AIDS Research Centre, National Institute of Infectious Diseases, Tokyo, Japan; The Institute of Medical Science, University of Tokyo, Tokyo, Japan.
AIDS Research Centre, National Institute of Infectious Diseases, Tokyo, Japan; Department of Data Science, Centre for Clinical Sciences, National Centre for Global Health and Medicine, Tokyo, Japan.
Int J Infect Dis. 2021 Jul;108:397-405. doi: 10.1016/j.ijid.2021.05.066. Epub 2021 Jun 1.
HIV-1 circulating recombinant form (CRF) 01_AE is the second major subtype in Japan. Our previous study indicated that CRF01_AE was predominantly circulating in heterosexuals/injecting drug users (IDUs). With implications of increased CRF01_AE infections among men who have sex with men (MSM), this study sought to investigate whether the transmission dynamics of CRF01_AE infections in Japan have changed.
Sequences from 8032 newly diagnosed HIV-1-infected individuals were analysed. For 614 (7.6%) of CRF01_AE cases, clusters were identified and categorised by transmission risks. Median times to the most recent common ancestors (tMRCA) were estimated.
The individuals were predominantly Japanese (64%) and male (72%). MSM became the predominant transmission risk from 2014. Thirty transmission clusters (TCs) and 48 pairs, including 40% of individuals, were identified. MSM were approximately five times more likely to be in a TC compared to heterosexuals, and were the major contributors to TCs. tMRCA data suggest that MSM TCs emerged from 1996 and became predominant around 2000.
CRF01_AE has spread among MSM, with frequent and continuous cluster formations, and MSM has become the predominant transmission risk. Our study suggested that CRF01_AE transmission has shifted from heterosexuals/IDUs to MSM. Prevention measures targeting key populations should be considered for controlling CRF01_AE spread.
HIV-1 循环重组形式（CRF）01_AE 是日本的第二大亚型。我们之前的研究表明，CRF01_AE 主要在异性恋者/注射吸毒者（IDU）中传播。由于男男性接触者（MSM）中 CRF01_AE 感染的增加，本研究旨在调查日本 CRF01_AE 感染的传播动态是否发生了变化。
对 8032 名新诊断的 HIV-1 感染个体的序列进行了分析。对于 614 例（7.6%）CRF01_AE 病例，根据传播风险确定了聚类并进行了分类。估计了最近共同祖先（tMRCA）的中位数时间。
这些个体主要是日本人（64%）和男性（72%）。MSM 从 2014 年开始成为主要的传播风险。确定了 30 个传播簇（TC）和 48 对，包括 40%的个体。与异性恋者相比，MSM 更有可能处于 TC 中，并且是 TC 的主要贡献者。tMRCA 数据表明，MSM TC 于 1996 年出现，并于 2000 年左右成为主要传播方式。
CRF01_AE 在 MSM 中传播，频繁且持续地形成簇，MSM 已成为主要的传播风险。我们的研究表明，CRF01_AE 的传播已经从异性恋者/IDU 转移到了 MSM。应该考虑针对重点人群的预防措施来控制 CRF01_AE 的传播。
