2020年西藏自治区0~5岁健康儿童肠道病毒的流行和分布

Epidemic and distribution of enterovirus in healthy children aged 0-5 years in Tibet Autonomous Region in 2020

目的研究中国西藏自治区2020年0~5岁健康儿童中人肠道病毒的流行和分布。方法粪便标本取自2020年中国西藏自治区574名0~5岁的健康儿童。使用实时荧光聚合酶链反应(polymerase chain reaction,PCR)检测粪便标本中的肠道病毒核酸。对肠道病毒核酸阳性的标本,采用逆转录PCR扩增肠道病毒VP1区并进行序列测定和分析,根据测定的序列进行肠道病毒分子分型。结果574例样本中检出肠道病毒(enterovirus,EV)核酸阳性89份(15.98%),EV-B检出最多,检出率为10.98%,EV-A和EV-C检出率分别为3.66%和0.87%,未发现EV-D。共鉴定出17种血清型,主要血清型为E11(7.67%),其次为EV-A71(1.74%)。各年龄组感染率存在一定的差异,呈现为随着年龄的增大感染率逐渐降低的现象,0岁和1岁组感染率分别为23.4%和25.0%,而在5岁组感染率降为最低,仅为5.8%。结论西藏自治区健康儿童粪便样本EV病原谱中以EV-B为主。序列分析提示了西藏自治区EV流行的广泛性及多样性,以EV-A71和E11为代表的几种EV型别在西藏自治区相对常见,有导致较严重疾病的潜力,需要进行更加严格的监测。

Objective To study the prevalence and distribution of human enterovirus(EV)in healthy children aged 0-5 years in Tibet Autonomous Region,China in 2020.Methods Stool specimens were collected from 574 healthy children aged 0-5 years in 2020 in Tibet Autonomous Region,China.EV nucleic acid in stool specimens was detected by real-time polymerase chain reaction(PCR).The VP1 region of EV was amplified by reverse transcription PCR for sequencing and analysis.Molecular typing of EV was performed according to obtained sequences.Results EV nucleic acid was detected in 89 of 574 samples(15.98%).EV-B was the most detected,with a detection rate of 10.98%.EV-A and EV-C were found in 3.66%and 0.87%of samples,respectively.No EV-D was found.A total of 17 serotypes were identified,the predominant serotype was E11(7.67%),followed by EV-A71(1.74%).There were differences in the infection rate among the age groups,which showed gradually decreasing of the infection rate as the age increasing.The infection rates were 23.4%and 25.0%in the 0-year-old and 1-year-old groups,respectively,while the lowest infection rate was as low as 5.8%in the 5-year-old group.Conclusions EV-B was the dominant pathogen in the stool samples of healthy children in Tibet Autonomous Region.Sequence analysis suggested the extensiveness and diversity of EV epidemics in Tibet Autonomous Region.Several EV types represented by EV-A71 and E11 are relatively common in the Tibet Autonomous Region and require more rigorous surveillance due to their potential to cause more severe disease.