HIV This Week

Lindenburg CE, Krol A, et al. Decline in HIV incidence and injecting, but not in sexual risk behaviour, seen in drug users in Amsterdam: a 19-year prospective cohort study. AIDS 2006;20:1771-75.

Lindenburg and colleagues studied temporal changes in HIV incidence, HIV transmission routes, and both injecting and sexual risk behaviour in the open Amsterdam Cohort Study among drug users. Initiated in 1985, the Amsterdam Cohort Study enabled the authors to study changes in trends since HAART became widespread in 1996. Person-time techniques were used to study the trend in HIV incidence among HIV-negative drug users. HIV transmission routes were determined using detailed standardised questionnaires. Trends in injecting and sexual risk behaviours were evaluated with a logistic regression model adjusted for correlations between visits of the same individual. The 1315 HIV-negative individuals, of whom 93 seroconverted for HIV, yielded 6970 HIV-negative person-years of follow-up. The HIV incidence was 7 per 100 person-years in 1986 and fell so that after 1999 it varied between 0 and 0.5 per 100 person-years. The odds ratio was 15.6 (95% CI 2.6-94.6) for HIV transmission through unprotected heterosexual contact versus injecting after 1996 compared with the period before. Reports of both injecting and borrowing needles significantly declined over the period 1985-2004. Reports of sexual risk behaviour and sexually transmitted infections at follow-up visits decreased before, but not after, 1996. The authors conclude that the HIV incidence among drug users in the Amsterdam Cohort Study has declined since 1985. Accompanied by a reduction in injecting drug use and needle sharing, this decline occurred despite continued sexual risk behaviour. At present, new HIV seroconversions are related mainly to unprotected heterosexual contacts. Therefore, HIV prevention programmes for drug users should pay specific attention to the importance of safer sex practices.

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Hoffmann O, Boler T, Dick B. Achieving the global goals on HIV among young people most at risk in developing countries: young sex workers, injecting drug users and men who have sex with men. World Health Organ Tech Rep Ser 2006;938:287-315.Hoffmann and colleagues undertook a systematic literature review to identify programmes in low- and middle-income countries for young people in the three selected groups most at risk from HIV: young sex workers, injecting drug users, and men who have sex with men. The authors also identified programmes directed at young people in developed countries as well as programmes in low- and middle-income countries for these three population groups that did not differentiate between young people and adults. Young people 10 to 24 years of age represent a large proportion of the population most at risk of becoming infected with HIV in low- and middle-income countries. Despite this fact, well documented evaluations of programmes for these groups are scarce. However, there is evidence of effectiveness for programmes that are facility-based and use outreach to provide information and services to at-risk young people. The authors conclude that there is growing evidence from low- and middle-income countries of successful initiatives for groups most at risk from HIV, and these programmes should be widely implemented provided that they are carefully planned and monitored and have a strong evaluation component. However, there is an urgent need to disaggregate data by age in order to determine how effective these programmes are in reaching young people and to better understand the specific needs of at-risk young people as opposed to older age groups.