Browsing by Author "Bekker, Linda-Gail"

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    A novel cash-plus intervention to safeguard sexual reproductive health and HIV vulnerabilities in young women in Cape Town, South Africa
    (2023) Naledi Tracey, Noncayana; Bekker, Linda-Gail; London, Leslie
    Background Cash plus interventions augment cash transfers with other empowering interventions to influence behaviours. This research assesses the Women of Worth (WoW) program and evaluates the effectiveness of a cash transfer (CT) of ZAR300 ($22USD22) conditional on attending 12-session customised empowerment interventions to improve SRH/HIV outcomes in young women (19-24yrs) in Cape Town, South Africa. Methods A multiphase, mixed-methods, experimental study targeting 10 000 Participants in two subdistricts was conducted. Participants were randomised 1:1 to receive the interventions with CT ("cash + care" or C+C) or without CT (“Care”). Phase 1a piloted the interventions, Phase 1b implemented an adapted intervention, and Phase 2 was an open label C+C only scale up demonstration phase. Logistic regression models were fitted with subject-specific random mixed effects, to estimate changes in self-reported HIV, behavioural and structural SRH risks from baseline to (a) end of WoW and (b) follow up (6-30months post-exposure) irrespective of WoW completion. Mixed research methods were used to optimise engagement, evaluate implementation fidelity and determine the pathways of effectiveness for the interventions. Results The Women of Worth empowerment programme was implemented with adequate fidelity however adaptative research methods were essential for ensuring a sustained programme. 8765 (87,7%) of the 9995 WoW initiators were evaluated with 904 (10,3%); 4212 (48,1%) and 3649 (41,6%) women in Phases 1a, 1b and 2 respectively. In Phase 1a & 1b, participants in the “C+C” group were 60 times (OR 60.37; 95%CI: 17.32; 210.50.p
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    Acceptability, safety, and patterns of use of oral pre-exposure prophylaxis to prevent HIV in healthy, South African adolescents
    (2022) Gill, Katherine; Bekker, Linda-Gail
    Background: HIV incidence amongst adolescents in Southern Africa remains extremely high. The importance of adolescent HIV prevention strategies in tackling the epidemic worldwide is increasingly recognised with a global target from UNICEF to reduce new adolescent HIV infections by 75% by 2020. Adolescent vulnerability to HIV infection is a result of a complex interplay between structural, economic, socio-cultural, and biological factors during a phase when behaviours associated with HIV acquisition and sexual and reproductive health-seeking are initiated. The vulnerability of young people to HIV is particularly manifest in South Africa, where young women aged 15-24 accounted for almost 40% of new HIV infections in 2017. PreExposure Prophylaxis (PrEP) has been demonstrated to be effective for preventing HIV infection in adults but there is little data on its implementation among young people. Given the HIV incidence rates amongst adolescents in Southern Africa, oral PrEP for this group is likely to have an impact on population-level HIV incidence. We designed an open-label demonstration study known as Pluspills, for adolescents aged 15-19 years in South Africa to understand the safety, feasibility, and patterns of use of oral pre-exposure prophylaxis (PrEP) as part of a broad package of interventions, to prevent HIV. Methods: Pluspills was conducted in two distinct peri-urban settings in Johannesburg and Cape Town. The aim was to study the safety and acceptability of oral PrEP (tenofovir disoproxil fumarate/Emtricitabine) in two adolescent populations in South Africa. HIV-negative participants between 15-19 years old participated in an open-label oral PrEP study over 52 weeks. Participants took daily PrEP for the first 12 weeks and were then given the choice to opt-in or opt-out of PrEP use at three-monthly intervals. Serial plasma and DBS tenofovir concentrations were measured at every PrEP refill visit, and results were discussed with participants during adherence counselling sessions. Testing for sexually transmitted infections (STI's) was conducted at baseline, twelve and forty-eight weeks. Findings: Overall 148 participants were enrolled (median age 18 years; 67% female) and initiated PrEP. STI prevalence at the study start was high at 41% (60/148) and remained high throughout the study. The decision to stop using PrEP was made by 26 (18%) participants at 6 the 12-week visit. Cumulative PrEP opt-out at weeks 24 and 36 comprised 41% (60/148) and 43% (63/148) of the total cohort respectively. PrEP was relatively well tolerated with few reported adverse events. Tenofovir diphosphate (TFV-DP) levels as measured in dried blood spot samples were detectable (>16fmol/punch) in 92% (108/118)) of participants who reported PrEP use at week 12, 74% at week 24 (74/100), and 58% (22/37) by the end of the study. One HIV seroconversion occurred during the study (0.76/100 person-years) in a 19-yearold female participant who had chosen to stop taking PrEP, 24 weeks before diagnosis. Interpretation: In this small cohort of South African adolescents at risk of HIV acquisition, PrEP was safe and well-tolerated in those who continued to use it. PrEP use decreased throughout the study as visit frequency declined. The incidence of sexually transmitted infections remained high, despite low HIV incidence. The study confirms that this population needs access to PrEP with particular attention to tailored adherence support. Young people would also possibly benefit from the option for more frequent and flexible visit schedules.
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    Antiretroviral therapy in a community clinic - early lessons from a pilot project
    (Health and Medical Publishing Group, 2003) Bekker, Linda-Gail; Orrell, Catherine; Reader, Larissa; Matoti, Larissa; Cohen, Karen; Martell, Rob; Abdullah, Fareed; Wood, Robin
    Objectives. To report on operational and clinical problems encountered during the first 6 months of a community-based antiretroviral therapy (ART) programme. Methods. ART was implemented in a primary care setting utilising an easily replicable service-delivery model based on a medical officer and nurse. Therapeutic counsellors, themselves HIV-infected, provided counselling and adherence support. Drug and monitoring costs were charitably funded and provincial health authorities supplied the medical infrastructure. The HIV Research Unit, University of Cape Town, supplied training and additional clinical support. Local HIV primary care clinics provided patient referrals. Standardised ART regimens were used with strict entry criteria (AIDS or CD4 count < 200 cells/µl). Results. Demand for the service was high. Referred patients had advanced disease (AIDS 57%, median CD4 count 96/µl) and high pre-treatment mortality (83/100 person-years). Mycobacterial disease was a major contributor to this mortality (40%). Scheduled clinic visit hours were six times higher during recruitment than maintenance. Attributable costs were: drugs 61%, staff 27%, viral load and CD4 cell counts 10% and safety monitoring 2%. Viral load after 16 weeks of therapy was < 400 copies/ml in the first 16 patients. Conclusions. ART can be successfully implemented within a primary care setting. Drug purchases and staff salaries drive programme costing. The service model is capable of managing 250 - 300 patients on chronic ART, but staffing needs to be increased during recruitment. Attention must be given to the diagnosis of tuberculosis during screening and early ART. Incorporating therapeutic counsellors into the programme increased community involvement and utilised a valuable and previously untapped resource.
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    Antiretroviral treatment cohort analysis using time-updated CD4 counts: assessment of bias with different analytic methods
    (Public Library of Science, 2011) Kranzer, Katharina; Lewis, James J; White, Richard G; Glynn, Judith R; Lawn, Stephen D; Middelkoop, Keren; Bekker, Linda-Gail; Wood, Robin
    BACKGROUND: Survival analysis using time-updated CD4+ counts during antiretroviral therapy is frequently employed to determine risk of clinical events. The time-point when the CD4+ count is assumed to change potentially biases effect estimates but methods used to estimate this are infrequently reported. METHODS: This study examined the effect of three different estimation methods: assuming i) a constant CD4+ count from date of measurement until the date of next measurement, ii) a constant CD4+ count from the midpoint of the preceding interval until the midpoint of the subsequent interval and iii) a linear interpolation between consecutive CD4+ measurements to provide additional midpoint measurements. Person-time, tuberculosis rates and hazard ratios by CD4+ stratum were compared using all available CD4+ counts (measurement frequency 1-3 months) and 6 monthly measurements from a clinical cohort. Simulated data were used to compare the extent of bias introduced by these methods. RESULTS: The midpoint method gave the closest fit to person-time spent with low CD4+ counts and for hazard ratios for outcomes both in the clinical dataset and the simulated data. CONCLUSION: The midpoint method presents a simple option to reduce bias in time-updated CD4+ analysis, particularly at low CD4 cell counts and rapidly increasing counts after ART initiation.
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    Are the effects of isoniaid preventive therapy and highly active antiretroviral therapy additive in preventing HIV-associated tuberculosis
    (2009) Wood, Robin; Lawn, Stephen D; Bekker, Linda-Gail
    Golub et al. [1] recently reported a retrospective analysis of rates of incident tuberculosis (TB) in a large observational cohort of 2778 patients accessing HIV care in rural and urban South Africa. The TB incidence rate was highest [7.1/100 person-years; 95% confidence interval (CI)¼ 6.2–8.2] during the period of care when patients did not receive isoniazid preventive therapy (IPT) or highly active antiretroviral therapy (HAART). The rates were lower during person-time that accrued throughout follow-up after initiation of IPT (5.2/100 person-years; 95% CI¼ 3.4–7.8) and throughout follow-up on HAART alone (4.6/100 person-years, 95% CI¼ 3.4– 6.2). The rate was lower still (1.1/100 person-years 95% CI¼ 0.2–7.6) during person-time accrued during sequential IPT and HAART (IPTþ HAART). The authors concluded that TB risk was significantly reduced by IPT in HAART-treated adults. It was further concluded that 'the dramatic reduction in TB risk' demonstrated in this study together with supportive data from a similarly analysed study from Brazil [2] indicates that widespread use 1444 AIDS 2009, Vol 23 No 11 Fig. 1. T2-weighted flair image demonstrating enhancing lesion in the right precentral gyrus. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. of IPT should be implemented in conjunction with the roll-out of HAART.
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    Are the effects of isoniaid preventive therapy and highly active antiretroviral therapy additive in preventing HIV-associated tuberculosis
    (2009) Wood, Robin; Lawn, Stephen D; Bekker, Linda-Gail
    Golub et al. [1] recently reported a retrospective analysis of rates of incident tuberculosis (TB) in a large observational cohort of 2778 patients accessing HIV care in rural and urban South Africa. The TB incidence rate was highest [7.1/100 person-years; 95% confidence interval (CI)¼ 6.2–8.2] during the period of care when patients did not receive isoniazid preventive therapy (IPT) or highly active antiretroviral therapy (HAART). The rates were lower during person-time that accrued throughout follow-up after initiation of IPT (5.2/100 person-years; 95% CI¼ 3.4–7.8) and throughout follow-up on HAART alone (4.6/100 person-years, 95% CI¼ 3.4– 6.2). The rate was lower still (1.1/100 person-years 95% CI¼ 0.2–7.6) during person-time accrued during sequential IPT and HAART (IPTþ HAART). The authors concluded that TB risk was significantly reduced by IPT in HAART-treated adults. It was further concluded that ‘the dramatic reduction in TB risk’ demonstrated in this study together with supportive data from a similarly analysed study from Brazil [2] indicates that widespread use 1444 AIDS 2009, Vol 23 No 11 Fig. 1. T2-weighted flair image demonstrating enhancing lesion in the right precentral gyrus. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. of IPT should be implemented in conjunction with the roll-out of HAART.
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    Behavioural economics: The missing ingredient that makes sexual health services responsive and acceptable to young South Africans
    (2019) Smith, Philip John; Bekker, Linda-Gail
    Introduction: South African adolescents and young adults (AYA) remain at high risk of HIV infection despite reductions in HIV incidence in older adult populations. This is, in part, attributable to suboptimal levels of health-seeking behaviour. Behavioural economics provides insight into why conventional efforts to generate health-seeking behaviour have struggled to curb HIV infection in South African AYA and in designing more desirable, scalable interventions to better serve youth and promote sexual health. Methods: Focus group discussions gathered information on sexual health service wants from AYA in high HIV disease burden, limited resource communities. Based on this data, three AYA friendly services were designed, including a diagnostic screen (HIV self-testing, HIVST), a prevention intervention (male medical circumcision), and a service platform (mobile clinic). All three studies evaluated acceptability. The circumcision and the mobile clinic studies described service uptake. The mobile clinic study compared uptake of services with four conventional clinics in the same community. Results: Participants recommended that services be easily accessible, friendly services, age appropriate, tailored information, and improved relationships with healthcare workers. Participants in the mobile clinic study (n=304) rated mobile services' acceptability highly (median = 4,6 out of 5), attracting more males proportionally than conventional clinics. The HIVST study (n=224) found high fidelity (96%), usability (median 3.9 out of 5), and acceptability ratings (median 4.3 out of 5). The circumcision study conducted in culturally distinct locations (Cape Town n=50; Soweto n=50) identified that Soweto males in this age range (14-17 years) were 19 times more likely (n=13) to have been circumcised than those in Cape Town (n=1) (HR 18.9, 95% CI 2.37-150.71, p= 0.006) over study duration. Conclusions: Given the high ratings for acceptability, AYA tailored services should be investigated as part of a multipronged approach to diagnostic, prevention, and health system options. Besides development and age considerations, the contrast between MMC uptake in Cape Town versus Soweto indicate that cultural beliefs and tradition may also strongly influence specific key interventions. Overall, using a behavioural economics framework to design and implement AYA recommendations received a positive reception. These findings support recommendations to provide differentiated care to AYA.
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    Broadly neutralizing antibody responses in a large longitudinal sub-Saharan HIV primary infection cohort
    (Public Library of Science, 2016) Landais, Elise; Huang, Xiayu; Havenar-Daughton, Colin; Murrell, Ben; Price, Matt A; Wickramasinghe, Lalinda; Ramos, Alejandra; Bian, Charoan B; Simek, Melissa; Allen, Susan; Karita, Etienne; Kilembe, William; Lakhi, Shabir; Inambao, Mubiana; Kamali, Anatoli; Sanders, Eduard J; Anzala, Omu; Edward, Vinodh; Bekker, Linda-Gail; Tang, Jianming; Gilmour, Jill; Kosakovsky-Pond, Sergei L; Phung, Pham; Wrin, Terri; Crotty, Shane; Godzik, Adam; Poignard, Pascal
    Author Summary Understanding how HIV-1-broadly neutralizing antibodies (bnAbs) develop during natural infection is essential to the design of an efficient HIV vaccine. We studied kinetics and correlates of neutralization breadth in a large sub-Saharan African longitudinal cohort of 439 participants with primary HIV-1 infection. Broadly nAb responses developed in 15% of individuals, on average three years after infection. Broad neutralization was associated with high viral load, low CD4+ T cell counts, virus subtype C infection and HLA*A3(-) genotype. A correlation with high overall plasma IgG levels and anti-Env binding titers was also found. Specificity mapping of the bnAb responses showed that glycan-dependent epitopes, in particular the N332 region, were most commonly targeted, in contrast to other bnAb epitopes, suggesting that the HIV Env N332-glycan epitope region may be a favorable target for vaccine design.
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    Burden of new and recurrent tuberculosis in a major South African city stratified by age and HIV-status
    (Public Library of Science, 2011) Wood, Robin; Lawn, Stephen D; Caldwell, Judy; Kaplan, Richard; Middelkoop, Keren; Bekker, Linda-Gail
    Aim: To describe the burden of tuberculosis (TB) in Cape Town by calculating TB incidence rates stratified by age and HIV-status, assessing the contribution of retreatment disease and estimating the cumulative lifetime TB risk in HIV-negative individuals. METHODS: Details of TB cases were abstracted from the 2009 electronic TB register. Population denominators were estimated from census data and actuarial estimates of HIV prevalence, allowing calculation of age-specific and HIV-stratified TB notification rates. RESULTS: The 2009 mid-year population was 3,443,010 (3,241,508 HIV-negative and 201,502 HIV-positive individuals). There were 29,478 newly notified TB cases of which 56% were laboratory confirmed. HIV status was recorded for 87% of cases and of those with known HIV-status 49% were HIV-negative and 51% were positive. Discrete peaks in the incidence of non-HIV-associated TB occurred at three ages: 511/100,000 at 0-4 years of age, 553/100,000 at 20-24 years and 628/100,000 at 45-49 years with 1.5%, 19% and 45% being due to retreatment TB, respectively. Only 15.5% of recurrent cases had a history of TB treatment failure or default. The cumulative lifetime risks in the HIV-negative population of all new TB episodes and new smear-positive TB episodes were 24% and 12%, respectively; the lifetime risk of retreatment disease was 9%. The HIV-positive notification rate was 6,567/100,000 (HIV-associated TB rate ratio = 17). Although retreatment cases comprised 30% of the HIV-associated TB burden, 88% of these patients had no history of prior treatment failure or default. CONCLUSIONS: The annual burden of TB in this city is huge. TB in the HIV-negative population contributed almost half of the overall disease burden and cumulative lifetime risks were similar to those reported in the pre-chemotherapy era. Retreatment TB contributed significantly to both HIV-associated and non-HIV-associated TB but infrequently followed prior inadequate treatment. This likely reflects ongoing TB transmission to both HIV-negative and positive individuals.
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    CD4 cell count recovery among HIV-infected patients with very advanced immunodeficiency commencing antiretroviral treatment in sub-Saharan Africa
    (BioMed Central Ltd, 2006) Lawn, Stephen; Myer, Landon; Bekker, Linda-Gail; Wood, Robin
    BACKGROUND:Patients accessing antiretroviral treatment (ART) programmes in sub-Saharan Africa frequently have very advanced immunodeficiency. Previous data suggest that such patients may have diminished capacity for CD4 cell count recovery. METHODS: Rates of CD4 cell increase were determined over 48 weeks among ART-naive individuals (n = 596) commencing ART in a South African community-based ART programme. RESULTS: The CD4 cell count increased from a median of 97 cells/mul at baseline to 261 cells/mul at 48 weeks and the proportion of patients with a CD4 cell count <100 cells/mul decreased from 51% at baseline to just 4% at 48 weeks. A rapid first phase of recovery (0-16 weeks, median rate = 25.5 cells/mul/month) was followed by a slower second phase (16-48 weeks, median rate = 7.7 cells/mul/month). Compared to patients with higher baseline counts, multivariate analysis showed that those with baseline CD4 counts <50 cells/mul had similar rates of phase 1 CD4 cell recovery (P = 0.42), greater rates of phase 2 recovery (P = 0.007) and a lower risk of immunological non-response (P = 0.016). Among those that achieved a CD4 cell count >500 cells/mul at 48 weeks, 19% had baseline CD4 cell counts <50 cells/mul. However, the proportion of these patients that attained a CD4 count 200 cells/mul at 48 weeks was lower than those with higher baseline CD4 cell counts. CONCLUSION: Patients in this cohort with baseline CD4 cell counts <50 cells/mul have equivalent or greater capacity for immunological recovery during 48 weeks of ART compared to those with higher baseline CD4 cell counts. However, their CD4 counts remain <200 cells/mul for a longer period, potentially increasing their risk of morbidity and mortality in the first year of ART.
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    Cervicovaginal Human Papillomavirus Genomes, Microbiota Composition and Cytokine Concentrations in South African Adolescents
    (Multidisciplinary Digital Publishing Institute, 2023-03-15) Happel, Anna-Ursula; Balle, Christina; Havyarimana, Enock; Brown, Bryan; Maust, Brandon S.; Feng, Colin; Yi, Byung H.; Gill, Katherine; Bekker, Linda-Gail; Passmore, Jo-Ann S.; Jaspan, Heather B.; Varsani, Arvind
    The interaction between cervicovaginal virome, bacteriome and genital inflammation has not been extensively investigated. We assessed the vaginal DNA virome from 33 South African adolescents (15–19 years old) using shotgun DNA sequencing of purified virions. We present analyses of eukaryote-infecting DNA viruses, with a focus on human papillomavirus (HPV) genomes and relate these to the vaginal bacterial microbiota (assessed by 16S rRNA gene sequencing) and cytokines (assessed by Luminex). The DNA virome included single-stranded (Anelloviridae, Genomoviridae) and double-stranded DNA viruses (Adenoviridae, Alloherpesviridae, Herpesviridae, Marseilleviridae, Mimiviridae, Polyomaviridae, Poxviridae). We identified 110 unique, complete HPV genomes within two genera (Alphapapillomavirus and Gammapapillomavirus) representing 40 HPV types and 12 species. Of the 40 HPV types identified, 35 showed positive co-infection patterns with at least one other type, mainly HPV-16. HPV-35, a high-risk genotype currently not targeted by available vaccines, was the most prevalent HPV type identified in this cohort. Bacterial taxa commonly associated with bacterial vaginosis also correlated with the presence of HPV. Bacterial vaginosis, rather than HPV, was associated with increased genital inflammation. This study lays the foundation for future work characterizing the vaginal virome and its role in women’s health.
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    Childhood tuberculosis infection and disease: A spatial and temporal transmission analysis in a South African township
    (2009) Middelkoop, Keren; Bekker, Linda-Gail; Morrow, Carl; Zwane, Eugene; Wood, Robin
    Background. Tuberculosis (TB) remains a leading cause of South African mortality and morbidity. While adult TB arises from both recent and prior infection, childhood TB results from recent infection and reflects ongoing transmission occurring despite current TB control strategies. Setting. A South African community with high rates of TB and HIV disease. Outcomes. A Geographic Information System was used to spatially and temporally define the relationships between TB exposure, infection and disease in children <15 years of age, with exposure to adult HIV-positive and HIV-negative TB disease on residential plots between 1997 and 2007. Results. During the study period the annual adult TB notification rate increased from 629 to 2106/100,000 and <15yrs TB notification rate ranged between 664/100,000 and 1044/100,000. The mean exposure to adult TB for uninfected children, TB-infected, TB cases was 5.1%, 5.4% and 33% per annum and the mean number of adult smear-positive cases per exposed child was 1.0, 1.6 and 1.9 respectively. Acquisition of TB infection was not associated with HIV status of adult exposure TB case and 36% of child TB cases were diagnosed prior to the temporally closest adult case on their plot. Conclusions. Childhood infection and disease were quantitatively linked to infectious adult TB prevalence in an immediate social network. Childhood infection should be monitored in high burden settings as a marker of ongoing TB transmission. Improved knowledge of township childhood and adult social networks may also facilitate targeted active case finding, which may provide an adjunct to presently failing TB control strategies.
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    Community health care workers in South Africa are at increased risk for tuberculosis
    (2010) Kranzer, Kathar; Bekker, Linda-Gail; van Schaik, N; Thebus, L; Dawson, M; Caldwell, J; Hausler, H; Grant, R; Wood, R
    Many sub-Saharan African countries face a severe shortage of qualified HCWs as a result of the dual HIV/TB epidemic, which has triggered task shifting to a range of lay community health care workers (CHWs) – for example, home-based care workers, lay counsellors and adherence supporters, for both TB and highly active antiretroviral therapy (HAART). CHWs may experience a considerable occupational TB risk; however, their risk of TB disease and HIV prevalence has never been documented.
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    Continued follow-up of Phambili Phase 2b randomized HIV-1 vaccine trial participants supports increased HIV-1 acquisition among vaccinated men
    (Public Library of Science, 2015) Moodie, Zoe; Metch, Barbara; Bekker, Linda-Gail; Churchyard, Gavin; Nchabeleng, Maphoshane; Mlisana, Koleka; Laher, Fatima; Roux, Surita; Mngadi, Kathryn; Innes, Craig
    BACKGROUND: The Phase 2b double-blinded, randomized Phambili/HVTN 503 trial evaluated safety and efficacy of the MRK Ad5 gag / pol / nef subtype B HIV-1 preventive vaccine vs placebo in sexually active HIV-1 seronegative participants in South Africa. Enrollment and vaccinations stopped and participants were unblinded but continued follow-up when the Step study evaluating the same vaccine in the Americas, Caribbean, and Australia was unblinded for non-efficacy. Final Phambili analyses found more HIV-1 infections amongst vaccine than placebo recipients, impelling the HVTN 503-S recall study. METHODS: HVTN 503-S sought to enroll all 695 HIV-1 uninfected Phambili participants, provide HIV testing, risk reduction counseling, physical examination, risk behavior assessment and treatment assignment recall. After adding HVTN 503-S data, HIV-1 infection hazard ratios (HR vaccine vs. placebo) were estimated by Cox models. RESULTS: Of the 695 eligible, 465 (67%) enrolled with 230 from the vaccine group and 235 from the placebo group. 38% of the 184 Phambili dropouts were enrolled. Enrollment did not differ by treatment group, gender, or baseline HSV-2. With the additional 1286 person years of 503-S follow-up, the estimated HR over Phambili and HVTN 503-S follow-up was 1.52 (95% CI 1.08-2.15, p = 0.02, 82 vaccine/54 placebo infections). The HR was significant for men (HR = 2.75, 95% CI 1.49, 5.06, p = 0.001) but not for women (HR = 1.12, 95% CI 0.73, 1.72, p = 0.62). CONCLUSION: The additional follow-up from HVTN 503-S supported the Phambili finding of increased HIV-1 acquisition among vaccinated men and strengthened the evidence of lack of vaccine effect among women. Trial Registration clinicaltrials.gov NCT00413725 SA National Health Research Database DOH-27-0207-1539
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    Cost-effectiveness of highly active antiretroviral therapy in South Africa
    (Public Library of Science, 2005) Badri, Motasim; Maartens, Gary; Mandalia, Sundhiya; Bekker, Linda-Gail; Penrod, John R; Platt, Robert W; Wood, Robin; Beck, Eduard J
    Healthcare costs for HIV-infected South African adults on HAART compared with costs for HIV-infected controls not on HAART. Authors conclude HAART is cost effective.
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    Creating an African HIV clinical research and prevention trials network: HIV prevalence, incidence and transmission
    (Public Library of Science, 2015) Kamali, Anatoli; Price, Matt A; Lakhi, Shabir; Karita, Etienne; Inambao, Mubiana; Sanders, Eduard J; Anzala, Omu; Latka, Mary H; Bekker, Linda-Gail; Kaleebu, Pontiano
    HIV epidemiology informs prevention trial design and program planning. Nine clinical research centers (CRC) in sub-Saharan Africa conducted HIV observational epidemiology studies in populations at risk for HIV infection as part of an HIV prevention and vaccine trial network. Annual HIV incidence ranged from below 2% to above 10% and varied by CRC and risk group, with rates above 5% observed in Zambian men in an HIV-discordant relationship, Ugandan men from Lake Victoria fishing communities, men who have sex with men, and several cohorts of women. HIV incidence tended to fall after the first three months in the study and over calendar time. Among suspected transmission pairs, 28% of HIV infections were not from the reported partner. Volunteers with high incidence were successfully identified and enrolled into large scale cohort studies. Over a quarter of new cases in couples acquired infection from persons other than the suspected transmitting partner.
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    Decreasing household contribution to TB transmission with age: a retrospective geographic analysis of young people in a South African township
    (BioMed Central Ltd, 2014) Middelkoop, Keren; Bekker, Linda-Gail; Morrow, Carl; Lee, Namee; Wood, Robin
    BACKGROUND: Tuberculosis (TB) transmission rates are exceptionally high in endemic TB settings. Adolescence represents a period of increasing TB infection and disease but little is known as to where adolescents acquire TB infection. We explored the relationship between residential exposure to adult TB cases and infection in children and adolescents in a South African community with high burdens of TB and HIV. METHODS: TB infection data were obtained from community, school-based tuberculin skin test (TST) surveys performed in 2006, 2007 and 2009. A subset of 2007 participants received a repeat TST in 2009, among which incident TB infections were identified. Using residential address, all adult TB cases notified by the community clinic between 1996 and 2009 were cross-referenced with childhood and adolescent TST results. Demographic and clinic data including HIV status were abstracted for TB cases. Multivariate logistic regression models examined the association of adult TB exposure with childhood and adolescent prevalent and incident TB infection. RESULTS: Of 1,100 children and adolescents included in the prevalent TB infection analysis, 480 (44%) were TST positive and 651 (59%) were exposed to an adult TB case on their residential plot. Prevalent TB infection in children aged 5-9 and 10-14 years was positively associated with residential exposure to an adult TB case (odds ratio [OR]:2.0; 95% confidence interval [CI]: 1.1-3.6 and OR:1.5; 95% CI: 1.0-2.3 respectively), but no association was found in adolescents [greater than or equal to]15years (OR:1.4; 95% CI: 0.9-2.0). HIV status of adult TB cases was not associated with TB infection (p=0.62). Of 67 previously TST negative children, 16 (24%) converted to a positive TST in 2009. These incident infections were not associated with residential exposure to an adult TB case (OR: 1.9; 95% CI: 0.5-7.3). CONCLUSIONS: TB infection among young children was strongly associated with residential exposure to an adult TB case, but prevalent and incident TB infection in adolescents was not associated with residential exposure. The HIV-status of adult TB cases was not a risk factor for transmission. The high rates of TB infection and disease among adolescents underscore the importance of identifying where infection occurs in this age group.
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    Do we need a national antiretroviral treatment register?
    (Health and Medical Publishing Group, 2003) Bekker, Linda-Gail; Wood, Robin
    Combination antiretroviral therapy (ART) has greatly improved the prognosis of HIV-infected individuals in affluent countries, resulting in a marked drop in AIDS-related mortality. 1-3 ART programmes have also been successfully initiated in less well-resourced health systems. Brazil, a middle-income developing country, has incorporated ART into its public health service4 and a successful ART programme has been implemented in rural Haiti, the poorest country in the Western hemisphere.5
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    Epidemiology of HIV-1 subtypes among men who have sex with men in Cape Town, South Africa
    (2013) Middelkoop, Keren; Myer, Landon; Bekker, Linda-Gail
    There are few data describing the HIV epidemic among men who have sex with men (MSM) in South Africa, and thus little information is available to inform appropriate public health response strategies for this high-risk group. One such existing knowledge gap is an understanding of HIV transmission patterns between different MSM communities and between MSM and the heterosexual population. Studies in the early 1990s identified two independent HIV-1 epidemics in Cape Town: a predominantly subtype B epidemic among white MSM and the mainly subtype C epidemic among the predominantly black heterosexual epidemic. While the heterosexual epidemic remains primarily due to subtype C virus, few recent HIV-1 subtype data are available for MSM in South Africa. This study examined circulating HIV-1 subtypes among MSM in Cape Town.
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    Feasibility, yield, and cost of active tuberculosis case finding linked to a mobile HIV service in Cape Town, South Africa: a cross-sectional study
    (Public Library of Science, 2012) Kranzer, Katharina; Lawn, Stephen D; Meyer-Rath, Gesine; Vassall, Anna; Raditlhalo, Eudoxia; Govindasamy, Darshini; Van Schaik, Nienke; Wood, Robin; Bekker, Linda-Gail
    Katharina Kranzer and colleagues investigate the operational characteristics of an active tuberculosis case-finding service linked to a mobile HIV testing unit that operates in underserviced areas in Cape Town, South Africa.