HIV-1 heterosexual transmission and association with sexually transmitted infections in the era of treatment as prevention

Objectives: HIV-1 heterosexual transmission among individuals on antiretroviral treatment (ART) with undetectable viremia is extremely rare. The aim of this study was to evaluate the risk of sexual HIV-1 transmission and other sexually transmitted infections (STIs) in HIV-1 serodifferent couples while the index partner is on ART. Methods: HIV transmission was evaluated in 200 HIV-1 heterosexual serodifferent couples in a stable relationship (≥3 months). All HIV-positive individuals had been on ART for ≥3 months and had been followed up for a median preceding time of 4.5 years (range 0.3–16 years) at the HIV couples clinic at Hospital Nossa Senhora da Conceição in Porto Alegre, Brazil. Following written informed consent, participants responded to demographic/behavioral questionnaires. Quantitative PCR for HIV RNA, T-cell subsets, and STI testing (syphilis, herpes, human papillomavirus, gonorrhea, and bacterial vaginosis) were performed. Self-collected vaginal swabs were obtained for quantitative HIV genital viral load testing. Results: Among 200 couples, 70% of index partners were female. Five seroconversions were observed; the HIV infection incidence was 2.5% (95% confidence interval 0.8% to 5.7%). Mean plasma viral load results were higher in HIV transmitters compared to non-transmitters (p = 0.02). The presence of STIs was significantly greater in couples who seroconverted (60.0% vs. 13.3%; odds ratio 9.75, 95% confidence interval 1.55–61.2; p = 0.023). The duration of undetectable HIV viremia and presence of STIs were associated with HIV transmission. Conclusions: Undetectable viremia was the main factor associated with non-transmissibility of HIV in this setting

Antiretroviral adherence and virologic suppression in partnered and unpartnered HIV-positive individuals in southern Brazil

Background: An undetectable serum HIV-1 load is key to effectiveness of antiretroviral (ARV) therapy, which depends on adherence to treatment. We evaluated factors possibly associated with ARV adherence and virologic response in HIV-infected heterosexual individuals. Methods: A cross-sectional study was conducted in 200 HIV-1 serodiscordant couples and 100 unpartnered individuals receiving ARV treatment at a tertiary hospital in southern Brazil. All subjects provided written informed consent, answered demographic/behavioral questionnaires through audio computer-assisted self-interviews (ACASI), and collected blood and vaginal samples for biological markers and assessment of sexually transmitted infections (STIs). HIV-negative partners were counseled and tested for HIV-1. Results: The study population mean age was 39.9 years, 53.6% were female, 62.5% were Caucasian, 52.6% had incomplete or complete elementary education, 63.1% resided in Porto Alegre. Demographic, behavioral and biological marker characteristics were similar between couples and single individuals. There was an association between adherence reported on ACASI and an undetectable serum viral load (P<0.0001). Logistic regression analysis demonstrated that single-tablet ARV-regimens were independently associated with adherence (OR = 2.3; 95CI%: 1.2–4.4; P = 0.011) after controlling for age, gender, education, marital status, personal income, ARV regimen, and median time of ARV use. A positive correlation between genital secretion PCR results and serum viral load was significant in the presence of STIs (r = 0.359; P = 0.017). Although HIV PCR detection in vaginal secretions was more frequent in women with detectable viremia (9/51, 17.6%), it was also present in 7 of 157 women with undetectable serum viral loads (4.5%), p = 0.005. Conclusions: ARV single tablet regimens are associated with adherence. Detectable HIV-1 may be present in the genital secretions of women with undetectable viremia which means there is potential for HIV transmission in adherent individuals with serologic suppression

Risk-Taking Behavior for HIV Acquisition during Pregnancy in Porto Alegre, Brazil

Recent studies suggest that acquisition of HIV-1 infection during pregnancy and breastfeeding is associated with a high risk of HIV mother-to-child transmission. This study evaluates risk factors associated with HIV acquisition during pregnancy in women delivering at a large metropolitan medical facility located in the south of Brazil. From February to August 2009, our group conducted a cross-sectional study assessing women’s risk for HIV acquisition by administering an oral survey to peripartum women. Of 2465 participants, 42% (n=1046) knew that partner had been tested for HIV. During pregnancy, 82% (n=2022) of participants never used condoms; yet 97% (n=2399) practiced vaginal sex. Multivariate logistic regression analysis showed that patients with more years of education, in a relationship for more than 1 year, and who knew their own HIV status were more likely to know their partners' HIV status (P<0.05). Those who were in relationship for more than 1 year and were married/living together were more likely to be comfortable discussing HIV testing with partners (P<0.05). In conclusion, women in Brazil are at risk of HIV-infection during pregnancy as they remain sexually active, often do not know their sexual partner’s HIV status, and have minimal condom use

The Effect of Partnership Presence and Support on HIV Viral Suppression Among Serodiscordant Partnered and Single Heterosexual HIV-Positive Individuals in Brazil

HIV-negative individuals in serodiscordant partnerships experience reduced risk of HIV acquisition when their partners adhere to ART and achieve undetectable viral loads. Partnership support may encourage ART adherence, reducing viral load and the risk of HIV transmission. This study aims to determine whether HIV viral suppression is associated with partnership status and partnership support among 201 HIV positive (HIV+ individuals in serodiscordant partnerships and 100 HIV+ unpartnered individuals receiving care at Hospital Nossa Senhora da Conceição in Porto Alegre, Brazil between 2014 and 2016. Clinical data and patient-reported questionnaire data were assessed, and propensity scores were used to control for confounding variables in adjusted logistic regression models. Viral suppression did not significantly differ between HIV+ partnered (78.5% virally suppressed) and unpartnered (76.0% virally suppressed) individuals. Among individuals in partnerships, viral suppression was significantly associated with having a partner who attended monthly clinic visits (AOR 2.99; 95% CI 1.00-8.93). Instrumental social support-attending monthly visits-may improve the odds of viral suppression among HIV+ individuals in serodiscordant relationships