Publications by authors named "Tarylee Reddy"

55 Publications

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

Spat Spatiotemporal Epidemiol 2021 Jun 3;37:100413. Epub 2021 Feb 3.

Biostatistics Unit, South African Medical Research Council, Durban, Kwazulu-Natal, South Africa. Electronic address:

Generalized additive models (GAMs) were used to predict non-linear distributions of HIV prevalence and incidence based on semiparametric methods. The GAMs also provide smooth intensity maps by projecting the predicted HIV prevalence (or incidence) into the contour maps. Two sets of geo-coded data sources were used: (1) population-based cross-sectional data from 10,928 women who participated in four HIV behavioral surveys (2002-2017), (2) clinic-based longitudinal data from 7,557 women who resided in KwaZulu-Natal (2002-2016). Model estimated degrees of freedoms were 15.84,12.17,7.64 and 15.08 (2002-2012), indicating substantial spatial variations in HIV prevalence overtime. At localized-level these HIV incidence ranged from 15 to 18 per 100 person-year and scattered across the relatively homogeneous area within less than 100 km radius. These significant quantitative evidence were further supported by continuous-scale intensity maps. Our findings provided empirical and visual evidence for the changing face of the epidemic in South Africa using geospatial methods.
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http://dx.doi.org/10.1016/j.sste.2021.100413DOI Listing
June 2021

Subtype-specific differences in Gag-protease replication capacity of HIV-1 isolates from East and West Africa.

Retrovirology 2021 05 5;18(1):11. Epub 2021 May 5.

HIV Pathogenesis Programme, The Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa.

Background: The HIV-1 epidemic in sub-Saharan Africa is heterogeneous with diverse unevenly distributed subtypes and regional differences in prevalence. Subtype-specific differences in disease progression rate and transmission efficiency have been reported, but the underlying biological mechanisms have not been fully characterized. Here, we tested the hypothesis that the subtypes prevalent in the East Africa, where adult prevalence rate is higher, have lower viral replication capacity (VRC) than their West African counterparts where adult prevalence rates are lower.

Results: Gag-protease sequencing was performed on 213 and 160 antiretroviral-naïve chronically infected participants from West and East Africa respectively and bioinformatic tools were used to infer subtypes and recombination patterns. VRC of patient-derived gag-protease chimeric viruses from West (n = 178) and East (n = 114) Africa were determined using a green fluorescent protein reporter-based cell assay. Subtype and regional differences in VRC and amino acid variants impacting VRC were identified by statistical methods. CRF02_AG (65%, n = 139), other recombinants (14%, n = 30) and pure subtypes (21%, n = 44) were identified in West Africa. Subtypes A1 (64%, n = 103), D (22%, n = 35), or recombinants (14%, n = 22) were identified in East Africa. Viruses from West Africa had significantly higher VRC compared to those from East Africa (p < 0.0001), with subtype-specific differences found among strains within West and East Africa (p < 0.0001). Recombination patterns showed a preference for subtypes D, G or J rather than subtype A in the p6 region of gag, with evidence that subtype-specific differences in this region impact VRC. Furthermore, the Gag A83V polymorphism was associated with reduced VRC in CRF02_AG. HLA-A*23:01 (p = 0.0014) and HLA-C*07:01 (p = 0.002) were associated with lower VRC in subtype A infected individuals from East Africa.

Conclusions: Although prevalent viruses from West Africa displayed higher VRC than those from East Africa consistent with the hypothesis that lower VRC is associated with higher population prevalence, the predominant CRF02_AG strain in West Africa displayed higher VRC than other prevalent strains suggesting that VRC alone does not explain population prevalence. The study identified viral and host genetic determinants of virus replication capacity for HIV-1 CRF02_AG and subtype A respectively, which may have relevance for vaccine strategies.
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http://dx.doi.org/10.1186/s12977-021-00554-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8097975PMC
May 2021

Effects  of rural-urban residence and education on intimate partner violence among women in Sub-Saharan Africa: a meta-analysis of health survey data.

BMC Womens Health 2021 04 13;21(1):149. Epub 2021 Apr 13.

Biostatistics Research Unit, South African Medical Research Council, Durban, South Africa.

Background: Intimate Partner Violence (IPV) against women is a major public health and human rights problem worldwide. Sub-Saharan Africa (SSA) has one of the highest prevalence of IPV against women in the world. This study used meta-analysis to obtain pooled rural-urban and education attainment differences in the prevalence of IPV among ever-partnered women in SSA, and assessed whether the differences in IPV depended on the SSA region or period or women's age.

Methods: We analysed IPV data on 233,585 ever-partnered women aged 15-49 years from 44 demographic and health surveys conducted between 2000 and 2018 in 29 SSA countries. Random-effects meta-analyses were used to estimate overall rural-urban residence and educational differences in IPV rates among the women in SSA. Subgroup analyses were also done to investigate the sources of heterogeneity in the overall meta-analysis findings.

Results: The pooled prevalence of intimate partner violence was estimated to be 41.3% (37.4-45.2%). Regionally, the highest prevalence of IPV was in Middle Africa (49. 3%; 40.32-58.45), followed by East Africa (44.13%; 36.62-51.67), Southern Africa (39.36%; 34.23-44.49), and West Africa (34.30%; 27.38-41.22). The risks of experiencing IPV were significantly higher if the women had less than secondary education (RR = 1.12; 95% CI  1.07-1.22) compared to those with at least a secondary education. Generally, women who resided in a rural area had their risks of experiencing IPV increased (RR = 1.02; CI 0.96-1.06) compared to those who resided in urban areas, but the IPV increases were only significant in East Africa (RR = 1.13; CI 1.07-1.22).

Conclusion: In sub-Saharan Africa, intimate partner violence against women is widespread, but the levels are much higher among women with lower levels of education and residing in rural areas. Our findings have provided additional support to policies aimed at achieving SDG goals on the elimination of all forms of violence against women and girls in sub-Saharan Africa. For example, policies that advocate improved educational attainment, especially among women and communities in rural areas.
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http://dx.doi.org/10.1186/s12905-021-01286-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8045348PMC
April 2021

Quantifying geographical diversity in sexually transmitted infections using population attributable risk: results from HIV prevention trials in South Africa.

Int J STD AIDS 2021 Jun 26;32(7):600-608. Epub 2021 Mar 26.

Biostatistics Unit, South African Medical Research Council, Durban, South Africa.

In this study, we investigated spatial diversities of sexually transmitted infections (STIs) and quantified their impacts on the STIs using population attributable risk (PAR%). The study population was 7,557 women who participated in several HIV prevention trials from KwaZulu-Natal, South Africa. Our results provide compelling evidence for substantial geographical diversities on STI incidence rates in the region. Their population-level impacts on the STIs exceeded the combined impacts of the individual risk factors considered in this study (PAR%: 41% (<25 years), 52% (25-34 years) and 34% (35+ years). When all these factors are considered together, PAR% was the highest among younger women (PAR%: 67%, 82% and 50% for <25, 25-34 and 35+ years old respectively). Results from our study will bring greater insight into the previous research by increasing our understanding of the impacts of the sub-geographical level variations of STI prevalence and incidence rates in the region.
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http://dx.doi.org/10.1177/0956462420968998DOI Listing
June 2021

Short-term real-time prediction of total number of reported COVID-19 cases and deaths in South Africa: a data driven approach.

BMC Med Res Methodol 2021 01 11;21(1):15. Epub 2021 Jan 11.

Biostatistics Research Unit, South African Medical Research Council, Cape Town, South Africa.

Background: The rising burden of the ongoing COVID-19 epidemic in South Africa has motivated the application of modeling strategies to predict the COVID-19 cases and deaths. Reliable and accurate short and long-term forecasts of COVID-19 cases and deaths, both at the national and provincial level, are a key aspect of the strategy to handle the COVID-19 epidemic in the country.

Methods: In this paper we apply the previously validated approach of phenomenological models, fitting several non-linear growth curves (Richards, 3 and 4 parameter logistic, Weibull and Gompertz), to produce short term forecasts of COVID-19 cases and deaths at the national level as well as the provincial level. Using publicly available daily reported cumulative case and death data up until 22 June 2020, we report 5, 10, 15, 20, 25 and 30-day ahead forecasts of cumulative cases and deaths. All predictions are compared to the actual observed values in the forecasting period.

Results: We observed that all models for cases provided accurate and similar short-term forecasts for a period of 5 days ahead at the national level, and that the three and four parameter logistic growth models provided more accurate forecasts than that obtained from the Richards model 10 days ahead. However, beyond 10 days all models underestimated the cumulative cases. Our forecasts across the models predict an additional 23,551-26,702 cases in 5 days and an additional 47,449-57,358 cases in 10 days. While the three parameter logistic growth model provided the most accurate forecasts of cumulative deaths within the 10 day period, the Gompertz model was able to better capture the changes in cumulative deaths beyond this period. Our forecasts across the models predict an additional 145-437 COVID-19 deaths in 5 days and an additional 243-947 deaths in 10 days.

Conclusions: By comparing both the predictions of deaths and cases to the observed data in the forecasting period, we found that this modeling approach provides reliable and accurate forecasts for a maximum period of 10 days ahead.
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http://dx.doi.org/10.1186/s12874-020-01165-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7797353PMC
January 2021

Characteristics of women who use hormonal contraceptives and their population-level impacts on HIV infection in a cohort of South African women (2002-2016).

Eur J Contracept Reprod Health Care 2020 Dec;25(6):449-455

Biostatistics Unit, South African Medical Research Council, Durban, South Africa.

Purpose: Women's choice of contraceptive can have broader implications and may play a significant role in shaping their sexual practices. We aim to identify the characteristics of women who use hormonal injectables and those at high-risk of HIV infection. We also quantify the population-level impact of their shared characteristics on HIV incidence rates.

Materials And Methods: Data from 9948 women who enrolled in six-HIV prevention trials conducted in South Africa (2002-2016) were included. We used logistic and Cox regression models and estimated the population-level impact of the use of injectables on HIV incidence in the multifactorial-model setting.

Results: Using hormonal injectables were associated with increased risk of HIV infection (adjusted Hazard ratio (aHR):1.51, 95% CI:1.22, 1.86). At the population level less than 20% of the infections were associated with injectable contraceptives among younger women (i.e., less than 35 years of age). Factors including being single/not-cohabiting, using condoms at last sex, partner-related factors, and STI diagnosis were all identified as shared characteristics of women who preferred using hormonal injectables and those at high-risk of HIV infection. At the population level, these factors were associated with more than 50% of the infections among women younger than 35 years of age.

Conclusions: Our analysis presented evidence for the overlapping characteristics of the women who used hormonal injectables and those at high-risk of HIV infection. These findings reinforce the importance of comprehensive contraceptive counselling to women about the importance of dual protection, such as male condoms and hormonal contraceptives use.
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http://dx.doi.org/10.1080/13625187.2020.1831469DOI Listing
December 2020

The Impact of Male Partner Circumcision on Women's Health Outcomes.

AIDS Educ Prev 2020 08;32(4):356-366

HIV Prevention Research Unit, South African Medical Research Council, Cape Town, South Africa.

Medical male circumcision is a proven method of HIV risk reduction in men with no known direct benefit to women. We investigated the benefit of partner circumcision on women's health. We conducted a secondary analysis of 5,029 women enrolled in the Vaginal and Oral Interventions to Control the Epidemic trial across 15 African sites, to look at the impact of partner circumcision status on sexually transmitted infections, pregnancy, frequency of sex, and condom use in women. Of 4,982 participants with a baseline response, 31% had circumcised partners. Women with circumcised partners had a significantly reduced risk of syphilis acquisition, hazard ratio 0.51 (0.26, 1.00), value = .05. Participants with uncircumcised partners were significantly less likely to have used a condom at the last sex act than the other two groups, adj. relative risk 0.86 (0.80, 0.92), adj. value < .0001. We found no evidence of sexual risk compensation in women with circumcised partners.
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http://dx.doi.org/10.1521/aeap.2020.32.4.356DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585933PMC
August 2020

Non-partner sexual violence experience and toilet type amongst young (18-24) women in South Africa: A population-based cross-sectional analysis.

Glob Public Health 2021 Apr 8;16(4):590-596. Epub 2020 Sep 8.

Epicentre, Durban, South Africa.

Inadequate toilet facilities may increase women's risk of experiencing non-partner sexual violence. We sought to assess the association between young (18-24 year-olds) women's access to toilets and past year non-partner rape experience, in deprived communities in South Africa. Data came from cross-sectional, population-based survey from poor communities from four health districts in two provinces, namely, City of Johannesburg, and Ekurhuleni in Gauteng, and eThekwini and uMgungundlovu, in KwaZulu-Natal. Descriptive, unadjusted and adjusted associations, were estimated in STATA/IC16, accounting for study design. In total, 10,635 young women provided data on toilet access. Past year non-partner rape prevalence was 5.7%. In adjusted analyses, those reporting a shared toilet were more likely to report past year experience of non-partner rape (adjusted odds ratio: 1.45, 95% confidence intervals [1.17, 1.80]), compared to those with their own toilet indoors. Improving access to private, secure toilets is an important component for the prevention of non-partner sexual violence.
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http://dx.doi.org/10.1080/17441692.2020.1813787DOI Listing
April 2021

Estimating prevalence and incidence of sexually transmitted infections among South African women: Implications of combined impacts of risk factors.

Int J STD AIDS 2020 10 3;31(11):1093-1101. Epub 2020 Sep 3.

HIV Prevention Unit, South African Medical Research Council, Durban, South Africa.

In addition to being the epicentre of the HIV epidemic, South Africa also has the highest burden of sexually transmitted infections (STIs) in the world. Therefore, understanding the most influential risk factors of STIs is a research priority. Using the data from 9948 women who resided in KwaZulu Natal, South Africa, we estimated the population attributable risk to quantify the combined impacts of the most influential factors on STI diagnosis. Overall STI prevalence was 20%, and STI incidence was 15 per 100 person-years. Four factors: age at sexual debut, single/not cohabiting, two or more sex partners and parity <3 were identified as the most influential risk factors for STI prevalence and incidence rates. However, these factors collectively associated with only 51% and 53% of the excess STI prevalence and incidence rates, respectively. These relatively modest impacts provide empirical evidence for the significant impacts of unmeasured factors on STIs. Culturally and socially appropriate prevention programs may be more effective to target those at highest risk of STIs.
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http://dx.doi.org/10.1177/0956462420915388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8032503PMC
October 2020

Exposure to lead and other toxic metals from informal foundries producing cookware from scrap metal.

Environ Res 2020 12 5;191:109860. Epub 2020 Aug 5.

South African Medical Research Council Durban, South Africa.

Metal exposure remains a significant public health problem, particularly in the informal sector. The rise in informal foundries to cast scrap metal into artisanal cookware is widespread in low- and middle-income countries. The main aim of this study was to characterize metal exposure in artisanal cookware makers working in informal foundries in South Africa by measuring lead (Pb) in blood as well as sample metal concentrations on hands before and after work. The blood Pb distribution of the artisanal pot makers ranged from 1.1 to 4.6 μg/dl with the median blood Pb level being 2.1 μg/dl (IQR 1.7-2.5). The median blood Pb level in artisanal pot makers was 1.0 μg/dl higher compared with the non-exposed community members (p < 0.0001). Before-and-after handwipe sampling revealed a median increase in all 22 elements. Pre and post aluminum (Al) load on the handwipes revealed a 7.3 factor increase (0.53 and 3.9 mg Al/handwipe respectively) (p = 0.003). Hand Pb load before and after pot making revealed a 3.5-fold increase (median increase of 6.2 μg Pb/handwipe). An increase in backyard informal foundries may be linked to increased exposure to toxic metals for workers, family members and communities.
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http://dx.doi.org/10.1016/j.envres.2020.109860DOI Listing
December 2020

Temporal trends in sexual behaviours and their impacts on HIV incidence among South African women: 2002-2016.

AIDS Care 2020 Jul 23:1-7. Epub 2020 Jul 23.

South African Medical Research Council, HIV Prevention Research Unit, Durban, South Africa.

South Africa has the highest number of HIV infected individuals in the world. The primary objective of the current study was to describe temporal changes in HIV incidence rates using the data from 9,948 women who enrolled in one of the six HIV prevention trials conducted in KwaZulu-Natal, South Africa. Characteristics of the study population were presented and compared across the four study periods: 2002-2004, 2005-2008, 2009-2011 and 2012-2016. HIV infection rates increased from 6.2 to 9.3 per 100 person-year over the 15 years. These rates were as high as 14 per 100 person-year among women younger than 20 years age. Being single/not cohabiting, using injectable contraceptives, having less than two children, and diagnosed with STI(s) were associated with increased risk of HIV infection. These four factors were associated with 71%, 75%, 80% and 88% of the HIV seroconversions in four study periods. As the research continues to find ways of controlling the spread of the infections, quantifying the temporal trends in risk factors and their population-level impacts on HIV infection may have significant implications. This information may assist in developing effective counselling and education programs by targeting the sexually active single women and delivering more realistic messages.
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http://dx.doi.org/10.1080/09540121.2020.1789054DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8058034PMC
July 2020

Contraceptives and sexual behaviours in predicting pregnancy rates in HIV prevention trials in South Africa: Past, present and future implications.

Sex Reprod Healthc 2020 Dec 18;26:100531. Epub 2020 May 18.

South African Medical Research Council, HIV Prevention Research Unit, Durban, Kwazulu-Natal, South Africa; Aurum Global Department: Health Research, Durban, Kwazulu-Natal, South Africa.

Objective: Despite all efforts, high pregnancy rates are often reported in HIV biomedical intervention trials conducted in African countries. We therefore aimed to develop a pregnancy risk scoring algorithm for targeted recruitment and screening strategies among a cohort of women in South Africa.

Methods: The study population was ~ 10,000 women who enrolled in one of the six biomedical intervention trials conducted in KwaZulu Natal, South Africa. Cox regression models were used to create a pregnancy risk scoring algorithm which was internally validated using standard statistical measures.

Results: Five factors were identified as significant predictors of pregnancy incidence:<25 years old, not using injectable contraceptives, parity (<3), being single/not cohabiting and having ≥ 2 sexual partners in the past three months. Women with total scores of 21-24, 25-35 and 36+ were classified as being at "moderate", "high", "severe" risk of pregnancy. Sensitivity of the development and validation models were reasonably high (sensitivity 76% and 74% respectively).

Conclusion: Our risk scoring algorithm can identify and alert researchers to women who need additional non-routine pregnancy assessment and counselling, with statistically acceptable accuracy and robustness.
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http://dx.doi.org/10.1016/j.srhc.2020.100531DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8032504PMC
December 2020

Joint modelling of longitudinal and time-to-event data: an illustration using CD4 count and mortality in a cohort of patients initiated on antiretroviral therapy.

BMC Infect Dis 2020 Mar 30;20(1):256. Epub 2020 Mar 30.

Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, 719 Umbilo Road, Durban, 4041, South Africa.

Background: Modelling of longitudinal biomarkers and time-to-event data are important to monitor disease progression. However, these two variables are traditionally analyzed separately or time-varying Cox models are used. The former strategy fails to recognize the shared random-effects from the two processes while the latter assumes that longitudinal biomarkers are exogenous covariates, resulting in inefficient or biased estimates for the time-to-event model. Therefore, we used joint modelling for longitudinal and time-to-event data to assess the effect of longitudinal CD4 count on mortality.

Methods: We studied 4014 patients from the Centre for the AIDS Programme of Research in South Africa (CAPRISA) who initiated ART between June 2004 and August 2013. We used proportional hazards regression model to assess the effect of baseline characteristics (excluding CD4 count) on mortality, and linear mixed effect models to evaluate the effect of baseline characteristics on the CD4 count evolution over time. Thereafter, the two analytical approaches were amalgamated to form an advanced joint model for studying the effect of longitudinal CD4 count on mortality. To illustrate the virtues of the joint model, the results from the joint model were compared to those from the time-varying Cox model.

Results: Using joint modelling, we found that lower CD4 count over time was associated with a 1.3-fold increase in the risk of death, (HR: 1.34, 95% CI: 1.27-1.42). Whereas, results from the time-varying Cox model showed lower CD4 count over time was associated with a 1.2-fold increase in the risk of death, (HR: 1.17, 95% CI: 1.12-1.23).

Conclusions: Joint modelling enabled the assessment of the effect of longitudinal CD4 count on mortality while correcting for shared random effects between longitudinal and time-to-event models. In the era of universal test and treat, the evaluation of CD4 count is still crucial for guiding the initiation and discontinuation of opportunistic infections prophylaxis and assessment of late presenting patients. CD4 count can also be used when immunological failure is suspected as we have shown that it is associated with mortality.
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http://dx.doi.org/10.1186/s12879-020-04962-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7106785PMC
March 2020

Respiratory outcomes among plant processing workers in Durban, South Africa.

Int J Occup Saf Ergon 2020 May 5:1-5. Epub 2020 May 5.

Environment and Health Research Unit, South African Medical Research Council, South Africa.

Plant products used by informal traditional medicine traders go through various methods of manual processing to yield a final single or multi-concoction product; however, the prevalence of potentially associated respiratory outcomes has yet to be established. The aim of this study was to describe respiratory outcomes associated with processing plants among informal traditional medicine traders. Questionnaires related to the preparation of plant products and respiratory outcomes were administered to study participants by trained researchers. Of the 216 traders, nocturnal cough, nasal allergies and waking with a feeling of tightness in the chest were the most frequently cited respiratory outcomes (43, 35 and 22%, respectively). The study highlighted the burden of respiratory outcomes among traders who process plant products and the need for targeted workplace interventions.
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http://dx.doi.org/10.1080/10803548.2020.1748840DOI Listing
May 2020

HIV-Prevalence in South Africa by settlement type: A repeat population-based cross-sectional analysis of men and women.

PLoS One 2020 17;15(3):e0230105. Epub 2020 Mar 17.

Gender and Health Research Unit, South African Medical Research Council, Pretoria, South Africa.

To assess i) whether there is an independent association between HIV-prevalence and settlement types (urban formal, urban informal, rural formal, rural informal), and, ii) whether this changes over time, in South Africa. We draw on four (2002; 2005; 2008; 2012) cross-sectional South African household surveys. Data is analysed by sex (male/female), and for women by age categories (15-49; and 15-24; 25-49) at all-time points, for men in 2012 data is analysed by age categories (15-24; 25-49). By settlement type and sex/age combinations, we descriptively assess the association between socio-demographic and HIV-risk factors; HIV-prevalence; and trends in HIV-prevalence by time. Relative risk ratios assess unadjusted and adjusted risk for HIV-prevalence by settlement type. All estimates are weighted, and account for survey design. In all survey years, and combinations of sex/age categorisations, HIV-prevalence is highest in urban informal settlements. For men (15-49) an increasing HIV-prevalence over time in rural informal settlements was seen (p = 0.001). For women (15-49) HIV-prevalence increases over time for urban informal, rural informal, rural formal, and women (15-24) decreases in urban formal and urban informal, and women (25-49) increases urban informal and rural informal settlements. In analyses adjusting for potential socio-demographic and risk factors, compared to urban formal settlements, urban informal settlements had consistently higher relative risk of HIV for women, in all age categorisations, for instance in 2012 this was RR1.89 (1.50, 2.40) for all women (15-49), for 15-24 (RR1.79, 1.17-2.73), and women 25-49 (RR1.91, 1.47-2.48). For men, in the overall age categorization, urban informal settlements had a higher relative risk for HIV in all years. In 2012, when this was disaggregated by age, for men 15-24 rural informal (IRR2.69, 1.28-5.67), and rural formal (RR3.59, 1.49-8.64), and for men 25-49 it was urban informal settlements with the highest (RR1.68, 1.11-2.54). In 2012, rural informal settlements also had higher adjusted relative risk for HIV-prevalence for men (15-49) and women (15-49; 15-24; 25-49). In South Africa, HIV-prevalence is patterned geographically, with urban informal settlements having a particularly high burden. Geographical targeting of responses is critical for the HIV-response.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0230105PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7077822PMC
June 2020

Cardiac Doppler in poorly controlled gestational diabetics and its link to markers of intra-uterine hypoxia and adverse outcome.

J Obstet Gynaecol 2021 Jan 9;41(1):66-72. Epub 2020 Mar 9.

Biostatistics Unit, South African Medical Research Council of South Africa, Durban, South Africa.

The aim of the study was to investigate foetal cardiac function using the modified myocardial performance index (Mod-MPI) in poorly controlled gestational diabetics and its link with intrauterine markers for hypoxia and to an adverse outcome. In a prospective, cross sectional study, 44 consecutive women with severe or poorly controlled gestational diabetic pregnancies in their third trimester on insulin therapy were recruited and matched with 44 women with normal pregnancies which served as the control group. Using Doppler echocardiography the foetal Mod-MPI was calculated. The foetal Mod-MPI was significantly higher in the diabetic group compared to the controls indicating significant myocardial dysfunction. The Mod-MPI served as an excellent marker of adverse outcomes. Foetal myocardial function was significantly impaired in poorly controlled gestational diabetics and there was a significant link of Mod-MPI to intrauterine markers of hypoxia, as well as to an adverse outcome. Mod-MPI has the potential to improve foetal surveillance in gestational diabetes.IMPACT STATEMENT Abnormal foetal cardiac function, as reflected in the modified myocardial performance index, has been reported to be significantly increased in foetuses of poorly controlled diabetics managed on insulin. There is a significant link between abnormal foetal cardiac function to intrauterine markers of hypoxia, as well as to an adverse outcome; and that development of myocardial dysfunction could be one of the main mechanisms, inducing foetal compromise in poorly controlled gestational diabetes. This study explores an interesting concept of foetal pathophysiology in gestational diabetes, namely the concept of "pseudo-hypoxia" in a foetus of a gestational diabetic mother, and this intrauterine "hypoxic stress" in turn leading to myocardial dysfunction. The Mod-MPI, a clinical marker for cardiac dysfunction, can therefore be used in the clinical setting to track a deteriorating metabolic state.
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http://dx.doi.org/10.1080/01443615.2019.1710480DOI Listing
January 2021

Maternal and Infant Outcomes Among Pregnant Women Treated for Multidrug/Rifampicin-Resistant Tuberculosis in South Africa.

Clin Infect Dis 2021 04;72(7):1158-1168

Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Stellenbosch University, South Africa.

Background: Data on safety and efficacy of second-line tuberculosis drugs in pregnant women and their infants are severely limited due to exclusion from clinical trials and expanded access programs.

Methods: Pregnant women starting treatment for multidrug/rifampicin-resistant (MDR/RR)-tuberculosis at King Dinuzulu Hospital in KwaZulu-Natal, South Africa, from 1 January 2013 to 31 December 2017, were included. We conducted a record review to describe maternal treatment and pregnancy outcomes, and a clinical assessment to describe infant outcomes.

Results: Of 108 pregnant women treated for MDR/RR-tuberculosis, 88 (81%) were living with human immunodeficiency virus.. Favorable MDR/RR-tuberculosis treatment outcomes were reported in 72 (67%) women. Ninety-nine (91%) of the 109 babies were born alive, but overall, 52 (48%) women had unfavorable pregnancy outcomes. Fifty-eight (54%) women received bedaquiline, and 49 (45%) babies were exposed to bedaquiline in utero. Low birth weight was reported in more babies exposed to bedaquiline compared to babies not exposed (45% vs 26%; P = .034). In multivariate analyses, bedaquiline and levofloxacin, drugs often used in combination, were both independently associated with increased risk of low birth weight. Of the 86 children evaluated at 12 months, 72 (84%) had favorable outcomes; 88% of babies exposed to bedaquiline were thriving and developing normally compared to 82% of the babies not exposed.

Conclusions: MDR/RR-tuberculosis treatment outcomes among pregnant women were comparable to nonpregnant women. Although more babies exposed to bedaquiline were of low birth weight, over 80% had gained weight and were developing normally at 1 year.
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http://dx.doi.org/10.1093/cid/ciaa189DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8028100PMC
April 2021

Assessment of the Impact of Rapid Point-of-Care CD4 Testing in Primary Healthcare Clinic Settings: A Survey Study of Client and Provider Perspectives.

Diagnostics (Basel) 2020 Feb 1;10(2). Epub 2020 Feb 1.

South African Medical Research Council, Durban 4000, South Africa.

Background: The high burden of disease in South Africa presents challenges to public health services. Point-of-care (POC) technologies have the potential to address these gaps and improve healthcare systems. This study ascertained the acceptability and impact of POC CD4 testing on patients' health and clinical management.

Methods: We conducted a qualitative survey study with patients ( = 642) and healthcare providers ( = 13) at the Lancers Road (experienced POC) and Chesterville (non-experienced POC) primary healthcare (PHC) clinics from September 2015 to June 2016.

Results: Patients (99%) at Lancers and Chesterville PHCs were positive about POC CD4 testing, identifying benefits: No loss/delay of test results (6.4%), cost/time saving (19.5%), and no anxiety (5.1%), and 58.2% were ready to initiate treatment. Significantly more patients at Chesterville than Lancers Road PHC felt POC would provide rapid clinical decision making (64.7% vs. 48.1%; < 0.0001) and better clinic accessibility (40.4% vs. 24.7%; < 0.0001) respectively. Healthcare providers thought same-day CD4 results would impact: Clinical management (46.2%), patient readiness (46.2%), and adherence (23.0%), and would reduce follow-up visits (7.7%), while 38.5% were concerned that further tests and training (15.4%) were required before antiretroviral therapy (ART) initiation.

Conclusion: The high acceptability of POC CD4 testing and the immediate health, structural, and clinical management benefits necessitates POC implementation studies.
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http://dx.doi.org/10.3390/diagnostics10020081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7168920PMC
February 2020

Evaluating DREAMS HIV prevention interventions targeting adolescent girls and young women in high HIV prevalence districts in South Africa: protocol for a cross-sectional study.

BMC Womens Health 2020 01 16;20(1). Epub 2020 Jan 16.

Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, KwaZulu-Natal, South Africa.

Background: Young women in sub-Saharan Africa remain at the epicentre of the HIV epidemic, with surveillance data indicating persistent high levels of HIV incidence. In South Africa, adolescent girls and young women (AGYW) account for a quarter of all new HIV infections. Determined, Resilient, Empowered, AIDS-free, Mentored and Safe (DREAMS) is a strategy introduced by the United States President's Emergency Plan for AIDS Relief (PEPFAR) aimed at reducing HIV incidence among AGYW in 10 countries in sub-Saharan Africa by 25% in the programme's first year, and by 40% in the second year. This study will assess the change in HIV incidence and reduction in risk associated behaviours that can be attributed to the DREAMS initiative in South Africa, using a population-based cross-sectional survey.

Methods: Data will be collected from a household-based representative sample of AGYW (between the ages 12-24 years) in four high prevalence districts (more than 10% of the population have HIV in these districts) in South Africa in which DREAMS has been implemented. A stratified cluster-based sampling approach will be used to select eligible participants for a cross-sectional survey with 18,500, to be conducted over 2017/2018. A questionnaire will be administered containing questions on sexual risk behaviour, selected academic and developmental milestones, prevalence of gender based violence, whilst examining exposure to DREAMS programmes. Biological samples, including two micro-containers of blood and self-collected vulvovaginal swab samples, are collected in each survey to test for HIV infection, HIV incidence, sexually transmitted infections (STIs) and pregnancy. This study will measure trends in population level HIV incidence using the Limiting antigen (LAg) Avidity Enzyme Immuno-Assay (EIA) and monitor changes in HIV incidence.

Discussion: Ending the HIV/AIDS pandemic by 2030 requires the continual monitoring and evaluation of prevention programmes, with the aim of optimising efforts and ensuring the achievement of epidemic control. This study will determine the impact DREAMS interventions have had on HIV incidence among AGYW in a 'real world, non-trial setting'.
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http://dx.doi.org/10.1186/s12905-019-0875-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6966796PMC
January 2020

Evaluation of a health system intervention to improve virological management in an antiretroviral programme at a municipal clinic in central Durban.

South Afr J HIV Med 2019 26;20(1):985. Epub 2019 Sep 26.

HIV Prevention Research Unit, South African Medical Research Council, Durban, South Africa.

Background: With the largest antiretroviral therapy (ART) programme globally, demand for effective HIV management is increasing in South Africa. While viral load (VL) testing is conducted, VL follow-up and management are sub-optimal.

Objectives: The objective of this study was to address gaps in the VL cascade to improve VL testing and management.

Methods: Antiretroviral therapy records were sampled for an in-depth review. The study team then reviewed individual records, focusing on ART management, virological suppression and retention. Multifaceted interventions focused on virological control, including a clinical summary chart for ART care; streamlining laboratory results receipt and management; monitoring VL suppression, flagging virological failure and missed visits for follow-up; down-referral of stable patients eligible for the chronic club system; and training of personnel and patients.

Results: Pre-intervention, 78% (94/120) of eligible patients had VL tests, versus 92% (145/158) post-intervention ( = 0.0009). Pre-intervention, 59% (71/120) of patients accessed their VL results, versus 86% (136/158) post-intervention ( < 0.0001). Post-intervention, 73% (19/26) of patients eligible for ART change were appropriately managed, versus 11% (4/36) pre-intervention ( < 0.0001). Only 27% had no regimen changes (7/26) post-intervention, versus 81% (29/36) pre-intervention ( < 0.0001).

Conclusion: Service delivery was streamlined to facilitate HIV services by focusing on VL test monitoring, protocol training and accessibility of results, thereby improving clinical management.
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http://dx.doi.org/10.4102/sajhivmed.v20i1.985DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6779997PMC
September 2019

Investigating spatial disparities in high-risk women and HIV infections using generalized additive models: Results from a cohort of South African women.

Spat Spatiotemporal Epidemiol 2019 08 29;30:100283. Epub 2019 May 29.

HIV Prevention Research Unit, South African Medical Research Council, Westville, 3630 KwaZulu-Natal, South Africa; Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK; Department of Global Health, School of Medicine, University of Washington, United States. Electronic address:

Objective: We identified the geographical clustering of HIV as well as those at highest risk of infection using a decade long data (2002-2012) from KwaZulu-Natal, South Africa.

Methods: A total of 5,776 women who enrolled in several HIV prevention trials were included in the study. Geo-coded individual-level data were linked to the community-level characteristics using the South African Census. High-risk women were identified using a risk scoring algorithm. Generalized additive models were used to identify the significant geographical clustering of high-risk women and HIV.

Results: Overall, 60% of the women were classified as high risk of HIV. HIV infection rates were estimated as high as 10 to 15 per 100 person year. Areas with high rates of HIV infections were spatially clustered and overlapped particularly in the Northern part of Durban.

Conclusion: Targeting multifactorial and complex nature of the epidemic is urgently needed to identify the "high transmission" areas.
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http://dx.doi.org/10.1016/j.sste.2019.100283DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6914769PMC
August 2019

Assessment of the Fetal Myocardial Performance Index in Well-Controlled Gestational Diabetics and to Determine Whether It Is Predictive of Adverse Perinatal Outcome.

Pediatr Cardiol 2019 Oct 19;40(7):1460-1467. Epub 2019 Jul 19.

Biostatistics Unit, South African Medical Research Council of South Africa, Durban, South Africa.

This study was aimed at determining if the myocardial performance index (MPI) is altered in well-controlled gestational diabetics and if so whether it is predictive of adverse perinatal outcome. In a prospective cross-sectional study, 54 consecutive women with well-controlled gestational diabetes controlled on insulin or metformin in the third trimester were recruited and matched with 54 women with normal pregnancies (control group). Using Doppler echocardiography, the MPI was calculated. Sonographic biophysical and placental resistance Doppler markers in both groups were also determined. An abnormal outcome was defined as any of the following: stillbirth; neonatal death; neonatal intensive care admissions; tachypnea with pulmonary edema; neonatal cord pH < 7.15; 5-min Apgar score < 7, polycythemia; and nucleated red blood cells > 10/100 white blood cell counts, hypoglycemia. The MPI was significantly higher in the diabetic group compared to controls (p < 0.0001). Rate of adverse outcome was 22% in the diabetic group. The diabetic group with adverse outcomes had significantly elevated MPI values compared to the diabetic group with normal outcomes. There were 26 diabetics controlled on metformin and 28 controlled on insulin. The adverse outcome rate was slightly higher in the IDDM group compared to the non-insulin-dependent group but was not statistically significant. The main adverse outcomes were low Apgars (18%), hypoglycemia (22%), polycythemia (13%) and low pH in 7%. All control births had normal outcomes. MPI served as an independent predictor of adverse outcome. The MPI z-score had a good diagnostic accuracy as evidenced by the area under the ROC curve of 0.83. An MPI z-score exceeding 4.55 conferred a 90% sensitivity and 74% specificity, with 77% of outcomes correctly classified with a likelihood ratio of 3.5. The MPI is impaired in fetuses in well-controlled gestational diabetes, with fetuses with an adverse outcome having significantly higher MPI values compared to the fetuses with normal outcome in the diabetic group. MPI has the potential to improve fetal surveillance in gestational diabetes.
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http://dx.doi.org/10.1007/s00246-019-02158-4DOI Listing
October 2019

Random effects models for estimation of the probability and time to progression of a continuous biomarker.

Pharm Stat 2019 11 15;18(6):671-687. Epub 2019 Jul 15.

Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands.

Biomarkers play a key role in the monitoring of disease progression. The time taken for an individual to reach a biomarker exceeding or lower than a meaningful threshold is often of interest. Due to the inherent variability of biomarkers, persistence criteria are sometimes included in the definitions of progression, such that only two consecutive measurements above or below the relevant threshold signal that "true" progression has occurred. In previous work, a novel approach was developed, which allowed estimation of the time to threshold using the parameters from a linear mixed model where the residual variance was assumed to be pure measurement error. In this paper, we extend this methodology so that serial correlation can be accommodated. Assuming that the Markov property holds and applying the chain rule of probabilities, we found that the probability of progression at each timepoint can be expressed simply as the product of conditional probabilities. The methodology is applied to a cohort of HIV positive individuals, where the time to reach a CD4 count threshold is estimated. The second application we present is based on a study on abdominal aortic aneurysms, where the time taken for an individual to reach a diameter exceeding 55 mm is studied. We observed that erroneously ignoring the residual correlation when it is strong may result in substantial overestimation of the time to threshold. The estimated probability of the biomarker reaching a threshold of interest, expected time to threshold, and confidence intervals are presented for selected patients in both applications.
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http://dx.doi.org/10.1002/pst.1956DOI Listing
November 2019

Point-of-care HIV testing best practice for early infant diagnosis: an implementation study.

BMC Public Health 2019 Jun 11;19(1):731. Epub 2019 Jun 11.

Department of Paediatrics and Child Health, School of Clinical Medicine, University of KwaZulu-Natal, Durban, South Africa.

Background: With Universal Health Coverage and Integrated People-centred Health Care, streamlined health-systems and respectful care are necessary. South Africa has made great strides in prevention of mother-to-child transmission (PMTCT) but with the great burden of HIV, a minimum of birth and 10-week HIV-PCR testing are required for the estimated 360,000 HIV-exposed infants born annually which presents many challenges including delayed results and loss to follow-up. Point-of-care (POC) HIV testing of infants addresses these challenges well and facilitates initiation of HIV-infected infants rapidly after diagnosis for best clinical outcomes.

Methods: Objectives were to determine accuracy, feasibility and acceptability of POC testing compared to standard-of-care (SOC) central-laboratory testing. HIV-exposed infants for birth PCR testing in hospital (n = 323) and follow-up at a primary health care clinic (n = 117) in Durban, South Africa were included. A baseline situational-analysis reviewed registers and phoned mothers of HIV-exposed infants prior to the intervention. An effectiveness-implementation study of the Alere™q HIV-1/2 Detect POC test (heel-prick specimen processed in 50 min) was compared with SOC with questionnaires to mothers and staff. Stata 14 was used for analysis.

Results: At baseline 2% of birth HIV tests were missed; only 40% of mothers could be contacted; 17% did not receive birth test result; 19% did not have a 10-week test; 39% had not received the 10-week results. There were 5(1.5%) HIV-infected and 318(98.5%) HIV-negative infants detected in hospital with all clinic babies negative. All positive infants commenced ART before discharge. Ultimately POC and SOC had perfect concordance but for 10 SOC tests researchers actively tracked-down results or repeated tests. Turn around times for SOC tests were on average 8-days (IQR 6-10  days) and for POC testing was 0-days. The POC error-rate was 9,6% with all giving a result when repeated. The majority of mothers (92%) preferred POC testing with 7% having no preference. No staff preferred SOC testing with 79% preferring POC and 21% having no preference.

Conclusions: Point-of-care HIV testing for EID is accurate, feasible and acceptable, with benefits of early ART for all positive infants at birth facilities. We recommend that it be considered best practice for EID.

Trial Registration: ISRCTN38911104 registered 9 January 2018 - retrospectively registered.
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http://dx.doi.org/10.1186/s12889-019-6990-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6560857PMC
June 2019

A decade of sustained geographic spread of HIV infections among women in Durban, South Africa.

BMC Infect Dis 2019 Jun 7;19(1):500. Epub 2019 Jun 7.

School of Nursing and Public Health, University of KwaZulu-Natal, Kwazulu-Natal, Durban, South Africa.

Background: Fine scale geospatial analysis of HIV infection patterns can be used to facilitate geographically targeted interventions. Our objective was to use the geospatial technology to map age and time standardized HIV incidence rates over a period of 10 years to identify communities at high risk of HIV in the greater Durban area.

Methods: HIV incidence rates from 7557 South African women enrolled in five community-based HIV prevention trials (2002-2012) were mapped using participant household global positioning system (GPS) coordinates. Age and period standardized HIV incidence rates were calculated for 43 recruitment clusters across greater Durban. Bayesian conditional autoregressive areal spatial regression (CAR) was used to identify significant patterns and clustering of new HIV infections in recruitment communities.

Results: The total person-time in the cohort was 9093.93 years and 613 seroconversions were observed. The overall crude HIV incidence rate across all communities was 6·74 per 100PY (95% CI: 6·22-7·30). 95% of the clusters had HIV incidence rates greater than 3 per 100PY. The CAR analysis identified six communities with significantly high HIV incidence. Estimated relative risks for these clusters ranged from 1.34 to 1.70. Consistent with these results, age standardized HIV incidence rates were also highest in these clusters and estimated to be 10 or more per 100 PY. Compared to women 35+ years old younger women were more likely to reside in the highest incidence areas (aOR: 1·51, 95% CI: 1·06-2·15; aOR: 1.59, 95% CI: 1·19-2·14 and aOR: 1·62, 95% CI: 1·2-2·18 for < 20, 20-24, 25-29 years old respectively). Partnership factors (2+ sex partners and being unmarried/not cohabiting) were also more common in the highest incidence clusters (aOR 1.48, 95% CI: 1.25-1.75 and aOR 1.54, 95% CI: 1.28-1.84 respectively).

Conclusion: Fine geospatial analysis showed a continuous, unrelenting, hyper HIV epidemic in most of the greater Durban region with six communities characterised by particularly high levels of HIV incidence. The results motivate for comprehensive community-based HIV prevention approaches including expanded access to PrEP. In addition, a higher concentration of HIV related services is required in the highest risk communities to effectively reach the most vulnerable populations.
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http://dx.doi.org/10.1186/s12879-019-4080-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6555962PMC
June 2019

Augmentation of HIV-specific T cell function by immediate treatment of hyperacute HIV-1 infection.

Sci Transl Med 2019 05;11(493)

Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA.

Sustained viremia after acute HIV infection is associated with profound CD4 T cell loss and exhaustion of HIV-specific CD8 T cell responses. To determine the impact of combination antiretroviral therapy (cART) on these processes, we examined the evolution of immune responses in acutely infected individuals initiating treatment before peak viremia. Immediate treatment of Fiebig stages I and II infection led to a rapid decline in viral load and diminished magnitude of HIV-specific (tetramer) CD8 T cell responses compared to untreated donors. There was a strong positive correlation between cumulative viral antigen exposure before full cART-induced suppression and immune responses measured by MHC class I tetramers, IFN-γ ELISPOT, and CD8 T cell activation. HIV-specific CD8 T responses of early treated individuals were characterized by increased CD127 and BCL-2 expression, greater in vitro IFN-γ secretion, and enhanced differentiation into effector memory (T) cells. Transcriptional analysis of tetramer CD8 T cells from treated persons revealed reduced expression of genes associated with activation and apoptosis, with concurrent up-regulation of prosurvival genes including , , and Early treatment also resulted in robust HIV-specific CD4 T cell responses compared to untreated HIV-infected individuals. Our data show that limiting acute viremia results in enhanced functionality of HIV-specific CD4 and CD8 T cells, preserving key antiviral properties of these cells.
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http://dx.doi.org/10.1126/scitranslmed.aau0528DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901350PMC
May 2019

Population-level impact of information sources on HIV testing uptake in South Africa: gender and age disparities.

Int J STD AIDS 2019 07 9;30(8):756-764. Epub 2019 May 9.

2 Biostatistics Unit, South African Medical Research Council, Durban, South Africa.

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http://dx.doi.org/10.1177/0956462419840859DOI Listing
July 2019

Nef-mediated inhibition of NFAT following TCR stimulation differs between HIV-1 subtypes.

Virology 2019 05 21;531:192-202. Epub 2019 Feb 21.

HIV Pathogenesis Programme, University of KwaZulu-Natal, Durban 4001, South Africa. Electronic address:

Functional characterisation of different HIV-1 subtypes may improve understanding of viral pathogenesis and spread. Here, we evaluated the ability of 345 unique HIV-1 Nef clones representing subtypes A, B, C and D to inhibit NFAT signalling following TCR stimulation. The contribution of this Nef function to disease progression was also assessed in 211 additional Nef clones isolated from unique subtype C infected individuals in early or chronic infection. On average, subtype A and C Nef clones exhibited significantly lower ability to inhibit TCR-mediated NFAT signalling compared to subtype B and D Nef clones. While this observation corroborates accumulating evidence supporting relative attenuation of subtypes A and C that may paradoxically contribute to their increased global prevalence and spread, no significant correlations between Nef-mediated NFAT inhibition activity and clinical markers of HIV-1 infection were observed, indicating that the relationship between Nef function and pathogenesis is complex.
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http://dx.doi.org/10.1016/j.virol.2019.02.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6526282PMC
May 2019

Correlates of Sexually Transmitted Infections Among South African Women Using Individual- and Community-Level Factors: Results from Generalized Additive Mixed Models.

Arch Sex Behav 2020 08 14;49(6):1875-1886. Epub 2019 Feb 14.

Biostatistics Unit, South African Medical Research Council, Durban, Kwazulu-Natal, South Africa.

South Africa has the highest burden of human immunodeficiency virus (HIV) infections in the world. There is also growing evidence that an individual's risk of contracting HIV is increased by the presence of other sexually transmitted infections (STIs). The primary objective of this study was to examine the association between the prevalence of STIs in a cohort of South African women who enrolled in HIV prevention trials (2002-2012). The current study linked the individual factors with the community-level characteristics using geo-referencing. These multi-level data were analyzed in generalized additive mixed models settings. In the multivariate logistic regression model, younger age (odds ratio [OR] 4.30, 95% CI 3.20, 5.77 and OR 2.72, 95% CI 2.02, 3.66 for age < 25 and 25-29, respectively); being single/not cohabiting (OR 4.57, 95% CI 3.18, 6.53), two + sex partners (OR 1.46, 95% CI 1.18,1.80); parity < 2 (OR 2.04, 95% CI 1.53, 2.72), parity = 2 (OR 1.85, 95% CI 1.37, 2.48), and using injectables (contraceptive) (OR 1.53, 95% CI 1.13, 2.06) were all significantly associated with increased prevalence of STIs. Women who resided in the communities with high proportions of female headed-households were also significantly at higher risk for STIs (OR 1.20, p = .0025). Because these factors may reflect characteristics of the larger groups who share similar cultural norms and social environments, they can provide considerable insight into the spread of STIs. Prevention strategies based on individual and community-level drivers of STIs are likely to be the most effective means of targeting and reaching those at greatest risk of infection. This strategy has the potential to play a significant role in the epidemic's trajectory.
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http://dx.doi.org/10.1007/s10508-018-1315-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6944771PMC
August 2020
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