Molecular epidemiological analysis of norovirus in patients with acute gastroenteritis in Zhejiang province during 2016 / 临床检验杂志

ABSTRACT

Objective To explore the molecular epidemiological characteristics of norovirus isolated from the patients with acute gastroenteritis in Zhejiang province during 2016.Methods The stool samples and clinical data of 1 308 patients with acute gastroenteritis were collected from January to December in 2016.The type Ⅰ and Ⅱ of norovirus in stool samples were detected by one-step double real-time RT-PCR.Some of the positive specimens were selected by stratified sampling and amplified by conventional RT-PCR,and the PCR products were sequenced for genotype identification and phylogenetic analysis.Results Among the samples studied the positive rate of norovirus was 10.55％ (138/1 308) in which 12 cases were GⅠ genotype,118 cases were G Ⅱ genotype and 8 cases were mixed infection of G Ⅰ/G Ⅱ genotypes.The positive rate of norovirus in different age groups decreased with the increased age of patients,and became the lowest in the patient group of more than or equal to 60 years old.There was no significant difference for the positive rates of norovirus in different genders.Norovirus infection was distributed throughout all the year with the peak value of positive rate (37.50％) in December.The sequence analysis demonstrated that G Ⅱ.4 and G Ⅱ.17 genotypes were the prevalent strains of G Ⅱ genotypes with proportions of 40.91％ (18/44) and 34.09％ (15/44),while GⅠ.6 genotype was the prevalent strain of GⅠ genotypes.Conclusion Norovirus should be the important pathogen causing acute gastroenteritis in Zhejiang province during 2016.G Ⅱ.4 and G Ⅱ.17 of norovirus may be the predominant epidemic genotypes.