have shown conflicting results regarding the extent of viraemia and clinical disease severity, we sought to investigate if viraemia during early dengue illness is associated with subsequent clinical disease severity.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Realtime PCR was carried out to identify the dengue virus (DENV serotype), in 362 patients, presenting within the first 4 days of illness, from 2017 to 2022, in Colombo Sri Lanka. To characterize subsequent clinical disease severity, all patients were followed throughout their illness daily and disease severity classified according to WHO 1997 and 2009 disease classification.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e 263 patients had DF, 99 progressed to develop DHF, and 15/99 with DHF developed shock (DSS). Although the viral loads were higher in the febrile phase in patients who progressed to develop DHF than in patients with DF this was not significant (p=0.5). Significant differences were observed in viral loads in patients infected with different DENV serotypes (p=0.0009), with lowest viral loads detected in DENV2 and the highest viral loads in DENV3. \u0026nbsp;Sub-analysis for association of viraemia with disease severity for each DENV serotyped was again not significant. Although those infected with DENV2 had lower viral loads, infection with DENV2 was significantly associated with a higher risk of developing DHF (p=0.011, Odds ratio 1.9; 95% CI 1.164 to 3.078). Based on the WHO 2009 disease classification, 233 had dengue with warning signs (DWW), 114 dengue without warning signs (DWoWS), and 15 had severe dengue (SD). No significant difference was observed in the viral loads between those with SD, DWW and DWoWS (p=0.27).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eViral loads were significantly different in the febrile phase between different DENV serotypes, and do not appear to significantly associate with subsequent clinical disease severity in a large Sri Lankan cohort.\u003c/p\u003e","manuscriptTitle":"Are viral loads in the febrile phase a predictive factor of dengue disease severity?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-26 15:57:02","doi":"10.21203/rs.3.rs-4771323/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-09-17T07:24:54+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-16T22:04:33+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-09T10:53:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"60469864805635847298185122778856557645","date":"2024-09-08T09:36:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"39388106496276153254675067563630341669","date":"2024-09-06T08:40:08+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-05T13:50:49+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"337941440251687943465525016938170531526","date":"2024-08-31T02:17:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"6922396675497785966926528020664054524","date":"2024-08-30T17:41:57+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-08-21T02:17:27+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"85413603119056133303207122953760317573","date":"2024-08-12T22:07:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"89273213389311718371940910988879307980","date":"2024-08-12T06:11:01+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"114058966366860713626718471560294220356","date":"2024-08-11T04:34:09+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"264540079469031950213403909030778954179","date":"2024-08-09T06:20:56+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-08-09T01:26:41+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-07-30T20:35:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-07-24T01:40:48+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-07-23T13:34:23+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Infectious Diseases","date":"2024-07-20T05:19:36+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-infectious-diseases","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"infd","sideBox":"Learn more about [BMC Infectious Diseases](http://bmcinfectdis.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/infd","title":"BMC Infectious Diseases","twitterHandle":"#bmcinfectdis","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2fbf2967-87be-478e-8da8-fdc7d3a8d702","owner":[],"postedDate":"August 26th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-11-11T16:00:45+00:00","versionOfRecord":{"articleIdentity":"rs-4771323","link":"https://doi.org/10.1186/s12879-024-10152-2","journal":{"identity":"bmc-infectious-diseases","isVorOnly":false,"title":"BMC Infectious Diseases"},"publishedOn":"2024-11-05 15:57:25","publishedOnDateReadable":"November 5th, 2024"},"versionCreatedAt":"2024-08-26 15:57:02","video":"","vorDoi":"10.1186/s12879-024-10152-2","vorDoiUrl":"https://doi.org/10.1186/s12879-024-10152-2","workflowStages":[]},"version":"v1","identity":"rs-4771323","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4771323","identity":"rs-4771323","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}