绍兴市MSM人群HIV-1分子传播网络特征分析

HIV-1 molecular transmission network among men who have sex with men in Shaoxing City

目的 分析浙江省绍兴市男男性行为人群(MSM)艾滋病病毒1型(HIV-1)分子传播网络特征,为MSM人群艾滋病防治提供依据。方法 选择2021年1月—2023年9月绍兴市新报告MSM人群艾滋病病毒感染者和艾滋病患者(HIV/AIDS)为研究对象,收集抗病毒治疗前血浆样本,采用反转录PCR和巢式PCR扩增HIV-1 pol基因,构建系统进化树分析基因亚型;采用HIV-TRACE法构建1.5%基因距离的分子传播网络,分析成簇情况和分子簇内病例特征。结果纳入2021年1月—2023年9月绍兴市MSM人群HIV/AIDS病例216例,获得合格序列179例。HIV-1亚型以CRF07_BC和CRF01_AE为主,分别为95和66例。在1.5%基因距离下共形成20个分子簇,61个节点和58条边。61条序列入网,入网率为34.08%。绍兴市各县(市、区)均有MSM人群HIV/AIDS病例入网。节点数≥10个的大分子簇1个,涉及5个县(市、区) 12例病例;节点数4~5个的中分子簇3个;节点数2~3个的小分子簇16个。边数≥4条的高传播风险病例有7例,均为CRF07_BC亚型;其中2例来自大分子簇,5例来自嵊州市、新昌县病例组成的同一分子簇。结论 绍兴市MSM人群HIV/AIDS病例HIV-1基因亚型以CRF07_BC和CRF01_AE为主,存在跨地区HIV传播,嵊州市和新昌县可能存在潜在传播风险点。

Objective To investigate the molecular transmission network characteristics of HIV-1 among men who have sex with men(MSM)in Shaoxing City,Zhejiang Province,so as to provide insights into AIDS prevention and control among MSM.Methods Newly reported HIV/AIDS cases among MSM in Shaoxing City were selected from January 2021 to September 2023.Plasma samples before the antiviral treatment were collected.The HIV-1 pol gene was amplified using reverse transcription PCR and nested PCR to construct phylogenetic trees for gene subtype analysis.The HIV-TRACE method was used to construct a molecular transmission network with a genetic distance of 1.5%to analyze clustering and the characteristics of cases within molecular clusters.Results A total of 216 HIV/AIDS cases among MSM were included,and 179 qualified sequences were obtained.The predominant HIV-1 subtypes were CRF07_BC and CRF01_AE,with 95 and 66 cases,respectively.At 1.5%genetic distance,20 molecular clusters were formed,with 61 nodes and 58 edges.A total of 61 sequences were connected to the transmission network(34.08%).HIV/AIDS cases among MSM from all the counties(cities,districts)in Shaoxing City were included in the network.There was the largest molecular cluster with≥10 nodes,involving 12 cases from five counties(cities,districts),3 medium-sized molecular clusters with 4 to 5 nodes,and the 16 small-sized molecular clusters with 2 or 3 nodes.Seven cases with high risk of transmission,each with≥4 edges,were all CRF07_BC subtypes.Among them,two cases were from the large molecular cluster,and five cases were from the same molecular cluster composed of cases from Shengzhou City and Xinchang County.Conclusions The predominant HIV-1 subtypes among MSM in Shaoxing City were CRF07_BC and CRF01_AE.There was cross-regional HIV transmission,and potential transmission risk might exist in Shengzhou City and Xinchang County.