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The objective of this study was to assess the performance of 4 biologic tests designed to detect recent HIV-1 infections in estimating incidence in West Africa (BED, Vironostika, Avidity, and IDE-V3). These tests were assessed on a panel of 135 samples from 79 HIV-1-positive regular blood donors from Abidjan, Côte d'Ivoire, whose date of seroconversion was known (Agence Nationale de Recherches sur le SIDA et les Hépatites Virales 1220 cohort). The 135 samples included 26 from recently infected patients (< or =180 days), 94 from AIDS-free subjects with long-standing infection (>180 days), and 15 from patients with clinical AIDS. The performance of each assay in estimating HIV incidence was assessed through simulations. The modified commercial assays gave the best results for sensitivity (100% for both), and the IDE-V3 technique gave the best result for specificity (96.3%). In a context like Abidjan, with a 10% HIV-1 prevalence associated with a 1% annual incidence, the estimated test-specific annual incidence rates would be 1.2% (IDE-V3), 5.5% (Vironostika), 6.2% (BED), and 11.2% (Avidity). Most of the specimens falsely classified as incident cases were from patients infected for >180 days but <1 year. The authors conclude that none of the 4 methods could currently be used to estimate HIV-1 incidence routinely in Côte d'Ivoire but that further adaptations might enhance their accuracy.

The pilot aim was to assess the feasibility and acceptability of undertaking anonymous HIV testing using oral fluid samples as part of a community-based survey of sexual attitudes and lifestyles of black African communities in London. The three components of the study were administered in various venues across London: (1) a cross-sectional self-completion anonymous questionnaire survey, (2) an optional oral fluid sample for anonymous HIV testing and (3) a nested in-depth interview study in a sub-set of respondents. A total of 114 black African men and women were recruited. A large number of African countries were represented among respondents from newly-migrant and well-established communities. The response rate to the oral fluid sample was high at 82% and all samples collected were of sufficient quality to be tested for HIV. In-depth interviews with respondents revealed positive views and experiences about participating in the study whilst understanding of the questionnaire was good. We therefore conclude that anonymous HIV testing as part of a community-based survey is feasible and acceptable, whilst a set of recommendations was produced to refine the survey methodology and questionnaire. Participatory research methods are essential for achieving successful community-based surveys among black Africans in Britain.

The molecular diversity and demographic characteristics among 976 anti-HIV-1-positive heterosexuals attending 15 sexually transmitted infection (STI) clinics participating in an unlinked anonymous HIV prevalence serosurvey in England and Wales during 1997-2000 were investigated. Subtypes were assigned by heteroduplex mobility assay or sequencing of the p17/p24 region of gag and the V3/V4 region of env and by sequencing of the protease gene. Overall, there was no significant change in the subtype distribution, with subtype C accounting for the majority (32%) of subtyped infections. Subtypes B (29%), A (12%), circulating recombinant forms (CRFs, 9%), unique recombinant forms (URFs, 8%), and subtypes D-H (8%) were also detected. Thirty-nine percent of infections in men were with subtype B, whereas subtype C was most common (38%) in women. Logistic regression analyses showed the relative risk (RR) of infection with a non-B subtype, compared with subtype B, to be greater in African-born individuals (RR = 28.9, P < 0.01), among newly diagnosed infections (RR = 3.4, P < 0.01), and in women (RR = 2.4, P < 0.01). These findings indicate a high level of genetic diversity among HIV-infected heterosexual STI clinic attendees in England and Wales. Recently, subtype C has become most prevalent, particularly in younger age groups, suggesting recent acquisition of this viral strain. The high proportion of non-B, CRF, and URF infections among UK-born individuals is consistent with mixing between migrants and UK-born individuals in England and Wales. As migration patterns change, continued monitoring of HIV genetic diversity will aid understanding of transmission patterns.