Molecular epidemiological characteristics of HIV-1 among young men who have sex with men (MSM) in Hangzhou, 2022–2024
Abstract
ObjectiveTo characterize HIV-1 subtype distribution, transmission clustering, and associated demographic and temporal risk factors among newly diagnosed young men who have sex with men (MSM) aged <30 years in Hangzhou (2022–2024), comparing student and non-student subgroups.MethodsPol sequences from 857 newly diagnosed, ART-naive young MSM underwent phylogenetic, molecular transmission network, and Bayesian evolutionary analyses; intergroup differences were assessed with chi-square or Fisher’s exact tests and logistic regression.ResultsTwelve subtypes/CRFs were identified, with CRF07_BC (46.67%) and CRF01_AE (35.82%) dominant. At a 1.0% genetic distance, 249 of 857 cases (29.05%) formed 81 clusters; 62 suspected high-transmission-risk cases were predominantly CRF01_AE (54.84%). Both largest clusters were CRF01_AE, with posterior median Re above 1 in 2024 but wide 95% HPDs that included values below 1. Clustering risk was higher among cases registered elsewhere in Zhejiang Province (OR = 1.523, 95% CI: 1.041–2.230) and in the 20–24 years group (OR = 1.501, 95% CI: 1.094–2.061). This age group was also more likely to be classified as suspected high-transmission-risk cases (OR = 2.994, 95% CI: 1.483–6.047), as were cases with CRF01_AE infection relative to others/URFs (OR = 3.471, 95% CI: 1.271–9.479). Household registration in other cities of Zhejiang Province was associated with increased odds of others/URFs relative to CRF01_AE infection (OR = 1.837, 95% CI: 1.130–2.986, p = 0.014), compared with household registration outside Zhejiang Province. Student status was not observed to be associated with clustering or high-transmission-risk classification.ConclusionHangzhou’s young-MSM epidemic is genetically diverse; two CRF01_AE clusters sustained transmission risk (posterior median Re > 1 in 2024) after 3–6 years of local circulation. Prevention should target the broader young MSM population, not students alone.
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BibTeX
@article{hu2026molecular,
title = {{Molecular epidemiological characteristics of HIV-1 among young men who have sex with men (MSM) in Hangzhou, 2022–2024}},
author = {Yongfang Hu and Ke Xu and Xianglian Lv and Xingliang Zhang and Zhou Sun and Jun Shou and Qin Fan and Jiafeng Zhang and Xiangjie Meng},
journal = {Frontiers in Public Health},
year = {2026},
month = nov,
doi = {10.3389/fpubh.2026.1998225},
url = {https://www.frontiersin.org/articles/10.3389/fpubh.2026.1998225},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Molecular epidemiological characteristics of HIV-1 among young men who have sex with men (MSM) in Hangzhou, 2022–2024
AU - Yongfang Hu
AU - Ke Xu
AU - Xianglian Lv
AU - Xingliang Zhang
AU - Zhou Sun
AU - Jun Shou
AU - Qin Fan
AU - Jiafeng Zhang
AU - Xiangjie Meng
PY - 2026
DA - 2026/11/06
JO - Frontiers in Public Health
DO - 10.3389/fpubh.2026.1998225
UR - https://www.frontiersin.org/articles/10.3389/fpubh.2026.1998225
AB - ObjectiveTo characterize HIV-1 subtype distribution, transmission clustering, and associated demographic and temporal risk factors among newly diagnosed young men who have sex with men (MSM) aged <30 years in Hangzhou (2022–2024), comparing student and non-student subgroups.MethodsPol sequences from 857 newly diagnosed, ART-naive young MSM underwent phylogenetic, molecular transmission network, and Bayesian evolutionary analyses; intergroup differences were assessed with chi-square or Fisher’s exact tests and logistic regression.ResultsTwelve subtypes/CRFs were identified, with CRF07_BC (46.67%) and CRF01_AE (35.82%) dominant. At a 1.0% genetic distance, 249 of 857 cases (29.05%) formed 81 clusters; 62 suspected high-transmission-risk cases were predominantly CRF01_AE (54.84%). Both largest clusters were CRF01_AE, with posterior median Re above 1 in 2024 but wide 95% HPDs that included values below 1. Clustering risk was higher among cases registered elsewhere in Zhejiang Province (OR = 1.523, 95% CI: 1.041–2.230) and in the 20–24 years group (OR = 1.501, 95% CI: 1.094–2.061). This age group was also more likely to be classified as suspected high-transmission-risk cases (OR = 2.994, 95% CI: 1.483–6.047), as were cases with CRF01_AE infection relative to others/URFs (OR = 3.471, 95% CI: 1.271–9.479). Household registration in other cities of Zhejiang Province was associated with increased odds of others/URFs relative to CRF01_AE infection (OR = 1.837, 95% CI: 1.130–2.986, p = 0.014), compared with household registration outside Zhejiang Province. Student status was not observed to be associated with clustering or high-transmission-risk classification.ConclusionHangzhou’s young-MSM epidemic is genetically diverse; two CRF01_AE clusters sustained transmission risk (posterior median Re > 1 in 2024) after 3–6 years of local circulation. Prevention should target the broader young MSM population, not students alone.
SN - 2296-2565
ER -