Phylodynamic analysis reveals changing transmission dynamics of HIV-1 CRF01_AE in Japan from heterosexuals to men who have sex with men

Machiko Otani; Teiichiro Shiino; Makiko Kondo; Atsuko Hachiya; Masako Nishizawa; Tadashi Kikuchi; Tetsuro Matano; Japanese Drug Resistance HIV-1 Surveillance Network

doi:10.1016/j.ijid.2021.05.066

Phylodynamic analysis reveals changing transmission dynamics of HIV-1 CRF01_AE in Japan from heterosexuals to men who have sex with men

Int J Infect Dis. 2021 Jul:108:397-405. doi: 10.1016/j.ijid.2021.05.066. Epub 2021 Jun 1.

Authors

Machiko Otani¹, Teiichiro Shiino², Makiko Kondo³, Atsuko Hachiya⁴, Masako Nishizawa⁵, Tadashi Kikuchi⁶, Tetsuro Matano⁷; Japanese Drug Resistance HIV-1 Surveillance Network

Affiliations

¹ AIDS Research Centre, National Institute of Infectious Diseases, Tokyo, Japan; The Institute of Medical Science, University of Tokyo, Tokyo, Japan. Electronic address: minoue@niid.go.jp.
² 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. Electronic address: tshiino@hosp.ncgm.go.jp.
³ Division of Microbiology, Kanagawa Prefectural Institute of Public Health, Kanagawa, Japan. Electronic address: kondo.xp86@pref.kanagawa.jp.
⁴ Clinical Research Centre, National Hospital Organization Nagoya Medical Centre, Aichi, Japan; Tokyo Medical University and Nitobe Bunka College, Tokyo, Japan. Electronic address: m_hachiy@tokyo-med.ac.jp.
⁵ AIDS Research Centre, National Institute of Infectious Diseases, Tokyo, Japan. Electronic address: ncmasako@nih.go.jp.
⁶ AIDS Research Centre, National Institute of Infectious Diseases, Tokyo, Japan. Electronic address: kik248@niid.go.jp.
⁷ AIDS Research Centre, National Institute of Infectious Diseases, Tokyo, Japan; The Institute of Medical Science, University of Tokyo, Tokyo, Japan. Electronic address: tmatano@nih.go.jp.

PMID: 34082091
DOI: 10.1016/j.ijid.2021.05.066

Abstract

Background: 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.

Methods: 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.

Results: 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.

Conclusions: 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.

Keywords: AIDS; Cluster analysis; HIV-1; Japan; Men who have sex with men; Molecular epidemiology.

MeSH terms

China
HIV Infections* / epidemiology
HIV-1* / genetics
Heterosexuality
Homosexuality, Male
Humans
Japan / epidemiology
Male
Phylogeny
Sexual and Gender Minorities*