石家庄市2013-2016年含麻疹成分疫苗接种偶合麻疹野病毒感染病例分析

Measles cases caused by coincidental wild measles virus infections after receipt of measles containing vaccine in Shijiazhuang city,2013-2016

目的对石家庄市2013-2016年接种含麻疹成分疫苗(Measles containing vaccine,MCV)后麻疹病例进行麻疹病毒型别鉴定。方法对接种MCV后麻疹病例血清和咽拭子标本,采用酶联免疫吸附试验(ELISA)和荧光RTPCR法分别测定麻疹IgM抗体和麻疹病毒核酸,再进行病毒培养,采用RT-PCR扩增麻疹病毒核蛋白基因片段,然后进行测序分析。结果 9例接种MCV后麻疹病例的麻疹病毒分离株均属于H1基因亚型,与北京H1基因型麻疹野病毒核苷酸和氨基酸序列的同源性为99.6%-100%,与中国S191疫苗株核苷酸和氨基酸序列同源性为91.7%。结论本研究中接种MCV后出现的麻疹病例均为偶合H1基因型麻疹野病毒感染所致,非疫苗相关麻疹病例。

Objective To identify the genotypes of measles viruses causing measles cases after vaccination with measles containing vaccine （MCV） in Shijiazhuang city, 2013-2016. Methods We collected ser- um and throat swab samples from post-MCV immunization measles cases to test for measles IgM antibody by enzyme-linked immunosorbent assay （ELISA） and to recover measles virus nucleic acid by quantita- tive fluorescence RT-PCR. Virus cultures and RT-PCR were used to amplify the nucleic acids for sequence analysis. Results Nine strains of measles viruses were isolated from post-MCV immunization measles cases; all were genotype H1 ,with a 99.6%-100% homology of nucleotides and amino acids com- pared with a Beijing wild measles virus genotype Hl strain, and with a 91.7% homology compared with the China S191 vaccine strain. Conclusions The post-MCV immunization measles cases in this study were caused by coincidental infections by wild measles viruses, and not by measles vaccine.