[Surveillance for viral diarrhea in sentinel hospitals in Henan province, 2013-2015]

Objective: To investigate the infection status of human rotavirus, calicivirus, astrovirus and enteric adenovirus in children aged <5 years in disease surveillance areas in Henan province from 2013 to 2015. Methods: A total of 880 stool samples were collected from four sentinel hospitals and group A rotavirus was detected by ELISA and group A rotavirus G/P genotyping was performed with nested multiplex RT-PCR, while rotavirus (group B, C), calicivirus and astrovirus were detected by two-step multiplex RT-PCR and adenovirus were detected by PCR. The epidemiological data of positive cases were statistically analyzed. Results: A total of 594 positive samples were detected, including 24 mixed infection samples, 370 rotavirus positive samples (42.0%); 162 calicivirus positive samples (18.4%); 69 astrovirus positive samples (7.8%) and 17 enteric adenovirus positive samples (1.9%). The overall positive rate of four viruses was significantly higher in urban area than in rural area, but the positive rate of rotavirus was higher in males than in females and in younger age group than in older age group. G9P [8] was the major genotype of group A rotavirus, there were two seasonal infection peaks in autumn and spring. Norovirus Ⅱ was the predominant type of calicivirus and the infection peak was in spring. Viral diarrhea cases were distributed in different age groups, mainly in age groups 0-12 months (rotavirus) and 3-5 years (calicivirus). The main clinical symptoms included fever, diarrhea and vomiting. The etiological characteristics differed with gender and area. Conclusions: The infection rate of diarrheal viruses was higher in young children <5 years old in disease surveillance areas. The epidemiological and clinical features varied with the type of pathogen.