Etiological and phylogenetic analysis of hand, foot and mouth disease in Qujing city, Yunnan Province, 2020
10.3760/cma.j.cn112309-20210930-00324
- VernacularTitle:2020年云南省曲靖市手足口病病原学监测及基因特征分析
- Author:
Sisi CHANG
1
;
Xi YANG
;
Xiaoqing FU
;
Lili JIANG
;
Xiaofang ZHOU
;
Jianping CUN
;
Bingjun TIAN
Author Information
1. 昆明市疾病预防控制中心行政办，昆明 650228
- Keywords:
Hand, foot and mouth disease (HFMD);
Etiology;
Enterovirus species A;
Genetic characteristics analysis
- From:
Chinese Journal of Microbiology and Immunology
2022;42(2):148-155
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the etiological distribution and phylogenetic characteristics of hand, foot and mouth disease (HFMD) in Qujing city of Yunnan Province in 2020.Methods:Stool samples were collected from HFMD cases in Qujing city in 2020 and virus RNA was extracted directly from treated stool suspensions. Virus VP4 gene sequences were firstly amplified using MD91/OL68-1 primer pairs and sequenced, then the virus serotypes were determined by BLAST search on the GenBank. Virus entire VP1 gene sequences were amplified and sequenced. Virus serotypes were identified online using Enterovirus Genotyping Tool Version 0.1. Sequences of reference virus genotypes/sub-genotypes were downloaded according to references. Phylogenetic trees were constructed by MEGA5.2 software and the genetic characteristics were analyzed.Results:A total of 47 strains of enteroviruses (EVs) were detected with a detection rate of 10.22% (47/460). The detected viruses were coxsackievirus A4 (CVA4, 0.65%, 3/460), CVA6 (7.83%, 36/460), CVA10 (0.87%, 4/460) and CVA16 (0.87%, 4/460). All were enterovirus species A (EVA), while other group viruses were not detected. The predominant virus was CVA6, accounting for 7.83% (36/460). EVA71 was not detected. CVA4 strains of C2 and C4 subgenotypes were co-circulating strains in Qujing city. CVA6 subgenotype D3a and CVA16 subgenotype B1a were also circulated in Qujing city. All CVA10 strains were in a separate lineage.Conclusions:Similar to the previous situation in China, the detection rates of EVA71 and CVA16 were very low, even zero. This study showed that CVA6 was the predominant virus, indicating a HFMD outbreak caused by CVA6 in Qujing city in 2020. The phylogenetic analysis showed CVA10 isolates belonged to a separate lineage, which might be unique to Qujing city. Laboratory and molecular epidemiological surveillance of non-EVA71 and non-CVA16 viruses, especially CVA6 and CVA10 should be strengthened in the future.
