James D Shelton

Risk compensation: the Achilles' heel of innovations in HIV prevention?

The benefits of new methods of prevention of HIV could be jeopardised if they are not accompanied by efforts to change risky behaviour

Partner reduction is crucial for balanced “ABC” approach to HIV prevention

Behaviour change programmes to prevent HIV have mainly promoted condom use or abstinence, while partner reduction remains the neglected component of ABC The key to preventing the spread of HIV, especially in epidemics driven mainly by heterosexual transmission, is through changing sexual behaviour. Interest has been growing in an “ABC” approach in which A stands for abstinence or delay of sexual activity, B for be faithful, and C for condom use (box).1 Although “be faithful” literally implies monogamy, it also includes reductions in casual sex and multiple sexual partnerships (and related issues of partner selection) that would reduce higher risk sex. While most of the often polarised discussion surrounding AIDS prevention has focused on promoting abstinence or use of condoms,w1 w2 partner reduction has been the neglected middle child of the ABC approach. It seems obvious, but there would be no global AIDS pandemic were it not for multiple sexual partnerships. The rate of change of sexual partners—especially concurrent partners—is a crucial determinant in the spread of sexually transmitted infections,w3 including HIV.2 Moreover, HIV viral load and therefore infectiousness is dramatically higher during the early (acute) stage of HIV infection,3 so transmission would be particularly heightened by partner change among newly infected people. Transmission of HIV is also facilitated by the presence of other sexually transmitted infections, especially ulcerative ones.w4 Hence, increased risk of other sexually transmitted infections from multiple partnerships further magnifies the spread of HIV. ### ABC of sexual behaviour change A = abstinence or delay of sexual activity B = be faithful (including partner reduction and avoiding high risk partners) C = condom use, particularly for high risk sex Partner reduction seems to have been pivotal to success in two countries heralded for reversing their HIV epidemics, Thailand and Uganda. Thailands “100% condom” approach in brothels is …

Is poverty or wealth at the root of HIV

Poverty and lack of economic opportunity are commonly cited as important contributors to the AIDS epidemic. Indeed an essay in The Lancet last year asked whether poverty reduction was the only sustainable solution to preventing AIDS. Thus recent findings from the Tanzania 2003–04 HIV/AIDS indicator survey may come as a surprise. The evidence is just the opposite (figure). This nationally representative survey measured wealth in terms of physical characteristics of the household and household possessions. Household wealth is strongly positively related to HIV prevalence. Indeed the difference in prevalence for women between the lowest and highest wealth quintile is four-fold. These findings are similar to those reported for Kenya last year. Notably HIV prevalence is highest in some of the most economically advanced countries in Africa (eg South Africa Botswana). A positive relation between wealth and HIV risk has been noted before but has been upstaged by the focus on poverty. (excerpt)

Risk of clinical pelvic inflammatory disease attributable to an intrauterine device

Use of the intrauterine device (IUD) is avoided because of perceived risk of pelvic inflammatory disease (PID) associated with sexually transmitted Infections (STI). Calculation of the risk of clinical pelvic inflammatory disease showed that the estimated risk was low (0.15%), even with a high STI prevalence. This estimated risk argues for making IUDs more available.

Ten myths and one truth about generalised HIV epidemics

Despite substantial progress against AIDS worldwide we are still losing ground. The number of new infections continues to dwarf the numbers who start antiretroviral therapy in developing countries. Most infections occur in widespread or generalised epidemics in heterosexuals in just a few countries in southern and eastern Africa. Although HIV incidence has fallen in Uganda Kenya and Zimbabwe the generalised epidemic rages on. Something is not working. Ten misconceptions impede prevention. (excerpt)

Concurrency revisited: increasing and compelling epidemiological evidence

Multiple sexual partnerships must necessarily lie at the root of a sexually transmitted epidemic. However, that overlapping or concurrent partnerships have played a pivotal role in the generalized epidemics of sub-Saharan Africa has been challenged. Much of the original proposition that concurrent partnerships play such a role focused on modelling, self-reported sexual behaviour data and ethnographic data. While each of these has definite merit, each also has had methodological limitations. Actually, more recent cross-national sexual behaviour data and improved modelling have strengthened these lines of evidence. However, heretofore the epidemiologic evidence has not been systematically brought to bear. Though assessing the epidemiologic evidence regarding concurrency has its challenges, a careful examination, especially of those studies that have assessed HIV incidence, clearly indicates a key role for concurrency.Such evidence includes: 1) the early and dramatic rise of HIV infection in generalized epidemics that can only arise from transmission through rapid sequential acute infections and thereby concurrency; 2) clear evidence from incidence studies that a major portion of transmission in the population occurs via concurrency both for concordant negative and discordant couples; 3) elevation in risk associated with partners multiple partnering; 4) declines in HIV associated with declines in concurrency; 5) bursts and clustering of incident infections that indicate concurrency and acute infection play a key role in the propagation of epidemics; and 6) a lack of other plausible explanations, including serial monogamy and non-sexual transmission. While other factors, such as sexually transmitted infections, other infectious diseases, biological factors and HIV sub-type, likely play a role in enhancing transmission, it appears most plausible that these would amplify the role of concurrency rather than alter it. Additionally, critics of concurrency have not proposed plausible alternative explanations for why the explosive generalized epidemics occurred. Specific behaviour change messaging bringing the concepts of multiple partnering and concurrency together appears salient and valid in promoting safer individual behaviour and positive social norms.

The contribution of HIV-discordant relationships to new HIV infections in Rakai, Uganda

We determined HIV infections in the Rakai cohort before (82/9434) and after (131/13082) the availability of antiretroviral therapy (ART). The proportions of total HIV infections pre-ART and post-ART were 18.3% and 13.7%, respectively, among identifiable HIV-discordant couples, 23.2% and 26.0%, respectively, in concordant HIV-negative couples, 29.3% and 17.6% in married persons with unknown partner status, and 29.3% and 42.7% in the unmarried. Voluntary counseling and testing targeting discordant couples is unlikely to have a substantial impact in this setting.

Why multiple sexual partners

This article addresses multiple sexual partnerships specifically as the root of the generalized epidemic of HIV in southern and eastern Africa. It discusses the many reasons for multiple sexual partners for men and women as well as shares project initiatives and campaigns focused on behavior change communication to end this crisis in Africa.

Empirically based conversion factors for calculating couple-years of protection.

Couple-years of protection (CYP) is one of several commonly used indicators to assess international family planning efforts. It has been the subject of much debate, relating in part to the specific conversion factors used to translate the quantity of the respective contraceptive methods distributed to a single measure of protection. This article outlines a comprehensive effort to revisit those conversion factors based on the best available empirical evidence. In most instances, the analysis supports previously established standard conversion factors. However, there are two notable departures. Fewer condoms and spermicides are recommended for each CYP (120 vs. 150), primarily because coital frequency among condom users is lower than previously assumed. Furthermore, for sterilization, the authors recommend the use of country or region-specific conversion factors. Every program evaluation indicator has strengths and weaknesses, and the best program evaluation efforts use a variety of indicators. If CYP is used to evaluate programs, however, the authors believe that the conversion factors presented reflect the best available evidence.

Has global HIV incidence peaked

Rajesh Kumar and colleagues in todays Lancet document a declining prevalence of HIV-1 in young adults in South India. This evidence along with other recent positive findings provides impetus to re-examine the HIV pandemic. Many readers may be surprised that available evidence indicates that HIV incidence (rate of new infections) has peaked overall in Africa--indeed it did so some years ago. And even the lagging indicator of HIV prevalence (rate of existing infections) has also declined in an increasingly impressive number of African settings and elsewhere. One reason that this decline in incidence is poorly appreciated is because attention often focuses on prevalence. To understand the interplay of HIV incidence and prevalence Kenya is illustrative. According to modelling by the US Census Bureau new infections peaked around 1992-93. However because of the many years of latency between HIV infection and mortality prevalence continued to rise even as incidence fell--and peaked around 1997 when mortality finally rose to match incidence. (excerpt)