Abstract
BACKGROUND: In 2022, a widespread dengue outbreak was reported in Nepal, with 4,593 cases reported by August escalating to 53,951 cases and 62 deaths by November. The caseload was significantly higher than in 2019, when the outbreak was last officially recorded with 17,999 cases and 6 fatalities. AIMS AND OBJECTIVES: This study aimed to identify Nepal's circulating dengue virus serotypes during the 2022 outbreak and analyze their distribution across different regions and hospitals. MATERIALS AND METHODS: To better understand the circulating dengue virus serotypes, a study was conducted in collaboration with the Seven Provincial Hospital and National Public Health Laboratory (NPHL) with the Coordination of Epidemiology Diseases Control Division (Nepal). This study involved collecting and testing blood samples from various Provincial hospitals across Nepal, covering all the geographical patterns of Nepal. RESULTS: The results revealed a predominance of serotype 1, followed by serotypes 2 and 3, with some mixed infections. The findings underscore the diverse dengue serotype circulation and the potential for severe dengue infections in Nepal. CONCLUSION: The 2022 dengue outbreak in Nepal was primarily driven by DENV-1, followed by DENV-2 and DENV-3. The detection of mixed infections and the absence of DENV-4 warrant further investigation to understand the transmission dynamics and potential for severe dengue cases.