天津市男男性行为人群HIV感染者毒株亚型和成簇特点

目的 了解我市男男性行为人群（men who have sex with men，MSM）人免疫缺陷病毒（human immunodeficiency virus，HIV）感染者毒株的亚型分布和成簇特点。方法 收集2013-2017年MSM随访研究中新发现和队列中阳转的未经抗逆转录病毒治疗（antiretroviral therapy，ART）的HIV感染者血浆样本，经RNA提取和扩增，共获得100份pol区序列，进行基因型、耐药突变和分子进化分析，并与人口学和行为学资料相结合分析其成簇特点。结果 HIV感染者流行的亚型依次为CRF01_AE占60.0%（60/100），CRF07_BC占28.0%（28/100），B亚型占6.0%（6/100），CRF55_01B亚型占4.0%（4/100），其他独特型二代重组亚型占2.0%（2/100）。传播性耐药（transmitted drug resistance，TDR）流行率为7%（7/100），其中不同亚型的流行率依次为B亚型3.0%（3/100）、CRF01_AE 2.0%（2/100）、CRF07_BC 1.0%（1/100）和CRF55_01B 1.0%（1/100）。耐药突变以NNRTIs突变为主，占4.0%（4/100），其次为NRTIs突变占2.0%（2/100），PIs突变占1%（1/100）。成簇样本占31.0%（31/100），共分布在13个传播簇内，成簇和非成簇的感染者的亚型、户籍和性病史差异均有统计学意义（均有P<0.05）。结论 天津市MSM感染者中HIV毒株亚型分布情况日趋复杂，新型重组和耐药毒株不断出现并传播，应引起高度重视。

Analysis on the Characteristics of HIV genetic diversity and clusters among MSMs in Tianjin

Objective To understand the genetic diversity and characteristics of clusters of HIV strains among MSMs in Tianjin. Methods Pol gene fragments were obtained from 100 newly discovered and transformed HIV-positive HIV-infected antiretro viral therapy (ART) -naïve MSM who visited a retrospective cohort study of MSMs from June 2013 to June 2017 in Tianjin, by viral plasma RNA extraction and amplification. Genetic, drug-resistance and phylogenetic analyses were used to evaluate the characteristics of HIV molecular clusters combined with patient demographic and behavioral characteristics within the context of the entire cohort. Results 60.0% (60/100), 28.0% (28/100), 6.0% (6/100), 4.0% (4100) and 2.0% (2/100) of the individuals were infected under HIV subtypes CRF01_AE, CRF07_BC, B, CRF55_01B and URFs. 7. 0% (7/100) of infectors had transmitted drug-resistance mutations. The TDR prevalence rates of different subtypes were 3.0% (3/100) of subtype B, 2.0% (2/100) of CRF01_AE, 1.0% (1/100) of CRF07_BC and 1.0% (1/100) of CRF55_01B. TDRs was predominantly towards NNRTIs 4.0% (4/100). In contrast, TDR to NRTIs and PIs were 2.0% (2/100) and 1.0% (1/100) respectively. We identified 13 transmission clusters including 31 infectors. There were statistically significant differences in subtype, registration and history of sexually transmitted diseases between clustered and non-clustered infected people (P<0.050). Conclusions Results from this study suggested that the prevalence trends of HIV-1 CRFs, URFs and TDR strains among MSM were not optimistic. More attentions should be paid for prevention and control of HIV epidemic in Tianjin.