Intravaginal practices in Tanzania and Uganda: Relationships with the vaginal microenvironment, HIV and other STIs

The human immunodeficiency virus (HIV) infects 25 million people in sub-Saharan Africa ? roughly two-thirds of the HIV infections worldwide. The greatest burden is shouldered by 13.3 million African women, who make up 60% of the epidemic in this region. Heterosexual intercourse continues to be the main mode of transmission, and there is strong evidence that some sexual behaviours can increase the risk of HIV infection. We are interested in looking at one set of common female behaviours called intravaginal practices to see if these might be a risk factor for HIV.

Intravaginal practices (IVP) involve putting something inside the vagina to clean, dry, or tighten the vagina. Scientists are concerned that these behaviours may cause tiny cuts or swelling in the vagina that could increase the risk of HIV infection. So far, studies have shown that many women in Africa use these practices, but the evidence linking IVP to HIV risk is still unclear. Studies have also shown that these practices are very different from community to community, and this makes looking at the HIV risk very difficult. Studies must carefully define IVP in each community, so that they can accurately link it to HIV infection.

Working with our collaborative partners in Africa, we have designed a multi-disciplinary study to see if IVP is a risk factor for HIV infection. We will invite women who work in bars and other food and recreational facilities in the city of Kampala in Uganda and small towns in northwest Tanzania to join the study and they will be followed up for one year. The main point of this study is to measure the risk of HIV among IVP users, but it will also study the types of IVP and the reasons women use these practices. In addition, this study will use clinical observations and laboratory tests to look in detail at whether IVP causes swelling or small cuts inside the vagina. This holistic approach is important, because if there is an increased risk of HIV from IVP, we will be able to give clear information on why women are using these practices and how they affect the vagina. This could provide the foundation for programmes to encourage women to change their IVP behaviour and help decrease the risk of HIV.

In sub-Saharan Africa, 60% of the HIV epidemic is shouldered by women. Research is needed to better understand potential risk factors for HIV infection among women. Intravaginal practices (IVP) are common in Africa and have been shown to be associated with HIV in some cross-sectional studies. The only two prospective studies investigating these behaviours in Africa have shown conflicting results. More prospective studies are needed to investigate the effects of IVP on HIV incidence.

The proposed IVP Study will be nested within a large microbicide feasibility study (FS) in Tanzania and Uganda. A total of 1500 HIV-negative women working in high-risk occupations will be recruited to the cohort and followed up every three months for 12 months. The study objectives are to 1) describe and quantify IVP use within the study populations; 2) measure the effect of IVP use on incident HIV infection; and 3) investigate the effect of IVP on the vaginal microenvironment. Two sub-studies will be carried out to investigate IVP behaviours in more detail and to examine causal mechanisms for IVP effects.

IVP-related questions will be developed, pre-tested and incorporated in the FS questionnaire. Cervicovaginal lavage specimens will be collected every six months and used to quantify levels of inflammatory cytokines (IL-1b, IL-RA, IL-6, IL-8, TNF-a and TNF-Receptor II) and inflammatory leukocytes. Tests will be carried out for vaginal flora changes (bacterial vaginosis, Candida overgrowth) and sexually transmitted infections (STIs). The association of IVP with HIV incidence will be investigated, controlling for potential behavioural and biological confounding factors. Further analyses will explore the association between IVP, biomarkers of inflammation, BV and other STIs.

In the Coital Diary and Interview Sub-study, a 10% sample of women from the FS cohort will be asked to complete coital diaries daily for six weeks. In-depth interviews of these women will be conducted to explore the nature and sociocultural context of IVP in more detail.

In the Colposcopy and Inflammatory Biomarker Sub-study, 80-100 women from the FS cohort will be selected on the basis of their reported IVP behaviours, with over-sampling of behaviours assumed to carry higher risk. This sub-cohort will be followed up three times per week for four weeks to investigate short-term variations in inflammatory biomarkers and their association with different IVP behaviours. Colposcopic examination will be carried out at the first and last visits, and associations between IVP, colposcopic findings, BV and inflammatory biomarkers examined.