Molecular epidemiology and transmission of HIV in Tianjin, 2015 / 中华流行病学杂志

ABSTRACT

Objective To understand the characteristics on the diversity of HIV subtypes and related transmission in Tianjin.Methods A total of 77 newly diagnosed ART-na(i)ve HIV infectors in 2015 were screened by CD4 +T cell counts ≥200 cells/μl.Viral RNAs were extracted from plasma samples.Reverse transcription PCR and nested PCR were used to analyze the amplification of pol and env gene fragments,sequencing,and related bioinformatics information.Results 46.03％ (29/63),30.16％ (19/63),11.11％ (7/63),4.76％ (3/63) and 7.94％ (5/63) of the individuals were infected under HIV subtypes CRF01_AE,CRF07_BC,B,CRF55_01B and URFs,with sexual transmission as the major mode of infection.CRF01_AE and CRF07_BC strains were predominant in both MSM and HST populations.The patterns of subtype distribution did not show statistical differences other than subtype B and CRF55_01B strain among HSTs.The proportion of CRFs increased significantly to 88.89％.8 new second-generation recombinant forms were identified the first time,including 3 CRF55_01B,2 AE/BC,1 AE/B and 1AE/B/C among MSMs and 1 AE/BC among HSTs.5.3％ of the NNRTI L100I HIV infectors transmitted the drug-resistant-mutation strain.3 linkages related to HIV transmission were confirmed through phylogenetic analysis with Bootstrap ≥98％ of pol and ≥80％of env.Conclusion The increasing complexity of HIV had been noticed in Tianjin,including the prevalence and transmission of second-generation recombinant and drug-resistant strains through different routes of transmission and in different regions.