Chronic inflammation with increased human immunodeficiency virus (HIV) RNAexpression in the vaginal epithelium of HIV-infected Thai women

Thai residents have a greater risk of heterosexual transmission of human im munodeficiency virus (HIV) than do US residents. To analyze host factors as sociated with heterosexual transmission, vaginal epithelial biopsies from H IV-seropositive Thai and US women were evaluated for tissue virus load and histologic makeup. In all, 84% of Thai and 14% of US women exhibited a chro nic inflammatory T cell infiltrate in the vaginal epithelium. In Thai tissu e, the infiltrate was associated with elevated levels of HIV RNA in the epi dermis. Uninfected Thai women also had vaginal epithelial inflammation. Inf lammation did not correlate with sexually transmitted diseases or HIV disea se stage. The higher rates and increased risk of heterosexual transmission in Thailand may be due to chronic inflammation at the site where the virus is transmitted, which leads to the accumulation of activated T cells. Such cells might act as targets for initial viral infection and subsequently as reservoirs that support efficient transmission.