Epidemiology of classic human astrovirus among infants and young children with acute diarrhea in a hospital outpatient in Shanghai, 2012-2016 / 中华传染病杂志

ABSTRACT

Objective:To investigate the epidemiological characteristics of classic human astrovirus (HAstV) among children under five years old with acute diarrhea, and to understand the role of HAstV in children acute diarrhea.Methods:A total of 1 010 fecal specimens were collected in 1 010 outpatients under five years old with acute diarrhea admitted to Children′s Hospital of Fudan University, Shanghai from January 2012 to December 2016. Reverse transcription polymerase chain reaction (PCR) or PCR was used for screening classic HAstV, group A rotavirus, norovirus and adenovirus. Genotypes of classic HAstV were determined by nucleotide sequencing and phylogenetic tree analysis.Results:The overall positive rate of classic HAstV was 2.7%(27/1 010). The detection rates of classic HAstV from 2012 to 2016 were 6.9%(10/144), 3.5%(5/144), 2.1%(3/144), 1.5%(4/265) and 1.6%(5/313), respectively. Almost 96.3%(26/27) of children infected with HAstV were 0 to 36 months of age. The prevalence of classic HAstV infections displayed a typical autumn/winter seasonality except in 2016. All the positive classic HAstV strains were genotyped as HAstV-1 with two lineages of HAstV-1a and HAstV-1b. Among them, the lineage of HAstV-1a was the predominant subtype (63.0%, 17/27). There were 77.8%(21/27) of the children with acute diarrhea only infected with classic HAstV, whereas for the remaining cases a variety of other enteric viruses were detected (three cases co-infected with HAstV and group A rotavirus, two cases co-infected with HAstV and adenovirus, and one case co-infected with HAstV, group A rotavirus and adenovirus).Conclusions:Children infected with HAstV are mainly less than 36 months of age. Although the genotype of classic HAstV detected in this study is single, but the lineages are in a state of dynamic change. Long-time and continuous monitor for the epidemiology of classic HAstV is needed to avoid outbreak of diarrhea in children.