Molecular epidemiological characteristics of Human Calicivirus in Kunming city, 2014-2015 / 中华实验和临床病毒学杂志

ABSTRACT

Objective@#To investigate the molecular epidemiological characteristics of Human Calicivirus (HuCV) infection among children less than 5 years in Kunming city, Yunnan province, it might be provide effective evident for prevention and control the diarrhea related with HuCV infection.@*Methods@#Four sentinel hospitals were recruited in the study from Kunming city, Yunnan province, 850 diarrhea cases and 170 non-diarrhea subject were recruited in this study from 2014 to 2015. RT-PCR was performed to screen HuCV infection, and gene sequencing was used to ensure positive infection subtypes and genotypes.@*Results@#The positive rate of HuCV was higher in children with diarrhea than in non-diarrhea children (11.5%, 98/85; 4.7%, 8/170, χ2=7.083, P=0.008), and the positive rate of Norovirus (NoV) GII was higher in non-diarrhea children were (11.1%, 94/85; 4.7%, 8/170, χ2=6.353, P=0.012). There was no significant difference in the positive rate of NoV GI (0.1%, 1/850; 0.0%, 0/170, P=0.833) and Sappovirus (0.4%, 3/850; 0.0%, 0/170, P=0.578) in diarrhea children and non-diarrhea children. GII.P4 (10%, n=102) was the most important genotype of NoV GII detected in diarrhea and non-diarrhea individuals. Despite no significant difference in Norovirus GII infection between different age groups (χ2=0.038, P=0.846) and sex(χ2=0.620, P=0.733), infection rate of NoV GII varied with season (χ2=9.867, P=0.020), having close relationship with diarrhea in autumn (15.6%), primarily caused by GII.4 and GII.12 genotype (χ2=8.881, P=0.031; χ2=7.917, P=0.039).@*Conclusions@#NoV GII diarrhea had higher epidemic rate, which was caused by multiple genotypes, GII.P4 was a dominant genotype, and was a major pathogenic agent of diarrhea in infants f in Kunming city.