HIV incidence rates and risk factors for urban women in Zambia: Preparing for a microbicide clinical trial

Objectives: A preparedness study was conducted to evaluate the suitability of sites and populations following the same study procedures intended for a larger scale microbicide efficacy trial. In the process the study evaluated human immunodeficiency virus (HIV) incidence, prevalence, and risk profiles for HIV-acquisition among young women in urban Zambia. Methods: Women aged 16 to 49 years were screened for participation in the study that involved HIV/sexually transmitted infection testing and the assessment of sexual behavioral characteristics. Two hundred thirty-nine eligible women were enrolled and followed up for 12 months. Results: Baseline HIV prevalence at screening was 38.7% (95% CI: 34.2%-43.3%). The highest age-specific prevalence of HIV was 54.1% (95% CI: 46.3%-61.8%) seen in women aged 26 to 34 years. HIV incidence was 2.6% per 100 woman years. Pregnancy rates were high at 17.4 per 100 woman years (95% CI: 12.2-24.1). Conclusion: It was concluded that our general population sample, characterized by high HIV prevalence and ongoing incidence rates despite receiving regular risk reduction counseling and free condoms qualifies for future microbicide studies. A microbicide preparedness study conducted in Lusaka, Zambia found high HIV prevalence and appreciable HIV incidence in a population of women in an urban setting.