北京市2018—2019年献血筛查发现的HIV-1毒株分子特征研究

目的 分析北京市献血者中筛查出的人类免疫缺陷病毒1型（human immunodeficiency virus type 1,HIV-1）感染者流行毒株及分子传播特征,为献血人群的艾滋病防治工作提供数据。方法 对2018—2019年献血筛查HIV-1阳性而报废的血液样本118份,针对病毒pol区部分片段进行基因扩增和测序,运用系统进化分析技术构建贝叶斯（Bayesian inference, BI）和最大似然（Maximum Likelihood, ML）系统进化树,确定HIV毒株亚型,并与从NCBI数据库下载来自中国各省份的23 823条HIV-1序列应用HyPhy2.2.4与Cytoscape3.7.2软件构建分子传播网络。结果 从收集HIV-1阳性报废血液样本成功获得pol区基因序列118条,系统进化分析显示,主要亚型为CRF01_AE 54份（占45.8%）和CRF07_BC 48份（占40.7%）。CRF01_AE中的Cluster 4和Cluster 5簇和CRF07_BC的MSM簇,所占比例分别为25.4%（30/118）、20.3%（24/118）和34.7%（41/118）。在0.5%基因距离阈值下,共有14条序列与数据库中序列发生关联;进入分子网络中HIV-1毒株亚型包括CRF01_AE（6例）、CRF07_BC（6例）、B（1例）和CRF67_01B（1例）。献血人群中的HIV感染者在分子网络中与12个省的HIV感染人群病毒序列相关联,重点关联的依次为来源于北京、上海、深圳三个大城市MSM人群的感染毒株。结论 北京市献血者筛查出的主要HIV-1流行毒株为CRF01_AE和CRF07_BC,在MSM人群占据优势的CRF01_AE Cluster 4、CRF01_AE Cluster 5和CRF07_BC MSM簇,在献血筛查HIV-1阳性人群中同样属于主要流行簇。分子网络分析未发现该人群中大规模的聚集性传播,进入分子网络的毒株主要与北京、上海、深圳三个大城市来源于MSM人群感染毒株相关联。提示强化献血人群健康教育,有效阻断有高危行为的MSM人群参与献血。

Molecular characteristics of HIV-1 strain found in blood donation screening in Beijing, 2018-2019

Objective To analyze the epidemic strains and molecular transmission characteristics of human immunodeficiency virus type 1 (HIV-1) infected individuals from blood donors in Beijing, and to provide data for AIDS prevention and control among blood donors. Methods On basis of the discarded HIV-1 positive blood samples from blood screening from 2018 to 2019, 118 samples were obtained. The pol gene fragment was amplified and sequenced, and the virus subtypes were identified based on the Bayesian inference (BI) and Maximum Likelihood (ML) trees through the MRBAYES and PhyML methods. The molecular transmission network was constructed by using HyPhy2.2.4 and Cytoscape3.7.2 software, combined with 23 823 HIV-1 sequences from all provinces in China from NCBI database. Results Totally 118 pol gene sequences were successfully obtained from the collected HIV-1 positive discarded blood samples, and CRF01_AE (54,45.8%) and CRF07_BC (48,40.7%) were the major subtypes. Phylogenetic analysis showed that the proportion of Cluster 4 and Cluster 5 in CRF01_AE and cluster MSM in CRF07_BC was 25.4% (30/118), 20.3% (24/118) and 34.7% (41/118), respectively, which were the main epidemic clusters of MSM transmission in China. HIV-1 molecular transmission network was constructed under the threshold of 0.5% optimal gene distance, and a total of 14 sequences were connected to the sequences from NCBI; the subtypes included CRF01_AE(6 cases), CRF07_BC(6), B(1) and CRF67_01B(1). The network access sequences were highly correlated with HIV-1 infected people in 12 provinces, and the key related cities included Beijing, Shanghai and Shenzhen.Conclusions CRF01_AE and CRF07_BC were the main epidemic strain detected by blood donation in Beijing. Among them, CRF01_AE Cluster 4, CRF01_AE Cluster 5 and CRF07_BC MSM, which are the mainly dominant in MSM population, were also the main epidemic clusters among blood donors. No recent large-scale aggregated transmission has been found in molecular network analysis, the strains entering the molecular network are mainly associated with HIV infected people from MSM populations in Beijing, Shanghai and Shenzhen. Health education for blood donors should be strengthened to effectively block MSM with high-risk behavior from participating in blood donation.