HIV-2 infections in a rural Senegalese community

The importance of interdisciplinary collaborative research in responding to HIV/AIDS vulnerability in rural Senegal

HIV prevalence in Senegal is less than 1%, a success generally attributed to the country's quick response to the nascent epidemic of the 1980s and its continued efforts to curtail the spread of HIV. However, as the bulk of the healthcare infrastructure and support for HIV-positive individuals and AIDS patients are located in urban areas, there remains limited information on HIV and AIDS prevalence in rural areas. Several focus group discussions held with small-holder farmers in 2006, in the regions of Kolda and Tambacounda, Senegal, in the framework of a regional food-security development programme, revealed the growing vulnerability of rural populations to HIV and AIDS. Because current HIV/AIDS campaigns are strongly influenced by generalised, internationally formulated guidelines that fail to take into account the cultural particularities of the Senegalese context, the initial positive impact of these campaigns has dramatically decreased and at-risk behaviour in rural Senegal has been found to be on the increase. The article argues that in order for HIV/AIDS campaigns to have an impact there is an urgent need for evidence-based approaches built on a deeper understanding of the local socio-cultural situation through interdisciplinary research and collaboration.

Declining HIV-2 prevalence and incidence among men in a community study from Guinea-Bissau

OBJECTIVE

To assess the present level of HIV-2 infection in an adult population in Bissau and to evaluate sex and age-specific changes in HIV-2 prevalence and incidence between 1987 and 1996.

DESIGN AND METHODS

Sex and age-specific changes in HIV-2 prevalence were evaluated comparing a survey from 1987 in a sample of 100 houses with a survey performed in 1996 in an independent sample of 212 houses from the same study area. HIV-2 incidence rates were examined in an adult population (age > or = 15 years) from 100 randomly selected houses followed with four consecutive HIV serosurveys from 1987 to 1996.

RESULTS

The HIV-2 prevalence in 1996 was 6.8% (men, 4.7%; women, 8.4%). Compared with the 1987 survey there was a significant decrease in prevalence among men [age-adjusted relative risk (RR), 0.50; 95% confidence interval (CI), 0.31-0.83], whereas it remained unchanged in women (RR, 1.00; 95% CI, 0.67-1.48). The male-to-female RR decreased from 0.99 (95% CI, 0.61-1.61) in 1987 to 0.51 (95% CI, 0.34-0.76) in 1996. The overall annual incidence rate was 0.54 per 100 person-years of observation (PYO), being higher in women (0.72 per 100 PYO) than in men (0.31 per 100 PYO). With the observation time divided into an early and a late period, there was a decrease in incidence with time among men (0.66 to 0.00 per 100 PYO), but no major change among women (0.59 to 0.85 per 100 PYO). The two trends differed significantly (P = 0.03). We observed a higher annual incidence rate amongst older women aged > 44 years (1.77 per 100 PYO) than among younger women (0.55 per 100 PYO; P = 0.05).

CONCLUSION

There are no signs of an epidemic spread of HIV-2 in Bissau even though the HIV-1 prevalence is increasing rapidly. A significant reduction in the male HIV-2 prevalence and incidence rates has resulted in a major shift in the pattern of spread of HIV-2, from being equally distributed to being predominantly a female infection. Currently, older women in particular seem to have a high risk of getting infected.