Borders &Diagnosis &Epidemiology &ITNs Bill Brieger | 30 Sep 2015 05:43 am
Individual and Household Level Risk Factors Associated with Malaria in Mutasa District, Zimbabwe: a Serial Cross-Sectional Study
Mufaro Kanyangarara and her PhD thesis adviser, Luke Mullany of the Johns Hopkins Bloomberg School of Public Health Department of International Health, have been looking into the challenges of controlling and eventually eliminating malaria in a multi-country context in southern Africa. We are sharing abstracts from her pioneering work including the following which explores risk factors on the Zimbabwe-Mozambique order.
Background: Malaria constitutes a major public health problem in Zimbabwe, particularly in the
north and east bordering Zambia and Mozambique. In Manicaland Province in eastern Zimbabwe, malaria transmission is seasonal and unstable. As a result of intensive scale up of malaria interventions, malaria control was successful in Manicaland Province. However, over the past decade, Manicaland Province has reported increased malaria transmission, and the resurgence of malaria in this region has been attributed to limited funding, drug resistance and insecticide resistance. One of the worst affected districts is Mutasa District. The aim of the study was to identify malaria risk factors at the individual and household levels to better understand what is driving factors associated with malaria and consequently enhance malaria control in eastern Zimbabwe.
Methods: Between October 2012 and September 2014, individual demographic data and household characteristics were collected from cross-sectional surveys of 1,116 individuals residing in 316 households in Mutasa District. Factors characterizing the surrounding environment were obtained from remote sensing data. Factors associated with malaria (measured by rapid diagnostic test [RDT]) were identified through univariate and multivariate multilevel logistic regression models.
Results: A total of 74 (6.4%) participants were RDT positive. Parasite prevalence differed by season (10.4% rainy and 2.9% dry, OR 4.52, 95% CI 2.11-9.69). Sleeping under a bednet showed a protective effect against malaria (OR 0.54, 95% CI 0.29-1.00) despite pyrethroid resistance. The household level risk factors protective against malaria were household density (OR 0.89, 95% CI 0.87-0.97) and increasing distance from the border with Mozambique (OR 0.86, 95% CI 0.76-0.97). Increased malaria risk was associated with recent indoor residual spraying (OR 2.30, 95% CI 1.16-4.56).
Conclusions: Malaria risk was concentrated in areas located at a lower household density and in closer proximity to the Mozambique border. Malaria control in these “high risk” areas may need to be enhanced. These findings underscore the need for strong cross-border malaria control initiatives to complement country specific interventions.