Study On The Main Factors Of HIV Transmission Among Sero-discordant Couples And A Bernoulli Process Model To Model Its Transmission

BackgroundHIV transmission between HIV sero-discordant couples has become one of the main transmission modes. It’s important meaningful to understand sexual behavior changes among HIV sero-discordant couples before and after knowing their HIV infection and explore the main factors influencing the spouse seroconversion. It provide a scientific basis to take related measures to prevent HIV transmission among HIV sero-discorant couples.Objectives1. To describe sexual behavior changes among HIV sero-discordant couples before and after knowing their HIV infection.2. To explore the main factors influencing the negative spouse seroconversion among HIV sero-discordant couples.3. Bernoulli process model to model the effect of intervention measures on prevention HIV transmission among HIV sero-discordant couples.MethodsA cross-sectional study was conducted among150newly identified HIV sero-discordant couples or HIV sero-concordant couples between January1,2011and December31,2012. These couples were interviewed to acquire information of their sexual behavior changes before and after knowing their HIV infection.A1:2matched nested case-control study was implemented to explore the main factors influencing the negative spouse seroconversion among HIV sero-discordant couples. The case group were from those spouse seroconversion couples between January1,2011to December31,2012and the control group were from HIV sero-discordant couples according to the same gender and age as the case group. According to the main factors model intervention strategies and measures on reduction HIV transmission among sero-discordant couples.Results1. Of the150HIV newly identified couples,72of them were sero-concordant couples and78of them were sero-discordant couples.86.0%of index cases had never used condom before their diagnosis of HIV infection. After diagnosis of HIV infection, the proportion of consistent condom use increased from11.5%to86.5%among the HIV sero-discordant couples but from 16.7%to44.1%among the HIV sero-concordant couples. The proportion of sexual behaviors reduction among these couples was64.7%.2. The factors associated with the index case’s partner HIV positive included having history of have casual sexual partners(OR=12.85,95%CI:4.84-34.10) and having history of have commercial sexual partners(OR=8.39.95%CI:0.88-80.20).3. The HIV incidence of sero-discordant couples was1.02(95%CI:0.76-1.33) per100person-years from2011to2012. Multivariate conditional logistic regression analysis showed that reproductive demand, antiretroviral treatment and consistent condom use were the main factor influencing the negative spouse seroconversion among HIV sero-discordant couples. Of these factors, reproductive demand (OR=5.18,95%CI:1.19-22.58) was the risk factor and ART(OR=0.09,95%CI:0.01-0.67) and consistent condom use (OR=0.05,95%Cl:0.01-0.28) were the protective factors of avoiding spouse seroconversion.4. According to the results of multivariate conditional logistic regression analysis. Modeling consistent condom use and antiretroviral treatment results show that, with the coverage of antiretroviral treatment is90%, if the proportion of consistent condom use increased from50%to90%. then it can reduce80.7%of the risk of spouse seroconversion.In another situation, with the proportion of consistent condom use is90%, if the coverage of antiretroviral treatment increased from50%to90%. then it can reduce64.5%of the risk of spouse seroconversion.ConclusionsHalf of spouses were HIV positive while the index case was first diagnosed. After diagnosis of HIV infection and spouse notification. Risk sexual behavior reduce significantly among the HIV sero-discordant couples. So, it’s important for early diagnosis and early spouse notification to reduce the risk of HIV transmission among HIV sero-discordant couples. Conception and reproductive demand of sero-discordant couples was the important risk factor. It needs to develop and guide safer conception intervention methods for these HIV affected couples. Consistent condom use is the most effective measure of preventing heterosexual transmission between spouses. HIV positive index spouses receiving timely antiretroviral therapy can greatly reduce the risk of sexual transmission among sero-discordant couples. So, it should promote these index spouses to receive antiviral therapy as soon as possible.