Genetic and epidemiological characteristics of enterovirus 71 VP1 region in children with hand, foot and mouth disease in Shenzhen from 2016 to 2022
10.3760/cma.j.cn112309-20231212-00174
- VernacularTitle:2016—2022年深圳市肠道病毒71型流行情况及VP1区基因特征分析
- Author:
Kai LI
1
;
Long CHEN
;
Yaqing HE
;
Jun MENG
;
Hong YANG
;
Ziquan LYU
;
Xiangjie YAO
;
Hailong ZHANG
Author Information
1. 山西医科大学公共卫生学院营养与食品卫生学教研室，太原 030001
- Keywords:
Hand, foot and mouth disease;
Enterovirus 71;
VP1 gene;
Mutation;
Genotype
- From:
Chinese Journal of Microbiology and Immunology
2024;44(6):519-524
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the prevalence of enterovirus 71 (EV71) and the genetic characteristics of VP1 region in common hand, foot and mouth disease (HFMD) cases in Shenzhen from 2016 to 2022.Methods:Throat swabs from mild HFMD in Shenzhen sentinel hospitals were collected from 2016 to 2022. A total of 38 EV71-positive samples were screened from these throat swabs and were sequenced. Then, the VP1 sequence of these EV71-positive samples were analyzed for their phylogenetic evolution by bioimformatics software DNAStar and MEGA 6.Results:From 2016 to 2022, the number of EV71 infections among HFMD patients in Shenzhen sentinel hospitals decreased from 136 in 2016 to 0 in 2022. The mumber of EV71 infections in 2018 and 2019 decreased by 96.3%(257/267) compared to that in 2016 and 2017. From 2020 to 2022, the number of EV71 infections decreased to 0. During this period, the EV71 vaccination rate among HFMD patients increased from 6.4% to 39.6%; Evolutionary analysis showed that the nucleotide homology and amino acid homology between 38 EV71 sample strains in Shenzhen from 2016 to 2022 were 91.8%-99.9% and 98.3%-100.0%, all belonging to the C4a subgenotype; Among them, 26 strains wene local epidemic strains, and 11 strains were imported from other provinces, with a close genetic relationship with epidemic strains in Hainan, Yunnan, Sichuan, Tianjin, Henan, Jilin, and other places. One strain from 2017 had the closest genetic relationship with the US epidemic strain OP207969-USA-2017. Further comparing the EV71 epidemic strains in Shenzhen from 2016 to 2022 and EV71 severe strains, it was found that the EV71 strains in Shenzhen carried four amino acid mutation sites related to severe condition, named R22H, K43R, I249V and T289A.Conclusions:The EV71 epidemic strains in Shenzhen from 2016 to 2022 all belong to the C4a subgenotype, and the number of EV71 infection shows a downward trend with the increase of vaccine coverage rate. At the same time, the distribution of EV71 virus strains in Shenzhen shows a significant decrease in local strains and a predominance of imported strains. There are a total of four amino acid mutation sites associated with severe cases in the EV71 sample strains in Shenzhen from 2016 to 2022. Among them, 22R and 289T are located at the N and C ends of VP1, which are related to EV71 adsorption and targeting cells. The 43R site is associated with binding ability to Annexin2 protein, which enhances cell binding ability.
