Factors Associated with Unsuppressed Viral Loads Among Positive Partners Within HIV Sero-Discordant Couples and Population at Risk of Transmission. -A Population-based Survey in Malawi, Tanzania, Zambia and Eswatini

Introduction: Within-couple transmission among HIV sero-discordant couples make up a significant proportion of new HIV infections. Characteristics of sero-discordant couples associated with unsuppressed viral loads in the positive partner have been relatively underexplored. Our study aimed to identify individual and couple characteristics of serodiscordant couples associated with unsuppressed HIV viral loads and to estimate HIV negative partners at risk of being infected. Methods: This was a cross-sectional study using data from Population-based Impact Assessment (PHIA) survey conducted in four Sub-Saharan African countries, namely Malawi, Tanzania, Zambia and Eswatini between, October 2015 and June 2017. We used weighted logistic regression analysis to identify factors associated with the HIV positive partner being virally unsuppressed. Individual interview weights were applied to estimate the number of HIV negative partners at risk of acquiring an infection from their positive partners. Results: Of the 13,695 couples, 929(99.0%) were HIV sero-discordant and eligible for analysis. Among F-M+ couples, the odds of having unsuppressed viral loads was higher among HIV-positive male partners who were younger, between 25 to 34 years ( (Odds Ratio)OR-5.06 95% CI: 4.88-2.23), lived in urban regions(OR-1.28 95% CI: 1.26-1.31) and had not disclosed their HIV status to their partners(OR-4.46 95% CI:4.36-4.56). Among F+M- couples, the odds of being virally unsuppressed was higher in HIV positive females who were between the ages of 15 and 24(OR-2.24 95% CI:2.12-2.31) and had not disclosed their HIV status to their partners(OR-4.06 95% CI: 3.97-4.15); odds were lower among females if they lived in the urban areas(OR-0.93 95% CI 0.92-0.95). Both male and female HIV positive partners had higher odds of being unsuppressed if they had no formal education. An estimated 178,196 HIV-negative persons are at risk of acquiring HIV infection from their positive partners due to unsuppressed viral loads. Conclusions: Our study findings demonstrate that a significant proportion of people living with HIV in sero-discordant relationships are not virologically suppressed, with negative partners who are at risk of acquiring HIV. We recommend that Pre-Exposure prophylaxis (PrEP) be scaled up among negative partners in this high-risk population, to reduce the risk of HIV transmission. ABSTRACT Introduction: Within-couple transmission among HIV sero-discordant couples make up a significant proportion of new HIV infections. Characteristics of sero-discordant couples associated with unsuppressed viral loads in the positive partner have been relatively underexplored. Our study aimed to identify individual and couple characteristics of serodiscordant couples associated with unsuppressed HIV viral loads and to estimate HIV negative partners at risk of being infected. Methods: This was a cross-sectional study using data from Population-based Impact Assessment (PHIA) survey conducted in four Sub-Saharan African countries, namely Malawi, Tanzania, Zambia and Eswatini between, October 2015 and June 2017. We used weighted logistic regression analysis to identify factors associated with the HIV positive partner being virally unsuppressed. Individual interview weights were applied to estimate the number of HIV negative partners at risk of acquiring an infection from their positive partners. Results: Of the 13,695 couples, 929(99.0%) were HIV sero-discordant and eligible for analysis. Among F-M+ couples, the odds of having unsuppressed viral loads was higher among HIV-positive male partners who were younger, between 25 to 34 years ( (Odds Ratio)OR-5.06 95% CI: 4.88-2.23), lived in urban regions(OR-1.28 95% CI: 1.26-1.31) and had not disclosed their HIV status to their partners(OR-4.46 95% CI:4.36-4.56). Among F+M- couples, the odds of being virally unsuppressed was higher in HIV positive females who were between the ages of 15 and 24(OR-2.24 95% CI:2.12-2.31) and had not disclosed their HIV status to their partners(OR-4.06 95% CI: 3.97-4.15); odds were lower among females if they lived in the urban areas(OR-0.93 95% CI 0.92-0.95). Both male and female HIV positive partners had higher odds of being unsuppressed if they had no formal education. An estimated 178,196 HIV-negative persons are at risk of acquiring HIV infection from their positive partners due to unsuppressed viral loads. Conclusions: Our study findings demonstrate that a significant proportion of people living with HIV in sero-discordant relationships are not virologically suppressed, with negative partners who are at risk of acquiring HIV. We recommend that Pre-Exposure prophylaxis (PrEP) be scaled up among negative partners in this high-risk population, to reduce the risk of HIV transmission. having undetectable HIV viral load levels one cannot (47), positive levels Our study findings demonstrate how effective the various strategies implemented under the 90-90-90 campaign have been in combating the HIV epidemic. With almost all (99%) positive partners who were aware of their status on treatment, and subsequently a significant proportion achieving viral suppression, the need for increased screening to identify SDC couples is evident. With increased diagnoses, and thus, increased number of people aware of their HIV positive status, ART coverage can be increased in this population, and eventually a higher proportion people with suppressed viral loads. It is, therefore, important to develop and effect programs, as well as updating already existing programs that will not only focus on promoting ART use in identified positive partners of SDC couples, but meet the needs of negative partners in high- risk SDC partnerships, by expanding the use of PrEP, thereby, reducing the risk of acquiring the infection from their positive partners.