一大型HIV-1分子簇在某低流行县传播特征分析

Study on the epidemiological characteristics of a large HIV-1 molecular cluster in a low epidemic county

目的研究四川省某获得性免疫缺陷综合征(acquired immune deficiency syndrome,AIDS,也称艾滋病)低流行县HIV-1分子簇的特征,为开展精准干预提供依据。方法对四川省某AIDS低流行县2011年1月―2019年3月新诊断的人类免疫缺陷病毒(human immunodeficiency virus,HIV)感染者/AIDS病人(HIV/AIDS)测定其感染HIV-1 pol基因区序列,进行分子簇分析,并对存活病例进行流行病学问卷调查。结果新诊断的113个HIV/AIDS中,有49.6%(56/113)属于同一分子簇(CRF01AE4),该簇平均基因遗传距离为0.006 1,2011年发现首例,并呈持续快速增长的趋势(χ2趋势=11.626,P=0.001)。簇内病例以中老年[平均年龄(50.5±13.0)岁]、文盲或小学文化(42.9%)、已婚(67.9%)、男性(76.8%)为主,感染前鲜有外出史(17.0%),45.5%经异性商业性行为感染,性交易主要发生在本地(87.5%)、低档场所(55.0%),性交易从未坚持使用安全套。75.0%经异性商业性行为感染的簇内病例为2016年及之后诊断发现;1例在得知感染后仍保持高危性行为且拒绝抗病毒治疗,在分子传播簇中与多个病例有连接关系。结论一大型传播网络在某低流行县内持续快速扩张,本地低档场所性交易是导致该网络扩张的主要原因。

Objective To study the characteristics of HIV-1 molecular clusters in a low-epi-demic county in Sichuan Province,so as to provide a basis for precise intervention.Methods Research subjects included HIV/AIDS patients who were newly diagnosed from January 2011 to March 2019 in a low-epidemic county in Sichuan Province,of whom the HIV-1 pol gene was sequenced,and molecular cluster analysis was performed.Epidemiological questionnaire survey was conducted among survival cases.Results Among 113 newly diagnosed cases,49.6%(56/113)belonged to the same molecular cluster(CRF01_AE4),and the average genetic distance of this cluster was 0.0061.The first case was found in 2011 and there was a trend of continuous rapid growth(χ^2 trend=11.626,P=0.001).The cases in the cluster were mainly seniors(average age was 50.5±13.0),low-educated(42.9%),married(67.9%),male(76.8%)and only few had a going-out history(17.0%).45.5%were infected through heterosexual commercial sexual behaviors,and the sexual transactions mainly occurred in lowcost commercial sex venues(55.0%)in local areas(87.5%),and never consistently used condoms in the sex trade.75.0%cases who were infected through heterosexual commercial sex were mainly diagnosed since 2016.One case,who continued having high-risk sexual behaviors after being informed and refused the anti-retroviral therapy,was found connecting with multiple cases in the molecular transmission cluster.Conclusions A large-scale transmission network had continued to expand rapidly in a HIV low-endemic county and sexual transactions in local lowcost commercial sex venues were the main reason for the network expansion.