The prevalence and dynamics of human immunodeficiency virus-1 subtypes among men who have sex with men in Beijing / 中华传染病杂志

ABSTRACT

Objective To investigate the subtype distribution and changing trend of human immunodeficiency virus (HIV)-1 strains among men who have sex with men (MSM) during 2005-2011 in Beijing.Methods Five serial cross-sectional surveys of MSM were conducted in the year of 2005-2006,2007,2008,2009,and 2010-2011 in Chaoyang district of Beijing.Whole blood samples were collected and then RNA was extracted.HIV-1 gag gene was characterized by reverse transcriptase and nested polymerase chain reaction (RT-PCR) amplification,DNA sequencing,and phylogenetic analysis of viral sequences to determine the HIV-1 subtypes.Results Phylogenetic analysis of the sequences revealed that the predominant subtypes of HIV-1 gag gene included subtype B,CRF01_AE and CRF07_BC.And CRF15_01B was detected from the year of 2008.In addition,significant changes of the distributions of subtypes and CRFs occurred from 2005 to 2011 in HIV+ MSM.Subtype B showed a significant decreased trend,while the proportions of CRF01 _AE and CRF07_BC significantly increased in the 7-year period,particularly that of CRF01_AE.Conclusions The substantial changes are observed in the diversity of HIV-1 strains circulating among MSM in Beijing during a 7-year period.