Introduction India ranks among the top 30 countries with the highest incidence of dengue disease. The first indigenous vaccine to combat all four dengue serotypes is planned to have a market entry by 2027. Thus, determining the infecting serotype through molecular assays becomes essential. The objectives of the study are to determine the circulating serotype in dengue-positive cases and to examine the relationship between serotype and disease severity. Methodology Suspected dengue samples with less than or equal to 5 days post-disease onset (acute-phase samples) were subjected to dengue nonstructural protein 1 (NS1) enzyme-linked immunosorbent assay (ELISA), and positive serum samples were further serotyped. For samples with more than 5 days post-onset (late-phase samples), DENV immunoglobulin M (IgM) ELISA was performed, and further dengue IgM-positive sera samples were processed for RT-PCR to detect DENV RNA. DENV RNA-positive samples were serotyped. Results All 30 dengue serotype-positive patients presented with fever (100%), with headache as the second most common symptom ( n = 12, 40%). Thrombocytopenia was observed in eight (26.7%) patients, of whom three required platelet transfusion. No cases showed hemorrhagic manifestations or features of plasma leakage. The median duration of hospital stay was 7 days interquartile range (IQR): 5.25–10 days, and clinical recovery was documented in 25 (83.3%) patients. Serotype analysis demonstrated circulation of dengue virus serotype-1 (DENV-1), DENV-2, and DENV-3, with DENV-2 being the predominant serotype (50%). Notably, eight (27%) cases showed hybrid serotype infections, indicating concurrent circulation of multiple dengue virus serotypes. Conclusion This study emphasizes the hyperendemic nature of dengue in India, with DENV-2 as the predominant circulating serotype, whereas DENV-4 was not identified and appears to be less frequently reported in the region. The dynamic replacement of dominant serotypes over time depends on multiple factors and warrants further study; mixed serotype infections in a substantial proportion of cases indicate simultaneous circulation of multiple serotypes.
Shete et al. (Mon,) studied this question.