Potential Impact and Cost-Effectiveness of Condomless-Sex-Concentrated PrEP in KwaZulu-Natal Accounting for Drug Resistance.

INTRODUCTION: Oral preexposure prophylaxis (PrEP) in the form of tenofovir-disoproxil-fumarate/emtricitabine is being implemented in selected sites in South Africa. Addressing outstanding questions on PrEP cost-effectiveness can inform further implementation. METHODS: We calibrated an individual-based model to KwaZulu-Natal to predict the impact and cost-effectiveness of PrEP, with use concentrated in periods of condomless sex, accounting for effects on drug resistance. We consider (1) PrEP availability for adolescent girls and young women aged 15-24 years and female sex workers, and (2) availability for everyone aged 15-64 years. Our primary analysis represents a level of PrEP use hypothesized to be attainable by future PrEP programs. RESULTS: In the context of PrEP use in adults aged 15-64 years, there was a predicted 33% reduction in incidence and 36% reduction in women aged 15-24 years. PrEP was cost-effective, including in a range of sensitivity analyses, although with substantially reduced (cost) effectiveness under a policy of ART initiation with efavirenz- rather than dolutegravir-based regimens due to PrEP undermining ART effectiveness by increasing HIV drug resistance. CONCLUSIONS: PrEP use concentrated during time periods of condomless sex has the potential to substantively impact HIV incidence and be cost-effective.

Antiretroviral Treatment and Sexual Risk Behavior in South Africa.

The sexual behavior of individuals living with HIV determines the onward transmission of HIV. With the understanding that antiretroviral therapy (ART) prevents transmission of HIV, the sexual behaviors of the individuals not on ART with unsuppressed viral loads becomes of the greatest importance in elucidating transmission. We assessed the association between being on ART and sexual risk behavior among those living with HIV in a nationally representative population-based cross-sectional survey of households in South Africa that was conducted in 2012. Of 2237 adults (aged 15-49) who tested HIV-seropositive, 667 (29.8 %) had detectable antiretroviral drugs in their blood specimens. Among males, 77.7 % of those on ART reported having had sex in the past year contrasted with 88.4 % of those not on ART (p = 0.001); among females, 72.2 % of those on ART reported having had sex in the past year while 80.3 % of those not on ART did (p < 0.001). For males and females, the odds of reporting consistent condom use and condom use at last sex were statistically significantly higher for individuals on ART compared to those not on ART (males: consistent condom use aOR 2.8, 95 % CI 1.6-4.9, condom use at last sex aOR 2.6, 95 % CI 1.5-4.6; females: consistent condom use aOR 2.3, 95 % CI 1.7-3.1, condom use at last sex aOR 2.3, 95 % CI 1.7-3.1), while there were no statistically significant differences in odds of reporting multiple sexual partners in the past year. In this nationally representative population-based survey of South African adults, we found evidence of less risky sexual risk behavior among people living with HIV on ART compared to those not on ART.

Does marital status matter in an HIV hyperendemic country? Findings from the 2012 South African National HIV Prevalence, Incidence and Behaviour Survey.

South Africa has experienced declining marriage rates and the increasing practice of cohabitation without marriage. This study aims to improve the understanding of the relationship between marital status and HIV in South Africa, an HIV hyperendemic country, through an analysis of findings from the 2012 South African National HIV Prevalence, Incidence and Behaviour Survey. The nationally representative population-based cross-sectional survey collected data on HIV and socio-demographic and behavioural determinants in South Africa. This analysis considered respondents aged 16 years and older who consented to participate in the survey and provided dried blood spot specimens for HIV testing (N = 17,356). After controlling for age, race, having multiple sexual partners, condom use at last sex, urban/rural dwelling and level of household income, those who were married living with their spouse had significantly reduced odds of being HIV-positive compared to all other marital spouses groups. HIV incidence was 0.27% among respondents who were married living with their spouses; the highest HIV incidence was found in the cohabiting group (2.91%). Later marriage (after age 24) was associated with increased odds of HIV prevalence. Our analysis suggests an association between marital status and HIV prevalence and incidence in contemporary South Africa, where odds of being HIV-positive were found to be lower among married individuals who lived with their spouses compared to all other marital status groups. HIV prevention messages therefore need to be targeted to unmarried populations, especially cohabitating populations. As low socio-economic status, low social cohesion and the resulting destabilization of sexual relationships may explain the increased risk of HIV among unmarried populations, it is necessary to address structural issues including poverty that create an environment unfavourable to stable sexual relationships.

Predictors of knowledge about tuberculosis: results from SANHANES I, a national, cross-sectional household survey in South Africa.

BACKGROUND: South Africa is one of the 22 high tuberculosis burden countries that contribute 80% of the global tuberculosis cases. Tuberculosis is infectious and due to its rapid and easy transmission route poses a threat to population health. Considering the importance of social and psychological factors in influencing health outcomes, appraising knowledge and awareness of tuberculosis, remain vital for effective tuberculosis control. The main aim of this study was to investigate the factors that predict knowledge about tuberculosis among 18-64 year old adults in South Africa. METHODS: A cross-sectional survey method was used. Multi-stage disproportionate, stratified cluster sampling was used to select households within enumeration areas stratified by province and locality type. Based on the Human Sciences Research Council 2007 master sample, 500 Enumerator Areas representative of the socio-demographic profile of South Africa were identified and a random sample of 20 households was randomly selected from each Enumerator Area, yielding an overall sample of 10,000 households. The tuberculosis module contained in the South African National Health And Nutrition Examination Survey I was the only module that examined the social determinants of an infectious disease. This module was questionnaire-based with no biomarkers obtained to screen for the presence of tuberculosis disease among the participants. Data was collected by administering a researcher developed individual level questionnaire. Simple and multiple linear regression was used to determine the independent variables associated with tuberculosis knowledge. RESULTS: Half the sample (52.6%) was female and the majority of the respondents were black African (76.5%). More than two thirds (68.0%) resided in urban areas, 56.9% did not complete high school and half were not in formal employment. Significant predictors of tuberculosis knowledge were race, sex, completion of high school, being in employment, having a diagnosis of the disease in ones' life-time and learning about tuberculosis from television, brochures, health workers, and teachers. CONCLUSIONS: To reduce the burden of tuberculosis in South Africa, media campaigns targeting both rural and urban communities should include conveying accurate information about the disease. Policy makers should also address structural barriers that vulnerable communities face.

New insights into HIV epidemic in South Africa: key findings from the National HIV Prevalence, Incidence and Behaviour Survey, 2012.

This article presents key findings from the 2012 HIV prevalence, incidence and behaviour survey conducted in South Africa and explores trends in the HIV epidemic. A representative household based survey collected behavioural and biomedical data among people of all ages. Chi-squared test for association and formal trend tests (2002, 2005, 2008 and 2012) were used to test for associations and trends in the HIV epidemic across the four surveys. In 2012 a total of 38 431 respondents were interviewed from 11 079 households; 28 997 (67.5%) of 42 950 eligible individuals provided blood specimens. HIV prevalence was 12.2% [95% CI: 11.4-13.1] in 2012 with prevalence higher among females 14.4% than males 9.9%. Adults aged 25-49 years were most affected, 25.2% [95% CI: 23.2-27.3]. HIV prevalence increased from 10.6% [95%CI: 9.8-11.6] in 2008 to 12.2% [95% CI: 11.4-13.1] in 2012 (p < 0.001). Antiretroviral treatment (ART) exposure doubled from 16.6% in 2008 to 31.2% in 2012 (p < 0.001). HIV incidence in 2012 among persons 2 years and older was 1.07% [95% CI: 0.87-1.27], with the highest incidence among Black African females aged 20-34 years at 4.5%. Sexual debut before 15 years was reported by 10.7% of respondents aged 15-24 years, and was significantly higher among male youth than female (16.7% vs. 5.0% respectively, p < 0.001). Reporting of multiple sexual partners in the previous 12 months increased from 11.5% in 2002 to 18.3% in 2012 (p < 0.001). Condom use at last sex dropped from 45.1% in 2008 to 36.2% in 2012 (p < 0.001). Levels of accurate HIV knowledge about transmission and prevention were low and had decreased between 2008 and 2012 from 31.5% to 26.8%. South Africa is on the right track with scaling up ART. However, there have been worrying increases in most HIV-related risk behaviours. These findings suggest that there is a need to scale up prevention methods that integrate biomedical, behavioural, social and structural prevention interventions to reverse the tide in the fight against HIV.

Age at sexual debut: a determinant of multiple partnership among South African youth.

Age at sexual debut is an important determinant of HIV infection. The paper investigates the effects of age at sexual debut on sexual behaviour among South African youth. Among 2 875 respondents who ever had sexual intercourse, 39% had early sexual debut (sexual debut at age 16 years and below). Males (44.6%) were significantly more likely than females (35.1%) to report early sexual debut (odds ratio (OR) = 1.45, p-value < 0.001). Multiple sexual partners are significantly more common among those that had early sexual debut (10.4% vs. 4.8%) than those who had late sexual debut, (OR = 2.29, p-value < 0.001). Those aged 15 to 19 years were 1.4 times more likely to report multiple partners compared to those aged 20 to 24 years. Delaying sexual debut is a strategy many national programmes are promoting. The results of this study provide additional arguments to support such initiatives and show the need to strengthen intervention targeting youth.

HIV drug resistance profile in South Africa: Findings and implications from the 2017 national HIV household survey.

BACKGROUND: HIV drug resistance (HIVDR) testing was included in the 2017 South African national HIV household survey. We describe the prevalence of HIVDR by drug class, age, sex and antiretroviral drugs (ARV) status. METHODS: Dried blood were spots tested for HIV, with Viral load (VL), exposure to ARVs and HIVDR testing among those HIV positive. HIVDR testing was conducted on samples with VL ≥1000 copies/ml using Next Generation Sequencing. Weighted percentages of HIVDR are reported. RESULTS: 697/1,105 (63%) of HIV positive samples were sequenced. HIVDR was detected in samples from 200 respondents (27.4% (95% confidence interval (CI) 22.8-32.6)). Among these 130 (18.9% (95% CI 14.8-23.8)), had resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) only, 63 (7.8% (95% CI 5.6-10.9)) resistance to NNRTIs and nucleoside reverse transcriptase inhibitors, and 3 (0.5% (95% CI 0.1-2.1)) resistance to protease inhibitors. Sixty-five (55.7% (95% CI 42.6-67.9) of ARV-positive samples had HIVDR compared to 112 (22.8% (95% CI 17.7-28.7)), in ARV-negative samples. HIVDR was found in 75.6% (95% CI 59.2-87.3), n = 27, samples from respondents who reported ARV use but tested ARV-negative, and in 15.3% (95% CI 6.3-32.8), n = 7, respondents who reported no ARV use and tested ARV-negative. There were no significant age and sex differences in HIVDR. CONCLUSION: 27% of virally unsuppressed respondents had HIVDR, increasing to 75% among those who had discontinued ARV. Our findings support strengthening first-line ARV regimens by including drugs with a higher resistance barrier and treatment adherence strategies, and close monitoring of HIVDR.

Short Communication: Assessing Estimates of HIV Incidence with a Recent Infection Testing Algorithm That Includes Viral Load Testing and Exposure to Antiretroviral Therapy.

A recent infection testing algorithm (RITA) that includes a test for recent HIV infection and a viral load (VL) test is the recommended strategy to estimate national HIV incidence, reducing false-recent misclassification to <1%. The inclusion of information on exposure to antiretroviral therapy (ART), as a supplement to VL testing, could improve RITA performance by further lowering false-recent misclassification of true long-term infection. In 2012, Kenya and South Africa conducted national population-based surveys that collected information on HIV recency (i.e., HIV antibody seroconversion, on average, in the past 130 days) using the Limiting Antigen avidity (LAg-Avidity) enzyme immunoassay, HIV RNA levels, and ART exposure among HIV-infected respondents aged 15-49 years. In Kenya, ART exposure was defined as testing positive for one or more antiretroviral (ARV) drugs using high-performance liquid chromatography coupled with tandem mass spectrometry, and, if not ARV-positive, self-reporting a history of ART exposure. In South Africa, ART exposure was defined as testing ARV-positive. Two RITA strategies were compared: RITA #1 defined recent infection as testing LAg-Avidity-recent with unsuppressed VL (HIV RNA ≥1,000 copies/ml), and RITA #2 defined recent infection as testing LAg-Avidity-recent with unsuppressed VL and, if unsuppressed, having no ART exposure. RITA-derived incidence among persons aged 15-49 years in Kenya was 0.9% on RITA #1 and 0.8% on RITA #2. In South Africa, RITA-derived incidence was 2.2% on RITA #1 and 1.7% on RITA #2. Among specimens testing recent with unsuppressed VL in Kenya and South Africa, 16.0% and 19.7% had evidence of ART exposure, respectively. Although the performance of a VL- and ART-based RITA was encouraging, additional research is needed across HIV-1 subtypes and subpopulations to calibrate and validate this algorithm.

Equity of antiretroviral treatment use in high HIV burden countries: Analyses of data from nationally-representative surveys in Kenya and South Africa.

OBJECTIVE: To assess changes and equity in antiretroviral therapy (ART) use in Kenya and South Africa. METHODS: We analysed national population-based household surveys conducted in Kenya and South Africa between 2007 and 2012 for factors associated with lack of ART use among people living with HIV (PLHIV) aged 15-64 years. We considered ART use to be inequitable if significant differences in use were found between groups of PLHIV (e.g. by sex). FINDINGS: ART use among PLHIV increased from 29.3% (95% confidence interval [CI]: 22.8-35.8) to 42.5% (95%CI: 37.4-47.7) from 2007 to 2012 in Kenya and 17.4% (95%CI: 14.2-20.9) to 30.3% (95%CI: 27.2-33.6) from 2008 to 2012 in South Africa. In 2012, factors independently associated with lack of ART use among adult Kenyan PLHIV were rural residency (adjusted odds ratio [aOR] 1.98, 95%CI: 1.23-3.18), younger age (15-24 years: aOR 4.25, 95%CI: 1.7-10.63, and 25-34 years: aOR 5.16, 95%CI: 2.73-9.74 versus 50-64 years), nondisclosure of HIV status to most recent sex partner (aOR 2.41, 95%CI: 1.27-4.57) and recent recreational drug use (aOR 2.50, 95%CI: 1.09-5.77). Among South African PLHIV in 2012, lack of ART use was significantly associated with younger age (15-24 years: aOR 4.23, 95%CI: 2.56-6.70, and 25-34 years: aOR 2.84, 95%CI: 1.73-4.67, versus 50-64 years), employment status (aOR 1.61, 95%CI: 1.16-2.23 in students versus unemployed), and recent recreational drug use (aOR 4.56, 95%CI: 1.79-11.57). CONCLUSION: Although we found substantial increases in ART use in both countries over time, we identified areas needing improvement including among rural Kenyans, students in South Africa, and among young people and drug users in both countries.

National South African HIV prevalence estimates robust despite substantial test non-participation.

BACKGROUND: South African (SA) national HIV seroprevalence estimates are of crucial policy relevance in the country, and for the worldwide HIV response. However, the most recent nationally representative HIV test survey in 2012 had 22% test non-participation, leaving the potential for substantial bias in current seroprevalence estimates, even after controlling for selection on observed factors. OBJECTIVE: To re-estimate national HIV prevalence in SA, controlling for bias due to selection on both observed and unobserved factors in the 2012 SA National HIV Prevalence, Incidence and Behaviour Survey. METHODS: We jointly estimated regression models for consent to test and HIV status in a Heckman-type bivariate probit framework. As selection variable, we used assigned interviewer identity, a variable known to predict consent but highly unlikely to be associated with interviewees' HIV status. From these models, we estimated the HIV status of interviewed participants who did not test. RESULTS: Of 26 710 interviewed participants who were invited to test for HIV, 21.3% of females and 24.3% of males declined. Interviewer identity was strongly correlated with consent to test for HIV; declining a test was weakly associated with HIV serostatus. Our HIV prevalence estimates were not significantly different from those using standard methods to control for bias due to selection on observed factors: 15.1% (95% confidence interval (CI) 12.1 - 18.6) v. 14.5% (95% CI 12.8 - 16.3) for 15 - 49-year-old males; 23.3% (95% CI 21.7 - 25.8) v. 23.2% (95% CI 21.3 - 25.1) for 15 - 49-year-old females. CONCLUSION: The most recent SA HIV prevalence estimates are robust under the strongest available test for selection bias due to missing data. Our findings support the reliability of inferences drawn from such data.

Age-disparate sex and HIV risk for young women from 2002 to 2012 in South Africa.

INTRODUCTION: Age-disparate sex has long been considered a factor that increases HIV risk for young women in South Africa. However, recent studies from specific regions in South Africa have found conflicting evidence. Few studies have assessed the association between age-disparate partnerships (those involving an age gap of 5 years or more) and HIV risk at the national level. This study investigates the relationship between age-disparate sex and HIV status among young women aged 15-24 in South Africa. METHODS: Nationally representative weighted data from the 2002, 2005, 2008, and 2012 South African National HIV Surveys were analysed for young women aged 15-24 years using bivariate analyses and multiple logistic regressions. RESULTS: After conducting multiple logistic regression analyses and controlling for confounders, young women with age-disparate partners had greater odds of being HIV positive in every survey year: 2002 (aOR = 1.74, 95%CI: 0.81-3.76, p = 0.16); 2005 (aOR = 2.11, 95%CI: 1.22-3.66, p < 0.01); 2008 (aOR = 2.02, 95%CI: 1.24-3.29, p < 0.01); 2012 (aOR = 1.53, 95%CI: 0.92-2.54, p < 0.1). The odds of being HIV positive increased for each year increase in their male partner's age in 2002 (aOR = 1.10, 95%CI: 0.98-1.22, p = 0.11), 2005 (aOR = 1.10, 95%CI: 1.03-1.17, p < 0.01), 2008 (aOR = 1.08, 95%CI: 1.01-1.15, p < 0.05), and 2012 (aOR = 1.08, 95%CI: 1.01-1.16, p < 0.05). Findings were statistically significant (p < 0.1) for the years 2005, 2008, and 2012. CONCLUSION: Our findings suggest that age-disparate sex continues to be a risk factor for young women aged 15-24 in South Africa at a national level. These results may reflect variation in HIV risk at the national level compared to the differing results from recent studies in a demographic surveillance system and trial contexts. In light of recent contradictory study results, further research is required on the relationship between age-disparate sex and HIV for a more nuanced understanding of young women's HIV risk.

Rates of HIV testing and diagnosis in South Africa: successes and challenges.

BACKGROUND: UNAIDS aims for 90% of HIV-positive individuals to be diagnosed by 2020, but few attempts have been made in developing countries to estimate the fraction of the HIV-positive population that has been diagnosed. METHODS: To estimate the rate of HIV diagnosis in South Africa, reported numbers of HIV tests performed in the South African public and private health sectors were aggregated, and estimates of HIV prevalence in individuals tested for HIV were combined. The data were integrated into a mathematical model of the South African HIV epidemic, which was additionally calibrated to estimates of the fraction of the population ever tested for HIV, as reported in three national household surveys. RESULTS: The fraction of HIV-positive adults who were undiagnosed declined from more than 80% in the early 2000s to 23.7% [95% confidence interval (95% CI) 23.1-24.3] in 2012. The undiagnosed proportion in 2012 was substantially higher in men (31.9%, 95% CI 29.7-34.3) than in women (19.0%, 95% CI 17.9-19.9). Projected probabilities of experiencing disease progression (CD4 cell count <350 cells/µl) without diagnosis are more than 50% for most HIV-positive adults over the age of 40. The fraction of HIV-positive adults who are undiagnosed is projected to decline to 8.9% by 2020 if current targets (10 million tests per annum) are met. CONCLUSION: South Africa has made significant progress in expanding access to HIV testing, and at current testing rates, the target of 90% of HIV-positive adults diagnosed by 2020 is likely to be reached. However, uptake is relatively low in men and older adults.

A Comparison of South African National HIV Incidence Estimates: A Critical Appraisal of Different Methods.

BACKGROUND: The interpretation of HIV prevalence trends is increasingly difficult as antiretroviral treatment programs expand. Reliable HIV incidence estimates are critical to monitoring transmission trends and guiding an effective national response to the epidemic. METHODS AND FINDINGS: We used a range of methods to estimate HIV incidence in South Africa: (i) an incidence testing algorithm applying the Limiting-Antigen Avidity Assay (LAg-Avidity EIA) in combination with antiretroviral drug and HIV viral load testing; (ii) a modelling technique based on the synthetic cohort principle; and (iii) two dynamic mathematical models, the EPP/Spectrum model package and the Thembisa model. Overall, the different incidence estimation methods were in broad agreement on HIV incidence estimates among persons aged 15-49 years in 2012. The assay-based method produced slightly higher estimates of incidence, 1.72% (95% CI 1.38 - 2.06), compared with the mathematical models, 1.47% (95% CI 1.23 - 1.72) in Thembisa and 1.52% (95% CI 1.43 - 1.62) in EPP/Spectrum, and slightly lower estimates of incidence compared to the synthetic cohort, 1.9% (95% CI 0.8 - 3.1) over the period from 2008 to 2012. Among youth aged 15-24 years, a declining trend in HIV incidence was estimated by all three mathematical estimation methods. CONCLUSIONS: The multi-method comparison showed similar levels and trends in HIV incidence and validated the estimates provided by the assay-based incidence testing algorithm. Our results confirm that South Africa is the country with the largest number of new HIV infections in the world, with about 1 000 new infections occurring each day among adults aged 15-49 years in 2012.

Assessment of epidemic projections using recent HIV survey data in South Africa: a validation analysis of ten mathematical models of HIV epidemiology in the antiretroviral therapy era.

BACKGROUND: Mathematical models are widely used to simulate the effects of interventions to control HIV and to project future epidemiological trends and resource needs. We aimed to validate past model projections against data from a large household survey done in South Africa in 2012. METHODS: We compared ten model projections of HIV prevalence, HIV incidence, and antiretroviral therapy (ART) coverage for South Africa with estimates from national household survey data from 2012. Model projections for 2012 were made before the publication of the 2012 household survey. We compared adult (age 15-49 years) HIV prevalence in 2012, the change in prevalence between 2008 and 2012, and prevalence, incidence, and ART coverage by sex and by age groups between model projections and the 2012 household survey. FINDINGS: All models projected lower prevalence estimates for 2012 than the survey estimate (18·8%), with eight models' central projections being below the survey 95% CI (17·5-20·3). Eight models projected that HIV prevalence would remain unchanged (n=5) or decline (n=3) between 2008 and 2012, whereas prevalence estimates from the household surveys increased from 16·9% in 2008 to 18·8% in 2012 (difference 1·9, 95% CI -0·1 to 3·9). Model projections accurately predicted the 1·6 percentage point prevalence decline (95% CI -0·3 to 3·5) in young adults aged 15-24 years, and the 2·2 percentage point (0·5 to 3·9) increase in those aged 50 years and older. Models accurately represented the number of adults on ART in 2012; six of ten models were within the survey 95% CI of 1·54-2·12 million. However, the differential ART coverage between women and men was not fully captured; all model projections of the sex ratio of women to men on ART were lower than the survey estimate of 2·22 (95% CI 1·73-2·71). INTERPRETATION: Projections for overall declines in HIV epidemics during the ART era might have been optimistic. Future treatment and HIV prevention needs might be greater than previously forecasted. Additional data about service provision for HIV care could help inform more accurate projections. FUNDING: Bill & Melinda Gates Foundation.

Recent HIV prevalence trends among pregnant women and all women in sub-Saharan Africa: implications for HIV estimates.

OBJECTIVES: National population-wide HIV prevalence and incidence trends in sub-Saharan Africa (SSA) are indirectly estimated using HIV prevalence measured among pregnant women attending antenatal clinics (ANC), among other data. We evaluated whether recent HIV prevalence trends among pregnant women are representative of general population trends. DESIGN: Serial population-based household surveys in 13 SSA countries. METHODS: We calculated HIV prevalence trends among all women aged 15-49 years and currently pregnant women between surveys conducted from 2003 to 2008 (period 1) and 2009 to 2012 (period 2). Log-binomial regression was used to test for a difference in prevalence trend between the two groups. Prevalence among pregnant women was age-standardized to represent the age distribution of all women. RESULTS: Pooling data for all countries, HIV prevalence declined among pregnant women from 6.5 [95% confidence interval (CI) 5.3-7.9%] to 5.3% (95% CI 4.2-6.6%) between periods 1 and 2, whereas it remained unchanged among all women at 8.4% (95% CI 8.0-8.9%) in period 1 and 8.3% (95% CI 7.9-8.8%) in period 2. Prevalence declined by 18% (95% CI -9-38%) more in pregnant women than nonpregnant women. Estimates were similar in Western, Eastern, and Southern regions of SSA; none were statistically significant (P>0.05). HIV prevalence decreased significantly among women aged 15-24 years while increasing significantly among women 35-49 years, who represented 29% of women but only 15% of pregnant women. Age-standardization of prevalence in pregnant women did not reconcile the discrepant trends because at older ages prevalence was lower among pregnant women than nonpregnant women. CONCLUSION: As HIV prevalence in SSA has shifted toward older, less-fertile women, HIV prevalence among pregnant women has declined more rapidly than prevalence in women overall. Interpretation of ANC prevalence data to inform national HIV estimates should account for both age-specific fertility patterns and HIV-related sub-fertility.

Perceptions about the acceptability and prevalence of HIV testing and factors influencing them in different communities in South Africa.

HIV counselling and testing (HCT) is considered important because it is an entry point to a comprehensive continuum of care for HIV/AIDS. The South African Department of Health launched an HCT campaign in April 2010, and this reached 13,269,746 people by June 2011, of which 16% tested HIV positive and 400,000 of those were initiated into antiretroviral treatment. The overall objective of this project was to gain insight into the general perceptions about HIV testing in the different South African communities. Factors influencing testing in these communities were also explored. Discussions with twelve focus groups (FG) of 8-12 participants each were conducted with male and female participants recruited from both urban formal and informal communities in Cape Town and Durban. Participants included four racial groups represented by different age groups as follows: adolescents (12-17 years), youth (18-24 years) and adults (25 years and older). Data were analyzed using thematic coding. Among the key themes that emerged from the findings were the inaccurate perception of risk, fear of testing HIV positive, stigma and discrimination. Participants from both African and Indian FGs reported being less likely to do self-initiated HIV testing and counselling, while those from the FG consisting of young whites were more likely to learn about their HIV status through blood donations and campus HIV testing campaigns. Most FGs said they were likely to test if they understood the testing process better and also if the results are kept confidential. The present findings reiterate the importance of spreading positive messages and ensuring confidentiality for HIV testing in a society where there is still some stigma associated with people living with HIV/AIDS. This can partly be accomplished by the continuation of the national HCT campaign, which has been a considerable success in the fight against HIV/AIDS in South Africa during the past two years.

The effect of changes in condom usage and antiretroviral treatment coverage on human immunodeficiency virus incidence in South Africa: a model-based analysis.

This study aims to assess trends in human immunodeficiency virus (HIV) incidence in South Africa, and to assess the extent to which prevention and treatment programmes have reduced HIV incidence. Two models of the South African HIV epidemic, the STI (sexually transmitted infection)-HIV Interaction model and the ASSA2003 AIDS and Demographic model, were adapted. Both models were fitted to age-specific HIV prevalence data from antenatal clinic surveys and household surveys, using a Bayesian approach. Both models suggest that HIV incidence in 15-49 year olds declined significantly between the start of 2000 and the start of 2008: by 27 per cent (95% CI: 21-32%) in the STI-HIV model and by 31 per cent (95% CI: 23-39%) in the ASSA2003 model, when expressed as a percentage of incidence rates in 2000. By 2008, the percentage reduction in incidence owing to increased condom use was 37 per cent (95% CI: 34-41%) in the STI-HIV model and 23 per cent (95% CI: 14-34%) in the ASSA2003 model. Both models also estimated a small reduction in incidence owing to antiretroviral treatment by 2008. Increased condom use therefore appears to be the most significant factor explaining the recent South African HIV incidence decline.

The effect of early initiation of antiretroviral treatment in infants on pediatric AIDS mortality in South Africa: a model-based analysis.

BACKGROUND: Guidelines for treatment of pediatric HIV have recently changed to recommend that all infants who are identified as HIV-infected should start antiretroviral treatment (ART) immediately, regardless of their immunologic or clinical status. This study aims to assess the likely impact of this change in guideline in South Africa. METHODS: A mathematical model was developed to simulate mother-to-child transmission of HIV, disease progression, and death of HIV-infected children <15 years of age. The model is calibrated to South African data sources, including prevention of mother-to-child transmission program coverage data, pre-ART survival data, ART program statistics, and pediatric HIV prevalence studies. RESULTS: Relative to what would be expected in the absence of early ART initiation, the number of infant AIDS deaths over the 2010-2025 period is expected to drop by 23.6% (95% confidence interval [CI]: 22.5-24.5%) at current levels of polymerase chain reaction (PCR) diagnosis, and by 34.2% (95% CI: 32.7-35.6%) if PCR diagnosis increases to 80% of perinatally infected infants at 2 months. However, the pediatric HIV disease burden has shifted toward older children in recent years. The effect of early ART on total pediatric AIDS mortality during the 2010-2025 period is therefore modest: a 9.8% reduction (95% CI: 7.9-12.6%) at current levels of PCR diagnosis, and a 14.2% reduction (95% CI: 11.4-18.2%) if PCR coverage increases to 80% of perinatally infected infants. CONCLUSION: The changes in ART guidelines for infants will have a significant impact on pediatric AIDS mortality at young ages, but further efforts are required to reduce the substantial growing AIDS mortality in older children.

The contribution of maternal HIV seroconversion during late pregnancy and breastfeeding to mother-to-child transmission of HIV.

BACKGROUND: The prevention of mother-to-child transmission (PMTCT) of HIV has been focused mainly on women who are HIV positive at their first antenatal visit, but there is uncertainty regarding the contribution to overall transmission from mothers who seroconvert after their first antenatal visit and before weaning. METHOD: A mathematical model was developed to simulate changes in mother-to-child transmission of HIV over time, in South Africa. The model allows for changes in infant feeding practices as infants age, temporal changes in the provision of antiretroviral prophylaxis and counseling on infant feeding, as well as temporal changes in maternal HIV prevalence and incidence. RESULTS: The proportion of mother-to-child transmission (MTCT) from mothers who seroconverted after their first antenatal visit was 26% [95% confidence interval (CI): 22% to 30%] in 2008, or 15,000 of 57,000 infections. It is estimated that by 2014, total MTCT will reduce to 39,000 per annum, and transmission from mothers seroconverting after their first antenatal visit will reduce to 13,000 per annum, accounting for 34% (95% CI: 29% to 39%) of MTCT. If maternal HIV incidence during late pregnancy and breastfeeding were reduced by 50% after 2010, and HIV screening were repeated in late pregnancy and at 6-week immunization visits after 2010, the average annual number of MTCT cases over the 2010-2015 period would reduce by 28% (95% CI: 25% to 31%), from 39,000 to 28,000 per annum. CONCLUSION: Maternal seroconversion during late pregnancy and breastfeeding contributes significantly to the pediatric HIV burden and needs greater attention in the planning of prevention of MTCT programs.