Objective: To investigate HIV incidence during a trial of two voluntary counselling and testing (VCT) strategies. Counselling may promote beneficial behavioural change, although knowledge of negative status does not appear to contribute further benefit.
Design: The parent cluster-randomized trial demonstrated much greater uptake of VCT when counselling and rapid testing were available on-site (intensive VCT) than through pre-paid vouchers to an external provider (standard VCT). Anonymous HIV tests had been requested from all employees at enrolment and after 2 years intervention.
Methods: The study setting was 22 businesses in Harare, Zimbabwe. Participants were 3146 HIV-negative individuals remaining in employment at the end of intervention, of whom 2966 (94.3%) consented to repeat testing. VCT linked to basic HIV care was provided and the main outcome measures were HIV incidence under each study arm, as a retrospective secondary analysis.
Results: Mean VCT uptake in this cohort was 70.7 and 5.2%, respectively, in the intensive and standard arms. Crude HIV incidence was 1.21 per 100 person-years, with non-significantly higher rates in the intensive VCT arm [mean site incidence 1.37 and 0.95 per 100 person-years, respectively; adjusted rate ratio 1.49 (95% confidence interval 0.79–2.80).
Conclusions: Highly acceptable VCT did not reduce HIV incidence in this predominantly male cohort. HIV incidence was highest in the high uptake VCT arm, lending support to a US trial in which rapid testing appeared to have adverse behavioural consequences in some HIV-negative clients. Careful comparison of outcomes under different counselling and testing strategies is needed to maximize HIV prevention from global scale-up of VCT.
From the aDepartment of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
bBiomedical Research and Training Institute, Harare
cNational Institute of Health Research, Harare
dDepartment of Medical and Laboratory Sciences, University of Zimbabwe, Harare, Zimbabwe.
Received 22 June, 2006
Revised 27 August, 2006
Accepted 27 September, 2006
Correspondence to Dr Liz Corbett, Biomedical Research and Training Institute, National Institute of Health Research, Josiah Tongogara Avenue, PO Box CY 1753 Causeway, Harare, Zimbabwe. E-mail: firstname.lastname@example.org