CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

1024 Rapidly Changing Socio-Economic Patterns of HIV Incidence in Rural KwaZulu-Natal, South Africa Paul Mee 1 , Elphas Okango 2 , Hae-Young Kim 3 , Adrian Dobra 4 , Khai Hoan Tram 4 , Dickman Gareta 2 , Kobus Herbst 2 , Frank Tanser 5 1 University of Lincoln, Lincoln, United Kingdom, 2 Africa Health Research Institute, Mtubatuba, South Africa, 3 New York University, New York, NY, USA, 4 University of Washington, Seattle, WA, USA, 5 Stellenbosch University, Stellenbosch, South Africa Background: Despite a decline in HIV incidence in South Africa associated with the increased provision of HIV prevention services, there remains a lack of evidence on whether this progress has been experienced equitably by those most economically disadvantaged. We assessed whether the risk of acquiring HIV has changed over time for those in different socio-economic strata. Methods: The study used data from a population-based HIV testing platform run by the Africa Health Research Institute (AHRI) in KwaZulu-Natal, South Africa. Socio-economic status was derived using a Principal Components Analysis, with input variables representing asset ownership and services used. The households were stratified into three equal wealth quantiles in each year. Time to seroconversion was defined as the time between the first observation and the seroconversion date, randomly imputed between the dates of the last negative and positive HIV tests. Kaplan-Meier curves stratified by socio-economic strata were constructed using two open cohorts. For period 1 (2005 to 2014) the criteria for ART initiation was CD4 count <= 350 cells/ml. For period 2 (2015 to 2022) the criteria was CD4 count <= 500 cells/ml until 2016 and then ART initiation at any CD4 count starting in 2017. The p-value of a Mantel-Haenszel (MH) test was used to assess whether the trajectories of the curves differed significantly. A Cox PH model was developed to test statistical significance controlling for other covariates. seroconversion (MH p-value <= 0.001) and a higher incidence than those in the wealthiest strata (4.19/100 PY vs 3.13/100 PY). During the 2015 to 2022 period (N= 14594), there were 901 seroconversions recorded over 51485 PY (Fig B). The wealth trend had reversed with the least wealthy having a lower rate of seroconversion (MH p-value <= 0.001) and a lower incidence than those in the medium and wealthiest strata (1.37/100 PY vs 1.76/100 PY and 2.12/100 PY respectively). A Cox PH multivariate analysis controlling for age and sex confirmed these findings. Conclusion: This study provides clear evidence that dramatic changes have occurred over time in the association between wealth status and the risk of acquiring HIV, with those in the lowest wealth strata having the lowest seroconversion rate since the move towards universal ART. Results: During the 2005 to 2014 period (N=18,236) there were 2521 seroconversion events over 75086 person-years (PY) of observation (Fig A). Those in the least wealthy socio-economic strata had a higher rate of

those 15 years and above (0.82%) compared to children (0.48%). Of those with reactive results, 69 (43%) were confirmed HIV-positive and initiated ART as of January 9, 2024. The mode of transmission for 36 individuals (52%) was reported as reuse of contaminated needles and transfusion of blood/blood products for 13 (19%) individuals. Conclusion: HIV positivity in surrounding areas of Larkana is higher than national HIV prevalence (0.2%) suggesting ongoing community transmission. Both adults and children appear to be at risk of acquiring HIV from reuse of contaminated needles/syringes and unsafe blood. Actions need to be prioritized for identifying undiagnosed HIV and address unsafe injection and blood transfusion practices. 1023 Narrowing Disparities in HIV Incidence Between Males and Females in Rural KwaZulu-Natal South Africa Elphas Okango 1 , Paul Mee 2 , Khai Hoan Tram 3 , Hae-Young Kim 4 , Alex Edwards 5 , Dickman Gareta 1 , Maxime Inghels 2 , Kobus Herbst 1 , Henry Mwambi 6 , Adrian Dobra 3 , Frank Tanser 7 1 Africa Health Research Institute, Mtubatuba, South Africa, 2 Lincoln International Institute for Global Health, Lincoln, United Kingdom, 3 University of Washington, Seattle, WA, USA, 4 New York University Grossman School of Medicine, New York, NY, USA, 5 Emory University, Atlanta, GA, USA, 6 University of KwaZulu-Natal, Durban, South Africa, 7 Stellenbosch University, Cape Town, South Africa Background: The disproportionate HIV burden among women in Sub-Saharan Africa has been a concerning and complex public health issue. Several factors have contributed to this including biological vulnerability, gender inequality, transactional sex, and economic dependence. The past few years have seen concerted efforts to address this public health challenge including geared up universal testing and treatment. Methods: This study utilizes data from one of the world's largest HIV cohorts (Africa Health Research Institute (AHRI) population cohort) from rural South Africa that prospectively followed participants between 2005 and 2021. Poisson regression models were used to estimate the HIV incidence, incidence rates and confidence intervals. The outcome variable was seroconversion representing whether an individual tested positive or not over the observation period. Results: A total of 152,663 person-years with 3565 seroconversions were observed between 2005 and 2021. Our most recent data indicates a narrowing disparity in HIV incidence rates between males and females. The relative decrease in HIV incidence rates from 2014 to 2017 was 30.02% (from 3.92 to 2.74 per 100 person-years) among females and 38.91% (from 1.53 to 0.93 per 100 person-years) among males. In contrast, during the period from 2018 to 2021, there was a substantial decline of 43.08% (from 2.30 to 1.31 per 100 person-years) among females and 24.92% (from 0.78 to 0.58 per 100 person years) among males. In 2014, the female/male incidence ratio was 2.57 and this declined to 2.23 in 2021. HIV incidence for females increased with age from age 15 before reaching its peak at age 30 while in males it peaked at age 27. HIV incidence in females was higher across all ages (15-54) fig 1. Conclusion: Although massive strides have been made in lowering HIV incidence among both men and women, it is crucial to examine the plateauing reduction in HIV incidence among men to safeguard against any erosion of the advancements made thus far. The pace of HIV incidence reduction among women on the other hand underscores the effectiveness of intervention strategies and HIV programs. It is imperative to expand these strategies to further decrease HIV incidence among women.

Poster Abstracts

CROI 2024 328