HIV prevalence and sexual behaviour at older ages in rural Malawi.

Research on HIV infection and sexual behaviour in sub-Saharan Africa typically focuses on individuals aged 15-49 years under the assumption that both become less relevant for older individuals. We test this assumption using data from rural Malawi to compare sexual behaviour and HIV infection for individuals aged 15-49 with individuals aged 50-64 and 65 and over years. Although general declines with age were observed, levels of sexual activity and HIV remained considerable: 26.7% and 73.8% of women and men aged 65+ reported having sex in the last year, respectively; men's average number of sexual partners remained above one; and HIV prevalence is significantly higher for men aged 50-64 (8.9%) than men aged 15-49 (4.1%). We conclude that older populations are relevant to studies of sexual behaviour and HIV risk. Their importance is likely to increase as access to antiretrovirals in Africa increases. We recommend inclusion of adults aged over 49 years in African HIV/AIDS research and prevention efforts.