摘要目的:分析嘉兴市HIV/AIDS的感染和传播关系，探索区域HIV-1分子传播网络特征，为制定针对性的防控措施提供依据。方法:以2017-2018年嘉兴市新确证HIV/AIDS为研究对象，收集社会人口学、感染和传播等相关信息。采集血样并提取RNA，运用RT-PCR和巢式PCR扩增HIV-1的 pol区基因序列，采用Mega 6.0软件构建系统进化树进行HIV-1亚型分析。计算研究对象的HIV-1基因序列遗传距离，筛选构建分子传播网络的基因距离阈值，使用Cytoscape 3.6.0软件绘制分子传播网络。对基于分子传播网络的流行病学调查结果进行分析。 结果:研究对象HIV/AIDS 517例中，HIV-1基因序列包括15种基因亚型，以CRF01_AE（37.1%）、CRF07_BC（36.2%）和CRF08_BC（11.8%）为主。在1.0%的基因距离阈值下构建HIV-1分子传播网络，形成87个分子簇，总体入网率为45.8%（237/517）。多因素logistic回归分析结果显示，60~81岁年龄组（与14~24岁年龄组相比， OR=2.690，95% CI：1.058~6.844）、已婚（与未婚相比， OR=1.698，95% CI：1.003~2.875）、CRF07_BC亚型（与CRF01_AE亚型相比， OR=2.203，95% CI：1.426~3.404）的HIV-1分子成簇风险较高。分子传播网络中最大的CRF07_BC-1分子簇包括50例（2017年入网21例，2018年新增入网29例）HIV/AIDS，未婚（与已婚相比， OR=2.482，95% CI：1.140~5.402）、同性性传播（与异性性传播相比， OR=3.163，95% CI：1.543~6.483）、疑似高传播风险HIV/AIDS（与其他HIV/AIDS相比， OR=7.631，95% CI：1.783~32.654）、确证地在南湖区和平湖市［与其他区（县）相比， OR=2.225，95% CI：1.074~4.608］是进入最大簇的主要危险因素。该分子簇包含7例疑似高传播风险HIV/AIDS，均为同性性传播；自我报告首次发生男男性行为的时间范围为2010-2018年，确证前2年内的同性性伴数为20（ P 25， P 75：10，100）；其中6例自我报告有近期在南湖区某MSM交友活动场所寻找性伴活动史。 结论:2017-2018年嘉兴市新确证HIV/AIDS的HIV-1亚型多样，以散发为主，存在地理聚集性和一定数量的疑似高传播风险HIV/AIDS，呈快速传播现象，需开展针对性的强化干预。

abstractsObjective:To analyze the relationship between infection and transmission of HIV/AIDS, explore the characteristics of the HIV-1 transmission network, and provide evidence for formulating targeted prevention and control measures.Methods:The newly confirmed HIV/AIDS in Jiaxing from 2017 to 2018 were selected for the study. The sociodemographic and infection transmission-related information was gathered. The blood samples were collected and RNA was extracted, RT-PCR and nested PCR amplified the pol gene of HIV-1. The phylogenetic tree was constructed by Mega 6.0 software for subtype analysis. The genetic distance between strains was calculated, and the molecular transmission network was drawn by using Cytoscape 3.6.0 software. The results of the epidemiological study based on the molecular transmission network were analyzed. Results:There were fifteen HIV-1 gene subtypes in 517 cases of HIV/AIDS. The main subtypes were CRF01_AE (37.1%)、CRF07_BC (36.2%) and CRF08_BC (11.8%). Under the 1.0% gene distance threshold, 87 molecular clusters were established, and the total clustering rate was 45.8% (237/517). The cluster risk factors were 60-81 age group (compared with 14-24 age group, OR=2.690, 95% CI:1.058-6.844), married (compared with unmarried, OR=1.698, 95% CI:1.003-2.875), CRF07_BC subtype (compared with CRF01_AE, OR=2.203, 95% CI:1.426-3.404). The largest molecular cluster, CRF07_BC-1, consisted of 50 cases (including 21 cases confirmed in 2017 cases and 29 confirmed in 2018). Multivariate analysis showed that characteristics of unmarried (compared with married, OR=2.482, 95% CI:1.140-5.402), gays (compared with heterosexual, OR=3.163, 95% CI:1.543-6.483), cases with high-risk transmission (compared with other cases, OR=7.631, 95% CI:1.783-32.654), confirmed in Nanhu and Pinghu districts of Jiaxing (compared with other districts, OR=2.225, 95% CI:1.074-4.608) were risks for entering the largest molecular cluster. There were seven suspected high-risk transmission MSM in the largest molecular cluster. The first debut of homosexual behavior was from 2010 to 2018, and the median number of gay partners was 20 ( P 25, P 75：10, 100) within two years before being diagnosed. Six reported a recent history of looking for gay partners in an MSM dating place in Nanhu district. Conclusions:The HIV-1 subtypes of newly confirmed HIV/AIDS were diverse, mainly sporadic in Jiaxing from 2017 to 2018. There were geographical aggregation characteristics and suspected some high-risk transmission cases, suggesting that rapid transmission and targeted intensive intervention are needed.