Phylogenetic characteristics of HIV among female cross-border travelers in Yunnan province between 2003 and 2012.

ABSTRACT

Sexual transmission is currently the main mode of transmission of the human immunodeficiency virus (HIV). In this study, 181 HIV-infected female cross-border travelers entering Yunnan province were recruited between 2003 and 2012. HIV RNAs were extracted from their frozen serum and gag-pol gene sequences were obtained for phylogenetic and recombination analyses. In total, 131 gag-pol gene sequences were obtained successfully, at a rate of 72.4%. The most prevalent subtypes were CRF01_AE, followed by CRF08_BC, subtypes B and C. The other four subjects were classified as undefined subtypes and other recombinants. The subtype distribution of intravenous drug users was significantly different from that of sexually transmitted infections and unknown groups. The genetic distances of subtype B, C, and CRF01_AE strains were all close to the reference sequences from Yunnan province and Southeast Asian countries. Gene diversity and cocirculation of multiple subtypes were observed in female cross-border travelers, and CRF01_AE was the dominant epidemic subtype. The advantages of these subtype preferences for sexual transmission were obvious in HIV infection and transmission among this population. Our findings also suggest that close attention should be given to the HIV infection status of the female migrant population. In addition, a description of their epidemic characteristics is significant for the surveillance and prevention of acquired immunodeficiency syndrome in the Yunnan province.