Preliminary investigation found that a large outbreak of influenza-like illness occurred in Madagascar during July-August 2002, with 30 304 cases and 754 deaths reported. Most cases were reported from the highland regions of Fianarantsoa Province, in centre Madagascar. The majority of the cases lived in rural areas, and children under five years and adults 60 years and older were the most affected. The outbreak was attributable to an A/Panama/2007/99-like (H3N2) virus, which has been circulating worldwide for several years.