Establishing a Cohort at High Risk of HIV Infection in South Africa: Challenges and Experiences of the CAPRISA 002 Acute Infection Study

Abstract

ObjectivesTo describe the baseline demographic data, clinical characteristics and HIV-incidence rates of a cohort at high risk for HIV infection in South Africa as well as the challenges experienced in establishing and maintaining the cohort.Methodology/Principle FindingsBetween August 2004 and May 2005 a cohort of HIV-uninfected women was established for the CAPRISA 002 Acute Infection Study, a natural history study of HIV-1 subtype C infection. Volunteers were identified through peer-outreach. The cohort was followed monthly to determine HIV infection rates and clinical presentation of early HIV infection. Risk reduction counselling and male and female condoms were provided. After screening 775 individuals, a cohort of 245 uninfected high-risk women was established. HIV-prevalence at screening was 59.6% (95% CI: 55.9% to 62.8%) posing a challenge in accruing HIV-uninfected women. The majority of women (78.8%) were self-identified as sex-workers with a median of 2 clients per day. Most women (95%) reported more than one casual sexual partner in the previous 3 months (excluding clients) and 58.8% reported condom use in their last sexual encounter. Based on laboratory testing, 62.0% had a sexually transmitted infection at baseline. During 390 person-years of follow-up, 28 infections occurred yielding seroincidence rate of 7.2 (95% CI: 4.5 to 9.8) per 100 person-years. Despite the high mobility of this sex worker cohort retention rate after 2 years was 86.1%. High co-morbidity created challenges for ancillary care provision, both in terms of human and financial resources.Conclusions/SignificanceChallenges experienced were high baseline HIV-prevalence, lower than anticipated HIV-incidence and difficulties retaining participants. Despite challenges, we have successfully accrued this cohort of HIV-uninfected women with favourable retention, enabling us to study the natural history of HIV-1 during acute HIV-infection. Our experiences provide lessons for others establishing similar cohorts, which will be key for advancing the vaccine and prevention research agenda in resource-constrained settings.

Human Immunodeficiency Virus-Specific Gamma Interferon Enzyme-Linked Immunospot Assay Responses Targeting Specific Regions of the Proteome during Primary Subtype C Infection Are Poor Predictors of the Course of Viremia and Set Point

“…Overall, there was no significant relationship between the magnitude of IFN-␥ ELISPOT assay responses and the course of viremia, early disease progression, or the set point. Our study examined a subtype C HIV-1 acute-infection cohort recruited in Kwa-Zulu Natal, the province in South Africa worst hit by the HIV-1 epidemic, which we have followed for more than 2 years (38). We hypothesized that Gag-specific T-cell responses established early after infection would be associated with virus control and a low set point based on prior data showing that preferential targeting of Gag regions was associated with low viral loads (28).…”

“…An ongoing longitudinal cohort of acutely HIV-1-infected individuals were enrolled as part of the Centre for AIDS Programme Research in South Africa (CAPRISA) 002 acute-infection study in Durban, South Africa (38). We report on 47 individuals in the cohort.…”

“…The time postinfection was estimated by a prospective RNA-positive/antibody-negative measurement or was taken as the midpoint between the last antibody-negative test and the first antibody-positive enzyme-linked immunosorbent assay. The study cohort wasn described previously (38), when study participants were followed for up to 24 months, and the study is still ongoing; data from events within the first 3 to 12 months are reported here. The University of KwaZulu-Natal, University of Witwatersrand, and University of Cape Town Ethics Committees approved this study, and all the subjects provided written informed consent for participation in the study.…”

Potent and Broad Neutralization of HIV-1 Subtype C by Plasma Antibodies Targeting a Quaternary Epitope Including Residues in the V2 Loop

“…CAP256 was enrolled in the CAPRISA Acute Infection study (42) Both cell lines were cultured in Dulbecco's modified Eagle medium (Gibco BRL Life Technologies) containing 10% heat-inactivated fetal bovine serum and 50 g/ml gentamicin (Sigma). Cell monolayers were disrupted at confluence by treatment with 0.25% trypsin in 1 mM EDTA.…”

Characteristics, sexual behaviour and risk factors of female, male and transgender sex workers in South Africa

“…[3,4,6] In a 2004 -2005 Durban study, 775 women at high risk for HIV infection -78.8% of whom selfidentified as sex workers -were screened, and 59.6% were found to be HIV-positive. [7] More recent estimates are not available. A recent meta-analysis emphasised the considerable risk that HIV poses to FSWs.…”