Scientific Findings of the Southern and Central Africa International Center of Excellence for Malaria Research: Ten Years of Malaria Control Impact Assessments in Hypo-, Meso-, and Holoendemic Transmission Zones in Zambia and Zimbabwe
Matthew M. Ippolito, Mary E. Gebhardt, Ellen Ferriss, Jessica L. Schue, Tamaki Kobayashi, Mike Chaponda, Jean-Bertin Bukasa Kabuya, Mbanga Muleba, Monicah M. Mburu, Japhet Matoba, Michael Musonda, Ben Katowa, Mukuma Lubinda, Harry Hamapumbu, Limonty Simubali, Twig Mudenda, Amy Wesolowski, Timothy M. Shields, Andre Hackman, Clive Shiff, Maureen Coetzee, Lizette L. Koekemoer, Shungu Munyati, Lovemore Gwanzura, Susan Mutambu, Jennifer C. Stevenson, Philip E. Thuma, Douglas E. Norris, Jeffrey A. Bailey, Jonathan J. Juliano, Gershom Chongwe, Modest Mulenga, Edgar Simulundu, Sungano Mharakurwa, Peter Agre, William J. Moss, _ _
Abstract
For a decade, the Southern and Central Africa International Center of Excellence for Malaria Research has operated with local partners across study sites in Zambia and Zimbabwe that range from hypo- to holoendemic and vary ecologically and entomologically. The burden of malaria and the impact of control measures were assessed in longitudinal cohorts, cross-sectional surveys, passive and reactive case detection, and other observational designs that incorporated multidisciplinary scientific approaches: classical epidemiology, geospatial science, serosurveillance, parasite and mosquito genetics, and vector bionomics. Findings to date have helped elaborate the patterns and possible causes of sustained low-to-moderate transmission in southern Zambia and eastern Zimbabwe and recalcitrant high transmission and fatality in northern Zambia. Cryptic and novel mosquito vectors, asymptomatic parasite reservoirs in older children, residual parasitemia and gametocytemia after treatment, indoor residual spraying timed dyssynchronously to vector abundance, and stockouts of essential malaria commodities, all in the context of intractable rural poverty, appear to explain the persistent malaria burden despite current interventions. Ongoing studies of high-resolution transmission chains, parasite population structures, long-term malaria periodicity, and molecular entomology are further helping to lay new avenues for malaria control in southern and central Africa and similar settings.