Dataset Information

A decline in new HIV infections in South Africa: estimating HIV incidence from three national HIV surveys in 2002, 2005 and 2008.

ABSTRACT:

Background

Three national HIV household surveys were conducted in South Africa, in 2002, 2005 and 2008. A novelty of the 2008 survey was the addition of serological testing to ascertain antiretroviral treatment (ART) use.

Methods and principal findings

We used a validated mathematical method to estimate the rate of new HIV infections (HIV incidence) in South Africa using nationally representative HIV prevalence data collected in 2002, 2005 and 2008. The observed HIV prevalence levels in 2008 were adjusted for the effect of antiretroviral treatment on survival. The estimated "excess" HIV prevalence due to ART in 2008 was highest among women 25 years and older and among men 30 years and older. In the period 2002-2005, the HIV incidence rate among men and women aged 15-49 years was estimated to be 2.0 new infections each year per 100 susceptible individuals (/100pyar) (uncertainty range: 1.2-3.0/100pyar). The highest incidence rate was among 15-24 year-old women, at 5.5/100pyar (4.5-6.5). In the period 2005-2008, incidence among men and women aged 15-49 was estimated to be 1.3/100 (0.6-2.5/100pyar), although the change from 2002-2005 was not statistically significant. However, the incidence rate among young women aged 15-24 declined by 60% in the same period, to 2.2/100pyar, and this change was statistically significant. There is evidence from the surveys of significant increases in condom use and awareness of HIV status, especially among youth.

Conclusions

Our analysis demonstrates how serial measures of HIV prevalence obtained in population-based surveys can be used to estimate national HIV incidence rates. We also show the need to determine the impact of ART on observed HIV prevalence levels. The estimation of HIV incidence and ART exposure is crucial to disentangle the concurrent impact of prevention and treatment programs on HIV prevalence.

SUBMITTER: Rehle TM

PROVIDER: S-EPMC2885415 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A decline in new HIV infections in South Africa: estimating HIV incidence from three national HIV surveys in 2002, 2005 and 2008.

Rehle Thomas M TM Hallett Timothy B TB Shisana Olive O Pillay-van Wyk Victoria V Zuma Khangelani K Carrara Henri H Jooste Sean S

PloS one 20100614 6

<h4>Background</h4>Three national HIV household surveys were conducted in South Africa, in 2002, 2005 and 2008. A novelty of the 2008 survey was the addition of serological testing to ascertain antiretroviral treatment (ART) use.<h4>Methods and principal findings</h4>We used a validated mathematical method to estimate the rate of new HIV infections (HIV incidence) in South Africa using nationally representative HIV prevalence data collected in 2002, 2005 and 2008. The observed HIV prevalence lev ...[more]

PMID: 20559425

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Project description:BACKGROUND:HIV testing contributes to the prevention and control of the HIV epidemic in the general population. South Africa has made strides to improve HIV testing towards reaching the first of the UNAIDS 90-90-90 targets by 2020. However, to date no nationally representative analysis has examined temporal trends and factors associated with HIV testing among youth and adults in the country. AIM:This study aimed to examine the trends and associations with ever having tested for HIV among youth and adults aged 15 years and older in South Africa using the 2005, 2008, 2012 and 2017 nationally representative population-based household surveys. METHODS:The analysis of the data collected used multi-stage stratified cluster randomised cross-sectional design. P-trend chi-squared test was used to identify any significant changes over the four study periods. Bivariate and multivariate logistic regression analysis was conducted to determine factors associated with HIV testing in each of the survey periods. RESULTS:Ever having tested for HIV increased substantially from 2005 (30.6%, n = 16 112), 2008 (50.4%, n = 13 084), 2012 (65.5%, n = 26 381), to 2017 (75.2%, n = 23 190). Those aged 50 years and older were significantly less likely to ever have tested for HIV than those aged 25-49 years. Those residing in rural areas were significantly less likely to have tested for HIV as compared to people from urban areas. There was a change in HIV testing among race groups with Whites, Coloureds and Indian/Asians testing more in 2005 and 2008 and Black Africans in 2017. Marriage, education and employment were significantly associated with increased likelihood of ever testing for HIV. Those who provided a blood specimen for laboratory HIV testing in the survey rounds and were found to have tested positive were more likely to have ever tested for HIV previously. CONCLUSION:The results show that overall there has been an increase in ever having an HIV test in the South African population over time. The findings also suggest that for South Africa to close the testing gap and reach the first of the UNAIDS 90-90-90 targets by 2020, targeted programmes aimed at increasing access and utilization of HIV testing in young people, males, those not married, the less educated, unemployed and those residing in rural areas of South Africa should be prioritised.

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Project description:IntroductionAge-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.MethodsNationally 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.ResultsAfter 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.ConclusionOur 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.

Project description:CONTEXT:Over the past decade, chronic illnesses with ophthalmic sequelae such as diabetes and diabetic retinopathy have increased. OBJECTIVES:To estimate prevalence of nonrefractive visual impairment and to describe its relationship with demographic and systemic risk factors including diagnosed diabetes. DESIGN, SETTING, AND PARTICIPANTS:The National Health and Nutrition Examination Survey (NHANES) examined a representative sample of the US noninstitutionalized population. In 1999-2002 and 2005-2008, 9471 and 10,480 participants aged 20 years or older received questionnaires, laboratory tests, and physical examinations. Visual acuity of less than 20/40 aided by autorefractor was classified as nonrefractive visual impairment. MAIN OUTCOME MEASURE:Nonrefractive visual impairment. RESULTS:Weighted prevalence of nonrefractive visual impairment increased 21% among US adults aged 20 years and older from 1.4% in 1999-2002 to 1.7% in 2005-2008 (P = .03); and increased 40% among non-Hispanic whites aged 20-39 years from 0.5% to 0.7% (P = .008). In multivariable analyses, statistically significant risk factors for nonrefractive visual impairment in 1999-2002 included age (per year odds ratio [OR], 1.07; 95% CI, 1.05-1.09), poverty (OR, 2.18; 95% CI, 1.31-3.64), lack of insurance (OR, 1.85; 95% CI, 1.16-2.95), and diabetes with 10 or more years since diagnosis (OR, 1.93; 95% CI, 1.15-3.25). In 2005-2008, risk factors included age (OR, 1.05; 95% CI, 1.04-1.07), poverty (OR, 2.23; 95% CI, 1.55-3.22), education less than high school (OR, 2.11; 95% CI, 1.54-2.90), and diabetes with 10 or more years since diagnosis (OR, 2.67; 95% CI, 1.64-4.37). Prevalence of diabetes with 10 or more years since diagnosis increased 22% overall from 2.8% to 3.6% (P = .02); and 133% among non-Hispanic whites aged 20-39 years from 0.3% to 0.7% (P < .001). CONCLUSION:Prevalence of nonrefractive visual impairment was significantly higher in 2005-2008 than in 1999-2002 and may be attributable, in part, to higher prevalence of diabetes, an associated risk factor that increased in prevalence during this time period.

Dataset Information

A decline in new HIV infections in South Africa: estimating HIV incidence from three national HIV surveys in 2002, 2005 and 2008.

Background

Methods and principal findings

Conclusions

Publications

A decline in new HIV infections in South Africa: estimating HIV incidence from three national HIV surveys in 2002, 2005 and 2008.

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