Abstract
BACKGROUND: Human parainfluenza virus-1 (HPIV-1) is a notable pathogen instigating acute respiratory tract infections in children. The article is to elucidate the epidemiological and genetic characteristics of HPIV-1 circulating in Hangzhou during the period of 2021-2022. METHODS: A cohort of 2360 nasopharyngeal swabs were amassed and subsequently examined via RT-PCR, with HPIV-1 positive samples undergoing P gene sequencing. RESULTS: The highest HPIV-1 infection rates were found in children aged between 3 and 6 years. A pronounced positive rate persisted through the latter half of 2021, with a notable decline observed in the initial half of 2022. All HPIV-1 strains could be clustered into 2 groups: Cluster 1, with strains similar to those found in Japan (LC764865, LC764864), and Cluster 2, with strains similar to the Beijing strain (MW575643). CONCLUSION: In conclusion, our study contributes to the comprehensive data on the epidemiological and genetic characteristics of HPIV-1 in pediatric patients from Hangzhou, post the COVID-19 peak.