Epidemiology analysis on severe and dead cases of hand, foot and mouth disease, and genetic characteristics of the VP1 region of enterovirus A71 in Shaanxi Province, China
XU Yi, SHI Wei, XU Jing, MA Ping, GUAN Lu-yuan, ZHENG Yuan, YU Peng-bo
Shaanxi Center for Disease Control and Prevention, Xi’an 710054, China
Abstract:We aimed to understand the epidemiological characteristics and genetic characteristics of human enterovirus71 (EV-A71) pathogen of severe and dead cases of hand, foot and mouth disease (HFMD) in Shaanxi Province, and to provide scientific evidence for the prevention and control of the disease. The case-data of HFMD in Shaanxi Province from the Chinese National Notifiable Infectious Disease Reporting System were analyzed. VP1 genes of EV71 strains isolated from HFMD severe and dead cases were amplified by RT-PCR. The homology comparison and phylogenetic trees were performed with MEGA5.0 software. A total of 5 054 HFMD severe cases and 118 dead cases were reported in Shaanxi Province from 2010 to 2015, the average annual mortality rate was 0.052 09/100 000 and the fatality rate was 2.32%. The incidence peak occurred during May-July, the highest incidence was found in the regions of Xi’an, Weinan and Xianyang of the province. The 90.84% severe cases and 93.22% dead cases were under the age of three, the male-to-female ratio was 1.67∶1. Pathogen surveillance indicated that the proportion of EV-A71, CV-A16 and other enteroviruses were 66.39%, 6.26% and 27.35% respectively. There were significant statistical differences of the type of pathogen in the different years. EV-A71 was the main pathogen in different age groups, the detection rate of EV-A71 increased with age. The dead cases were mainly caused by EV-A71 pathogen. A total of 29 strains of EV-A71 isolated from HFMD severe and dead cases were sequenced, the homology of nucleotides and amino acids among 29 strains were 94.2%~99.7% and 98.0%~100%, respectively. It was the highest homology with genotype C4 strains and all of isolated strains were belong to the C4a sub-genotype of EVA71. We should strengthen the surveillance in the prevalence season and carry out prevention and control in the important regions and children ≤3 years old,pay attention to the epidemic trend of EV-A71 and take effective measures to reduce the incidence of severe and dead cases.
徐艺,史伟,许晶,马萍,关路媛,郑媛,余鹏博. 陕西省手足口病重症和死亡病例的流行特征及肠道病毒71型VP1区基因特征分析[J]. 中国人兽共患病学报, 2018, 34(5): 411-415.
XU Yi, SHI Wei, XU Jing, MA Ping, GUAN Lu-yuan, ZHENG Yuan, YU Peng-bo. Epidemiology analysis on severe and dead cases of hand, foot and mouth disease, and genetic characteristics of the VP1 region of enterovirus A71 in Shaanxi Province, China. Chinese Journal of Zoonoses, 2018, 34(5): 411-415.