Prevalence and distribution of dengue virus serotypes among seropositive patients at a tertiary care center: A retrospective study

Abstract Introduction: Dengue fever, a significant public health threat in tropical and subtropical regions, is caused by any of the five dengue virus serotypes (DENV-1 to DENV-5). The study aims to evaluate the prevalence of dengue virus serotypes and dual serotype infection among serologically positive patients using reverse transcription-polymerase chain reaction (RT-PCR). Materials and Methods: This observational study was conducted retrospectively in the virology laboratory of a tertiary care institute in Eastern India from January to October 2020 on 250 plasma samples from suspected dengue cases of all age groups. Real-time RT-PCR was done on 54 serologically positive samples for serotype identification in February 2021. Data analysis was conducted using MS Excel and OpenEpi. Results: Out of 250 samples tested, 54 (21.6%) were serologically positive for dengue nonstructural protein 1 antigen and/or dengue immunoglobulin M (IgM) with or without dengue IgG. Serotyping was successfully performed on 36 (66.66%) of these serologically positive samples. Among these, 35 cases (97.22%) were identified as being caused by the DENV-1 serotype, while only 1 case (2.7%) was attributed to DENV-2 serotype. No dual infecting serotype was detected, and higher prevalence was observed in males aged 20–29 years (41.66%), followed by those in the 30–39-year age group (27.77%). Conclusion: The study using RT-qPCR identified DENV-1 as the dominant serotype, accounting for 97.22% of infections, these findings underscore the importance of ongoing molecular surveillance and also provide a critical baseline for future research efforts and underline the necessity for targeted public health initiatives in the region.