Molecular epidemiological analysis of measles virus in Beijing from 2015 to 2019
10.3760/cma.j.cn112309-20201222-00562
- VernacularTitle:2015—2019年北京市麻疹病毒分子流行病学分析
- Author:
Xiali YU
1
;
Jiazi ZHANG-ZHU
;
Yin FU
;
Xue WANG
;
Fang HUANG
;
Meng CHEN
Author Information
1. 北京市疾病预防控制中心 北京市预防医学研究中心 免疫预防所 100013
- Keywords:
Measles;
Measles virus;
H1a genotype;
D8 genotype;
B3 genotype;
Molecular epidemiology
- From:
Chinese Journal of Microbiology and Immunology
2021;41(8):623-628
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the molecular epidemiological characteristics of measles virus (MV) in Beijing from 2015 to 2019, and to provide laboratory basis for measles elimination.Methods:Measles virus-positive throat swab samples were collected through the Beijing Measles Laboratory network from 2015 to 2019. After the viral nucleic acid was extracted, 450 nucleotide fragments of the C terminal of the N gene of MV were amplified by RT-PCR. Nucleotide sequencing was performed for the amplified products. The phylogenetic tree was constructed with the representative strains of WHO measles virus genotype D8 genotype reference strains in China and other countries. Genotype identification was conducted and the nucleotide and amino acid homology analysis was carried out. A descriptive analysis of measles cases with D8 and B3 genotypes was conducted.Results:From 2015 to 2019, the genotypes of 546 MV were identified in the city, including 531 of H1a genotype, five vaccine strains, one of B3 genotype, and nine of D8 genotype, among which eight were epidemic strains in 2019. The homology of indigenous H1a genotype MV nucleotide and amino acid was 91.5%-100.0% and 73.6%-100.0%.In 2019, all eight cases of D8 genotype measles were adults, with two being an outbreak and the remaining six sporadic cases.Conclusions:The imported D8 genotype had become the main MV genotype in Beijing in 2019. With the decrease of measles incidence in 2019, native genotype H1a was no longer dominant, while other different genotypes were imported, forming a mixed epidemic trend. It was suggested that in the elimination of measles in Beijing, efforts should be made not only to block the transmission of local measles virus, but also to prevent and control the import and continuous transmission of non-local genotype virus, so as to avoid the risk of establishing local transmission by gradually evolving into a dominant strain.
