Study on the molecular epidemiological characteristics of norovirus in acute gastroenteritis of Beijing

Objective To study the prevalence,genotypes and molecular characteristics of norovirus (NoV) in acute gastroenteritis.Methods RT-PCR was used to determine the molecular epidemiology of NoV.Results Out of 685 samples,66 positive specimens were identified and the prevalence was 9.6％ (66/685),9.9％ in males and 9.4％ in females,respectively,with no significant difference.The prevalence rates showed no differences between age groups or between inpatients and outpatients.NoV gastroenteritis did not present any seasonal distribution.43 out of the 66 specimens were classified,with 10 (22.7％) belonged to G Ⅰ including 2 G Ⅰ.3,1 G Ⅰ.4,4 G Ⅰ.5 and 3 G Ⅰ.7.Other 33 (77.3％) belonged to G Ⅱ genogroup,including G Ⅱ.4 accounted for 60.6％ (20/33) and followed by 7 G Ⅱ.12,2 G Ⅱ.6,1 G Ⅱ.2,1 G ⅡⅡ.3,1 G Ⅱ.5.Six specimens mixed with G Ⅰ and G Ⅱ and 3 specimens were classified as G Ⅰ.3/G Ⅱ.7,G Ⅰ.5/G Ⅱ.5 and G Ⅰ.4/G Ⅱ.4.Conclusion The main symptoms of acute gastroenteritis were abdominal pain,nausea,vomit and fever.There were many genotypes identified in our study and the main genotypes were G Ⅱ.4/2006a and 2006b.G Ⅰ and G Ⅱ could be coinfected with each other. Key words: Norovirus; Acute gastroenteritis; Molecular epidemiology