HIV prevalence in Uganda has dropped 70% since the early 1990s primarily because of a "successful" public HIV/AIDS prevention campaign that encourages avoiding "casual" sexual activity, according to a study published in the April 30 issue of the journal Science, BBC News reports (BBC News, 4/30). Drs. Rand Stoneburner and Daniel Low-Beer of University of Cambridge in the United Kingdom analyzed population-level HIV and behavioural data from Uganda and neighbouring countries -including Kenya, Malawi and Zambia - to assess the validity and determinants of declines in HIV prevalence and examine the potential influences of prevention interventions.