Malaria elimination in Malawi: research needs in highly endemic, poverty-stricken contexts

Abstract

Malaria control in the impoverished, highly endemic settings of sub-Saharan Africa remains a major public health challenge. Successes have been achieved only where sustained, concerted, multi-pronged interventions have been instituted. As one of the world's poorest countries, Malawi experiences malaria incidence rates that have remained high despite a decade of gradually expanding and more intensive prevention efforts. The Malawi International Center for Excellence in Malaria Research (ICEMR) is beginning work to augment the knowledge base for reducing Plasmodium transmission and malaria morbidity and mortality. Among ICEMR goals, we intend to better assess patterns of infection and disease, and analyze transmission by Anopheles vector species in both urban and rural ecological settings. We will evaluate parasite population genetics and dynamics, transmission intensities and vector ecologies, social and environmental determinants of disease patterns and risk, and human-vector-parasite dynamics. Such context-specific information will help to focus appropriate prevention and treatment activities on efforts to control malaria in Malawi. In zones of intense and stable transmission, like Malawi, elimination poses particularly thorny challenges - and these challengers are different from those of traditional control and prevention activities. Working toward elimination will require knowledge of how various interventions impact on transmission as it approaches very low levels. At present, Malawi is faced with immediate, context-specific problems of scaling-up prevention and control activities simply to begin reducing infection and disease to tolerable levels. The research required to support these objectives is critically evaluated here.

Figure 1

Prevalence of Plasmodium parasitemia in Malawian children under five years old during 2010. Data are from systematic, nationwide surveillance by the Malaria Indicator Survey (National Malaria Control Program, 2010)

Figure 2

Prevalence of Plasmodium parasitemia among Malawians residing in three regions of the country during 2010. Data are from systematic, nationwide surveillance by the Malaria Indicator Survey (National Malaria Control Program, 2010)

Figure 3

Number of presumptive cases of malaria diagnosed throughout Malawi during July 2004–June, 2005 (red), and July 2006–June 2007 (black) grouped by ages less than 5 years old (dashed) and 5 or more years old (solid). Data are from Malaria Indicator Surveys (Malawi Ministry of Health, 2005a, 2010b)