Characteristics of HIV-1 Molecular Transmission Networks and Drug Resistance Among Men Who Have Sex with Men in Tianjin, China (2014-2018)

Abstract

BackgroundIn Tianjin, China, there is a relatively high prevalence of HIV in men who have sex with men (MSM). The number of cases of HIV in Tianjin is also increasing. We investigated the HIV molecular transmission network, genetic tropisms, and drug resistance mutations in Tianjin. MethodsBlood samples were collected from 510 newly diagnosed antiretroviral therapy (ART)-naïve HIV-1-infected subjects among MSM in Tianjin. Partial pol and env genes were sequenced and used for phylogenetic, genetic tropism, and genotypic drug resistance analyses. Molecular clusters were identified with 1.5% genetic distance and 90% bootstrap support.ResultsAmong the 436 HIV-1 pol sequences obtained from the study participants, various genotypes were identified, including CRF01_AE (56.9%), CRF07_BC (27.8%), B (7.3%), CRF55_01B (4.1%), unique recombinant forms (URFs) (3.7%), and CRF59_01B (0.2%). A higher prevalence of X4 viruses was observed in individuals infected with CRF55_01B (56.3%) and CRF01_AE (46.2%) than with other subtypes. Of all 110 sequences in the 36 clusters, 62 (56.4%) were observed in 23 CRF01_AE clusters and 18 (16.4%) in four CRF07_BC clusters. Nine sequences clustered with at least one other shared the same drug resistance mutation (DRM). In different cluster sizes, the distributions of individuals by age, presence of sexually transmitted disease, and presence of DRMs, were significantly different. ConclusionWe revealed the characteristics of HIV molecular transmission, tropism, and DRMs of ART-naïve HIV-infected individuals among the MSM population in Tianjin. Identifying infected persons at risk of transmission is necessary for proposing counseling and treating these patients to reduce the risk of HIV transmission.

Practice and Prospect: HIV-1 Molecular Network-Based Studies in China

“…Therefore, identifying individuals with high transmission risk through molecular networks is important for establishing targeted interventions and contributes to the rational allocation of public health resources. Studies from Dehong (Yunnan Province) 66 and Guangzhou (Guangdong Province) 67 emphasized the role the high-risk infected individuals played in the formation of the molecular network. A targeted intervention can subsequently effectively contain HIV transmission.…”