Temporal and spatial monitoring of HIV prevalence and incidence rates using geospatial models: Results from South African women

Understanding the impact of women's correct risk perception on human immunodeficiency virus diagnosis: Insights from South Africa

BACKGROUND

South African women have the highest burden of HIV infections globally. We investigated the temporal trends and the impact of key factors associated with HIV diagnosis among a nationally representative cohort of South African women.

METHODS

Total of 24,657 women who participated in the National HIV, Behaviour and Health Surveys conducted from 2002-to-2017.

RESULTS

Despite decades-long prevention efforts, we observed a significant increase in HIV prevalence over time (22% in 2002 to 21% in 2005-2008 and 29% in 2012-2017). Overall, 46% of the women living with HIV were not aware of their risk of HIV with age-specific disparities. Our findings revealed compelling evidence between HIV seropositivity and high HIV risk-perception (adjusted Odds Ratio (aOR):1.47 to 3.29) which increased overtime and exceeded the other factors. At a population-level, 45% of the HIV diagnoses were exclusively associated with women who believed they were at risk of HIV in 2012-2017. Women who reported using condoms at last sexual act were also at increased risk of HIV infection, with a population attributable risk of 18% (2002) to 21% (2012-2017).

CONCLUSION

There is an urgent need for culturally, socially, and linguistically appropriate prevention and awareness campaigns with realistic, non-confrontational messages.

Exploring Determinants of HIV/AIDS Self-Testing Uptake in South Africa Using Generalised Linear Poisson and Geographically Weighted Poisson Regression

Increased HIV/AIDS testing is of paramount importance in controlling the HIV/AIDS pandemic and subsequently saving lives. Despite progress in HIV/AIDS testing programmes, most people are still reluctant to test and thus are still unaware of their status. Understanding the factors associated with uptake levels of HIV/AIDS self-testing requires knowledge of people's perceptions and attitudes, thus informing evidence-based decision making. Using the South African National HIV Prevalence, HIV Incidence, Behaviour and Communication Survey of 2017 (SABSSM V), this study assessed the efficacy of Generalised Linear Poisson Regression (GLPR) and Geographically Weighted Poisson Regression (GWPR) in modelling the spatial dependence and non-stationary relationships of HIV/AIDS self-testing uptake and covariates. The models were calibrated at the district level across South Africa. Results showed a slightly better performance of GWPR (pseudo R² = 0.91 and AICc = 390) compared to GLPR (pseudo R² = 0.88 and AICc = 2552). Estimates of local intercepts derived from GWPR exhibited differences in HIV/AIDS self-testing uptake. Overall, the output of this study displays interesting findings on the levels of spatial heterogeneity of factors associated with HIV/AIDS self-testing uptake across South Africa, which calls for district-specific policies to increase awareness of the need for HIV/AIDS self-testing.

Geospatial variations in socioeconomic conditions and health outcomes in COVID-19 era: insights from South Africa (2020-2022)

South Africa also has the highest burden of coronavirus disease 2019 (COVID-19) related comorbidities in Africa. We aimed to quantify the temporal and geospatial changes in unemployment, food insecurity, and their combined impact on depressive symptoms among South Africans who participated into several rounds of national surveys. We estimated the population-attributable risk percent (P A R % ) for the combinations of the risk factors after accounting for their correlation structure in multifactorial setting. Our study provided compelling evidence for immediate and severe effect of the pandemic where 60% of South Africans reported household food insecurity or household hunger, shortly after the pandemic emerged in 2020. Despite the grants provided by the government, these factors were also identified as the most influential risk factors (adjusted odds ratios (aORs) ranged from 2.06 to 3.10, p < 0.001) for depressive symptoms and collectively associated with 62% and 53% of the mental health symptoms in men and women, respectively. Similar pattern was observed among pregnant women and 41% of the depressive symptoms were exclusively associated with those who reported household hunger. However, aORs associated with the concerns around pandemic and vaccine were mostly not significant and ranged from 1.12 to 1.26 which resulted substantially lower impacts on depressive symptoms (PAR%:7%-and-14%). Our findings suggest that South Africa still has unacceptably high rates of hunger which is accelerated during the pandemic. These results may have significant clinical and epidemiological implications and may also bring partial explanation for the low vaccine coverage in the country, as priorities and concerns are skewed towards economic concerns and food insecurity.

Population-level impact of beliefs and attitudes on vaccine decision-making in South Africa: results from the COVID-19 Vaccine Survey (2021/2022)

OBJECTIVES

In addition to being home to more than seven million HIV-infected individuals, South Africa also has a high burden of COVID-19 and related comorbidities worldwide. We aimed to identify the most influential "beliefs" and "attitudes" on vaccine decision-making behavior.

STUDY DESIGN

This study used panel data from cross-sectional surveys.

METHODS

We used the data from Black South Africans who participated in the "COVID-19 Vaccine Surveys" (November 2021 and February/March 2022) in South Africa. Besides standard risk factor analysis, such as multivariable logistic regression models, we also used the modified version of population attributable risk percent and estimated the population-level impacts of beliefs and attitudes on vaccine decision-making behavior using the methodology in multifactorial setting.

RESULTS

A total of 1399 people (57% men and 43% women) who participated in both surveys were analyzed. Of these, 336 (24%) reported being vaccinated in survey 2. Overall low perceived risk, concerns around efficacy, and safety were identified as the most influential factors and associated with 52%-72% (<40 years) and 34%-55% (40+ years) of the unvaccinated individuals.

CONCLUSION

Our findings highlighted the most influential beliefs and attitudes on vaccine decision-making and their population-level impacts, which are likely to have significant public health implications exclusively for this population.

Impact of recurrent sexually transmitted infections on HIV seroconversion: Results from multi-state frailty models

After several decades of research, South Africa is still considered to be the epicentre of HIV epidemic. The country also has the highest burden of sexually transmitted infections (STIs) which have been frequently linked to increasing rates of HIV transmission due to biological and behavioural associations between these two pathogeneses. We investigated the cumulative impact of recurrent STIs on subsequent HIV seroconversion among a cohort of South African women. We used the 'frailty' models which can account for the heterogeneity due to the recurrent STIs in a longitudinal setting. The lowest HIV incidence rate was 5.0/100 person-year among women who had no baseline STI and remained negative during the follow-up. This estimate was three times higher among those who had recurrent STIs in the follow-up period regardless of their STI status at baseline (15.8 and 14.0/100 person-year for women with and without STI diagnosis at baseline, respectively). Besides younger age and certain partnership characteristics, our data provided compelling evidence for the impact of recurrent STI. diagnoses on increasing rates of HIV. At the population-level, 65% of HIV infections collectively associated with recurrent STIs. These results have significant clinical and epidemiological implications and may play critical role in the trajectory of the infections in the region.