ABSTRACT
<p><b>OBJECTIVE</b>To understand the efficacy of antiviral therapy on prevention of HIV transmission and to assess the feasibility of treatment-as-prevention strategy in public health practice, among sero-discordant couples in Guangxi Zhuang autonomous region (Guangxi).</p><p><b>METHODS</b>Data was gathered through the AIDS prevention and control information system in Guangxi from January 1, 2008 to December 31, 2014, on HIV sero-discordant couples. Time-dependent Cox Model was used to analyze the efficacy of antiviral treatment.</p><p><b>RESULTS</b>A total of 7 694 sero-discordant couples were followed and 394 appeared positive from those negative spouses. The overall HIV positive seroconversion rate was 2.5 (2.2-2.7) /100 person-year. The HIV positive sero-conversion rates were 4.3 (3.7-4.8) /100 person-year in the untreated cohort and 1.6 (1.4-1.9) per 100 person-year in the treated cohort. Rate of HIV transmission declined by 51% in the treated cohort (HR=0.49, 95%CI: 0.40-0.60) but appeared as 45% (AHR=0.55, 95%CI:0.43-0.69) after adjusting for factors as sex, age, education, marital status, occupation, transmission route and baseline CD4(+)T lymphocyte cell count. The rate of reduction in transmission was significant among couples in which the HIV-positive spouses showing the following features as: aged ≥25 years, married, farmers, with educational level of junior high school or below, baseline CD4(+)T lymphocyte cell count <500 cells/mm(3) and infection was through heterosexual intercourse.</p><p><b>CONCLUSION</b>Antiviral therapy as a prevention strategy among sero-discordant couples seemed feasible and effective in Guangxi. Expansion of the coverage on antiviral therapy would reduce the spread of HIV in married couples.</p>