Coital frequency and condom use in monogamous and concurrent sexual relationships in Cape Town,South Africa

Introduction

A decreased frequency of unprotected sex during episodes of concurrent relationships may dramatically reduce the role of concurrency in accelerating the spread of HIV. Such a decrease could be the result of coital dilution – the reduction in per-partner coital frequency from additional partners – and/or increased condom use during concurrency. To study the effect of concurrency on the frequency of unprotected sex, we examined sexual behaviour data from three communities with high HIV prevalence around Cape Town, South Africa.

Methods

We conducted a cross-sectional survey from June 2011 to February 2012 using audio computer-assisted self-interviewing to reconstruct one-year sexual histories, with a focus on coital frequency and condom use. Participants were randomly sampled from a previous TB and HIV prevalence survey. Mixed effects logistic and Poisson regression models were fitted to data from 527 sexually active adults reporting on 1210 relationship episodes to evaluate the effect of concurrency status on consistent condom use and coital frequency.

Results

The median of the per-partner weekly average coital frequency was 2 (IQR: 1–3), and consistent condom use was reported for 36% of the relationship episodes. Neither per-partner coital frequency nor consistent condom use changed significantly during episodes of concurrency (aIRR=1.05; 95% confidence interval (CI): 0.99–1.24 and aOR=1.01; 95% CI: 0.38–2.68, respectively). Being male, coloured, having a tertiary education, and having a relationship between 2 weeks and 9 months were associated with higher coital frequencies. Being coloured, and having a relationship lasting for more than 9 months, was associated with inconsistent condom use.

Conclusions

We found no evidence for coital dilution or for increased condom use during concurrent relationship episodes in three communities around Cape Town with high HIV prevalence. Given the low levels of self-reported consistent condom use, our findings suggest that if the frequency of unprotected sex with each of the sexual partners is sustained during concurrent relationships, HIV-positive individuals with concurrent partners may disproportionately contribute to onward HIV transmission.     

Early adolescent pregnancy increases risk of incident HIV infection in the Eastern Cape,South Africa: a longitudinal study

Introduction

Adolescents having unprotected heterosexual intercourse are at risk of HIV infection and unwanted pregnancy. However, there is little evidence to indicate whether pregnancy in early adolescence increases the risk of subsequent HIV infection. In this paper, we tested the hypothesis that adolescent pregnancy (aged 15 or younger) increases the risk of incident HIV infection in young South African women.

Methods

We assessed 1099 HIV-negative women, aged 15–26 years, who were volunteer participants in a cluster-randomized, controlled HIV prevention trial in the predominantly rural Eastern Cape province of South Africa. All of these young women had at least one additional HIV test over two years of follow-up. Outcomes were HIV incidence rates per 100 person years and HIV incidence rate ratios (IRRs) estimated by Poisson multivariate models. Three pregnancy categories were created for the Poisson model: early adolescent pregnancy (a first pregnancy at age 15 years or younger); later adolescent pregnancy (a first pregnancy at age 16 to 19 years); and women who did not report an adolescent pregnancy. Models were adjusted for study design, age, education, time since first sexual experience, socio-economic status, childhood trauma and herpes simplex virus type 2 infection.

Results

HIV incidence rates were 6.0 per 100 person years over two years of follow-up. The adjusted IRR was 3.02 (95% CI 1.50–6.09) for a pregnancy occurring at age 15 or younger. Women with pregnancies occurring between 16 and 19 years of age did not have a higher incidence of HIV (IRR 1.08; 95% CI 0.64–1.84). Early adolescent pregnancies were associated with higher partner numbers and a greater age difference with partners.

Conclusions

Early adolescent pregnancies increase the incidence of HIV among South African women. The higher risk is associated with sexual risk behaviours such as higher partner numbers and a greater age difference with partners rather than a biological explanation of hormonal changes during pregnancy.     

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. Conclusions : 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.     

Casual sex and concurrent sexual partnerships among young people from an Yi community with a high prevalence of HIV in China

Liangshan Prefecture in Sichuan province, China, has a high prevalence of HIV infection, which is reflective of a change in the mode of transmission from injection drug use (IDU) to heterosexual intercourse. However, few studies focus on HIV-related heterosexual risk behaviours among the majority Yi population. The objectives of this study were to explore the characteristics of an egocentric sexual network and estimate the prevalence of casual sexual behaviour. Yi villagers (n=108), aged 15–35 years, who reported having had sex within the previous year were interviewed as to their sexual behaviours and networks. In-depth interviews and focus group discussions provided supplementary information on sexual norms. Logistic regression analysis was used to calculate unadjusted odds ratios (ORs) and 95% confidence intervals (CIs). Most of the respondents reported having had casual sex at some time in their life, and 66.7% reported multiple sexual partnerships. Only 21.3% reported ever having used a condom. During the study year, a total of 137 partners were involved in 153 sexual partnerships. Among the reported sexual partnerships, 67.3% originated from a casual sexual relationship. For network members in components of size ≥3, 56.9% were involved in concurrent sexual partnerships. Having never been married (OR: 2.11; 95% CI: 1.03–4.33) and younger age (OR: 0.89; 95% CI: 0.83–0.95) were both associated with being in a component of size ≥3. Size (OR: 2.99; 95% CI: 1.17–7.66), pair (OR: 0.54; 95% CI: 0.39–0.74), the number of weak components of the egocentric sexual network (OR: 30.04; 95% CI: 6.47–139.46) and gender (OR: 0.19; 95% CI: 0.06–0.67) were all associated with being in concurrent sexual partnerships. HIV-related interventions for the Yi ethnic minority in Sichuan province must therefore address concurrent sexual partnerships and promote condom use.     

Impact and cost-effectiveness of the national scale-up of HIV pre-exposure prophylaxis among female sex workers in South Africa: a modelling analysis

Introduction

In 2016, South Africa (SA) initiated a national programme to scale-up pre-exposure prophylaxis (PrEP) among female sex workers (FSWs), with ∼20,000 PrEP initiations among FSWs (∼14% of FSW) by 2020. We evaluated the impact and cost-effectiveness of this programme, including future scale-up scenarios and the potential detrimental impact of the COVID-19 pandemic.

Methods

A compartmental HIV transmission model for SA was adapted to include PrEP. Using estimates on self-reported PrEP adherence from a national study of FSW (67.7%) and the Treatment and Prevention for FSWs (TAPS) PrEP demonstration study in SA (80.8%), we down-adjusted TAPS estimates for the proportion of FSWs with detectable drug levels (adjusted range: 38.0–70.4%). The model stratified FSW by low (undetectable drug; 0% efficacy) and high adherence (detectable drug; 79.9%; 95% CI: 67.2–87.6% efficacy). FSWs can transition between adherence levels, with lower loss-to-follow-up among highly adherent FSWs (aHR: 0.58; 95% CI: 0.40–0.85; TAPS data). The model was calibrated to monthly data on the national scale-up of PrEP among FSWs over 2016–2020, including reductions in PrEP initiations during 2020. The model projected the impact of the current programme (2016–2020) and the future impact (2021–2040) at current coverage or if initiation and/or retention are doubled. Using published cost data, we assessed the cost-effectiveness (healthcare provider perspective; 3% discount rate; time horizon 2016–2040) of the current PrEP provision.

Results

Calibrated to national data, model projections suggest that 2.1% of HIV-negative FSWs were currently on PrEP in 2020, with PrEP preventing 0.45% (95% credibility interval, 0.35–0.57%) of HIV infections among FSWs over 2016–2020 or 605 (444–840) infections overall. Reductions in PrEP initiations in 2020 possibly reduced infections averted by 18.57% (13.99–23.29). PrEP is cost-saving, with $1.42 (1.03–1.99) of ART costs saved per dollar spent on PrEP. Going forward, existing coverage of PrEP will avert 5,635 (3,572–9,036) infections by 2040. However, if PrEP initiation and retention doubles, then PrEP coverage increases to 9.9% (8.7–11.6%) and impact increases 4.3 times with 24,114 (15,308–38,107) infections averted by 2040.

Conclusions

Our findings advocate for the expansion of PrEP to FSWs throughout SA to maximize its impact. This should include strategies to optimize retention and should target women in contact with FSW services.     

Acute dialysis in HIV-positive patients in Cape Town, South Africa

Aim: The prognosis for HIV patients needing acute dialysis is uncertain. The aim of this study was to describe the clinical presentation, renal diagnoses and outcomes of HIV patients who underwent acute haemodialysis at Groote Schuur Hospital in the period 2002–2007. Methods: A retrospective review of case records of HIV patients who underwent acute haemodialysis was conducted. Results: One hundred and seventeen patients were reviewed (median age 34.0 years (29.0–40.0) 53.8% men, 93.2% black Africans) and 33 had a renal biopsy. Acute tubular necrosis (ATN) was diagnosed in 68 patients. Recovery of renal function occurred in 33.3% of all patients while in 25.7% treatment was withdrawn and 41.0% died in hospital. Suspected ATN was the commonest cause of renal disease in those who recovered renal function (82.1%). A higher CD4 count (odds ratio (OR) = 0.994, P = 0.007), lower pre‐dialysis serum creatinine (<1230 µmol/L) and longer hospitalization (OR = 0.93, P = 0.006) significantly correlated with survival. Conclusion: There is a good chance of survival for HIV patients needing acute dialysis when the diagnosis is ATN, and when the CD4 count is more than 200 cells/mm³.     

COVID-19 among adults living with HIV: correlates of mortality among public sector healthcare users in Western Cape,South Africa

Introduction

While a large proportion of people with HIV (PWH) have experienced SARS-CoV-2 infections, there is uncertainty about the role of HIV disease severity on COVID-19 outcomes, especially in lower-income settings. We studied the association of mortality with characteristics of HIV severity and management, and vaccination, among adult PWH.

Methods

We analysed observational cohort data on all PWH aged ≥15 years experiencing a diagnosed SARS-CoV-2 infection (until March 2022), who accessed public sector healthcare in the Western Cape province of South Africa. Logistic regression was used to study the association of mortality with evidence of antiretroviral therapy (ART) collection, time since first HIV evidence, CD4 cell count, viral load (among those with evidence of ART collection) and COVID-19 vaccination, adjusting for demographic characteristics, comorbidities, admission pressure, location and time period.

Results

Mortality occurred in 5.7% (95% CI: 5.3,6.0) of 17,831 first-diagnosed infections. Higher mortality was associated with lower recent CD4, no evidence of ART collection, high or unknown recent viral load and recent first HIV evidence, differentially by age. Vaccination was protective. The burden of comorbidities was high, and tuberculosis (especially more recent episodes of tuberculosis), chronic kidney disease, diabetes and hypertension were associated with higher mortality, more strongly in younger adults.

Conclusions

Mortality was strongly associated with suboptimal HIV control, and the prevalence of these risk factors increased in later COVID-19 waves. It remains a public health priority to ensure PWH are on suppressive ART and vaccinated, and manage any disruptions in care that occurred during the pandemic. The diagnosis and management of comorbidities, including for tuberculosis, should be optimized.     

The aetiology of adult burns in the Western Cape, South Africa

Rural to urban migration to major cities in South Africa continues to lead to the proliferation of informal settlements. There is little recent published data on the epidemiology of adult burns in the Western Cape, South Africa. A retrospective review of patients on the Burn Unit database was undertaken, looking at patients admitted to the Burn Unit between January 2003 and December 2008. This study discusses the characteristics and outcome of patients who were treated at the Tygerburg Burn unit. A total of 1908 patients were admitted to the burn unit during the 6 year period under review. Most fatal injuries occurred in the 20-40 year age group. Injuries due to shack fires and fuel stoves comprised 21% (399) of all admissions. Mortality due to these injuries comprised 28% (137) of total mortality. Gas stoves accounted for 24% with kerosene stoves accounting for 71% of injuries. The burn death rate in this study (25%) was found to have increased dramatically from the last audit done from 1986 to 1995 in which a burn death rate of 7.5% was observed. Reasons for this are explored. It is likely that those with HIV/AIDS have poorer outcomes. Shack fires and injuries due to fuel stoves are a common reason for admission to the burn unit and mostly involve young male individuals. Other research from the Southern African region does not mention shack fires as a separate entity making it difficult to obtain an accurate idea of the scale of the problem. Their injuries are severe with a high mortality. The use of kerosene stoves are a major contributing factor. Recommendations include enforceable legislation to promote safer stove design, research into safer bio fuels and materials for building shacks as well promoting fire safety among schoolchildren in the community. Further research is needed to determine the impact of HIV/AIDS on the outcome of acute burns within the Southern African region.     

Temporal trends in TB notification rates during ART scale-up in Cape Town: an ecological analysis

Introduction

Although antiretroviral therapy (ART) reduces individual tuberculosis (TB) risk by two-thirds, the population-level impact remains uncertain. Cape Town reports high TB notification rates associated with endemic HIV. We examined population trends in TB notification rates during a 10-year period of expanding ART.

Methods

Annual Cape Town TB notifications were used as numerators and mid-year Cape Town populations as denominators. HIV-stratified population was calculated using overall HIV prevalence estimates from the Actuarial Society of South Africa AIDS and Demographic model. ART provision numbers from Western Cape government reports were used to calculate overall ART coverage. We calculated rates per 100,000 population over time, overall and stratified by HIV status. Rates per 100,000 total population were also calculated by ART use at treatment initiation. Absolute numbers of notifications were compared by age and sub-district. Changes over time were described related to ART provision in the city as a whole (ART coverage) and by sub-district (numbers on ART).

Results

From 2003 to 2013, Cape Town''s population grew from 3.1 to 3.7 million inhabitants, and estimated HIV prevalence increased from 3.6 to 5.2%. ART coverage increased from 0 to 63% in 2013. TB notification rates declined by 16% (95% confidence interval (CI), 14–17%) from a 2008 peak (851/100,000) to a 2013 nadir (713/100,000). Decreases were higher among the HIV-positive (21% (95% CI, 19–23%)) than the HIV-negative (9% (95% CI, 7–11%)) population. The number of HIV-positive TB notifications decreased mainly among 0- to 4- and 20- to 34-year-olds. Total population rates on ART at TB treatment initiation increased over time but levelled off in 2013. Overall median CD4 counts increased from 146 cells/µl (interquartile range (IQR), 66, 264) to 178 cells/µl (IQR 75, 330; p<0.001). Sub-district antenatal HIV seroprevalence differed (10–33%) as did numbers on ART (9–29 thousand). Across sub-districts, infant HIV-positive TB decreased consistently whereas adult decreases varied.

Conclusions

HIV-positive TB notification rates declined during a period of rapid scale-up of ART. Nevertheless, both HIV-positive and HIV-negative TB notification rates remained very high. Decreases among HIV positives were likely blunted by TB remaining a major entry to the ART programme and occurring after delayed ART initiation.     

The impact of patient demographics and comorbidities upon burns admitted to Tygerberg Hospital Burns Unit,Western Cape,South Africa

In South Africa, burns are a major public health problem responsible for significant morbidity and long-term physical disability. This is, in part, due to a significant proportion of the urban population living in poorly constructed, combustible accommodation. The presence of co-morbid diseases such as diabetes and malignancy in patients with burns has been associated with a poorer outcome. The impact of other diseases such as HIV has yet to be defined.A retrospective data collection study analysed the 221 patients admitted to Tygerberg Hospital Burns Unit in 2011 and the first six months of 2013. Using hospital records, patient demographic data was collected alongside burn agent, ICU admission, complications, and patient outcome in terms of length of stay and mortality.The most common burn agent was hot liquid (45.7%). A significant proportion of patients were subject to intentional attacks (34.3%). Shack fires and flame accounted cumulatively for 85% of total inhalational burns, the highest rates of admission to ICU (85.5%), the highest rate of complications, as well as 92.3% of all total fatalities. HIV+ patients had a higher mortality (13.3% vs 5%, p = 0.22) and a higher complication rate (46.7% vs 30%, p = 0.21). There was no difference in length of stay between the HIV+ and HIV− cohort (12 days vs. 15.5 days, p = 0.916).Burns are a significant yet preventable cause of mortality and morbidity. The rising number of shack fires, responsible for extensive burns and resultant mortality is concerning and indicates urgent attention and action. HIV complicates the recovery from burn and is responsible for an increased rate of in hospital mortality.