Pathogenic characteristics of viral diarrhea in children under five years of age in sentinel surveillance in Lulong County of Hebei Province, 2010-2020

Abstract

Objective: To analyze pathogenic characteristics of viral diarrhea in children aged <5 years in Hebei Province and provide reference for the prevention and control of viral diarrhea in children. Methods: Stool samples were collected from in-patients with diarrhea under five years old from sentinel hospitals in Lulong County of Hebei between 2010 and 2020. ELISA detected rotavirus antigen, and then positive samples were genotyped by semi nested reverse transcription PCR of two rounds. Calicivirus, genotyping astrovirus, and adenovirus were detected by real-time fluorescence quantification PCR. The data were analyzed by using software SPSS 20.0. Results: In 2 925 detected stool samples, 1 919 (65.61%) were positive. The positive rates of rotavirus, calicivirus, adenovirus, and astrovirus were 42.80% (1 252/2 925), 22.12% (647/2 925), 6.19% (181/2 925), 3.56% (104/2 925). Viral diarrhea was mainly caused by rotavirus infection, accounting for 59.30% (1 017/1 715) between 2010 and 2017, and by calicivirus infection accounting for 53.43% (109/204) between 2018 and 2020. The peak positive rate of rotavirus occurred in winter, with the highest rate in infants aged 12 to 17 months (52.96%,483/912). In the rotavirus positive samples, G9P[8] was mainly detected strains (58.31%,730/1 252), followed by G3P[8] (8.15%,102/1 252). The calicivirus-positive samples were mainly infected with norovirus GⅡ. Sequence analysis indicated that the main type was GⅡ.4 [P31] between 2011 and 2016 and GⅡ.3 [P12] in 2018. Conclusions: Rotavirus and calicivirus were the main pathogens causing infant diarrhea in children under five years old in Hebei from 2010 to 2020. Winter was the main epidemic season.