Molecular epidemiology of group A rotavirus diarrhea in children in Shanghai / 中华传染病杂志

ABSTRACT

ObjectiveTo explore the molecular epidemiological characteristics of group A rotavirus diarrhea in children in Shanghai and to provide the background data for the implementation of rotavirus vaccination.MethodsA total of 910 stool samples were collected from the outpatient children with acute diarrhea from August 2008 to July 2009.Group A rotavirus was detected by usingcommercial colloidal gold device.Rotavirus strains were characterized for G and P genotypes using the nested reverse transcription polymerase chain reaction (RT-PCR).ResultsGroup A rotavirus was detected in 268(29.4％) out of 910 stool samples.Rotavirus infection was found year-round and the peak season was from October 2008 to January 2009,with the detection rates ranging from 38.3 ％ to 70.5％.Ninety-one percent of children (244 cases) with rotavirus-associated diarrhea occurred in children ＜3 years of age.The detection rate of rotavirus was highest (36.6％) in children aged 12-23 months.Among the 268 group A rotavirus-positive strains,G1 was the most common G genotype (65 strains),accounting for 24.3％,followed by G3 (40 strains,14.9％),G mixed genotypes (37strains,13.8 ％),G2 (27 strains,10.1％),G9 (14 strains,5.2％),G4(5 strains,1.9％),other G types (5 strains,1.9％),and unclassified G type (75 strains,28.0％).P[8] and P[4] were the most common P genotypes,accounting for 54.9％ (147 strains) and 11.9％ (32 strains),respectively,followed by P mixed genotypes (6 strains,2.2％) and other P genotypes (4 strains,1.5％),unclassified P type (79 strains,29.5％).The G/P genotype combinations were found as follows:G1P [8] (13.4％),G3P[8] (13.4％),GmixP[8] (10.1％),G1P[4] (8.2％),G9P[8] (2.2％),G2P [4] (1.9％),G1Pmix (1.9％).ConclusionsGroup A rotavirus is a major causative agent of diarrhea in infants and young children in Shanghai.The peak season of rotavirus infection appears in fall and winter.The currently licensed rotavirus vaccines cover the majority of genotypes of rotavirus strains prevailing in Shanghai.