Malaria Molecular Epidemiology: Lessons from the International Centers of Excellence for Malaria Research Network
van Eijk, AMA
Permanent link to this recordhttp://hdl.handle.net/20.500.12613/5206
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Abstract© The American Society of Tropical Medicine and Hygiene. Molecular epidemiology leverages genetic information to study the risk factors that affect the frequency and distribution of malaria cases. This article describes molecular epidemiologic investigations currently being carried out by the International Centers of Excellence for Malaria Research (ICEMR) network in a variety of malaria-endemic settings. First, we discuss various novel approaches to understand malaria incidence and gametocytemia, focusing on Plasmodium falciparum and Plasmodium vivax. Second, we describe and compare different parasite genotyping methods commonly used in malaria epidemiology and population genetics. Finally, we discuss potential applications of molecular epidemiological tools and methods toward malaria control and elimination efforts.
Citation to related workAmerican Society of Tropical Medicine and Hygiene
Has partThe American journal of tropical medicine and hygiene
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The spatial and temporal patterns of falciparum and vivax malaria in Per: 19942006Chowell, G; Munayco, CV; Escalante, AA; McKenzie, FE (2009-08-14)Background. Malaria is the direct cause of approximately one million deaths worldwide each year, though it is both preventable and curable. Increasing the understanding of the transmission dynamics of falciparum and vivax malaria and their relationship could suggest improvements for malaria control efforts. Here the weekly number of malaria cases due to Plasmodium falciparum (19942006) and Plasmodium vivax (19992006) in Per at different spatial scales in conjunction with associated demographic, geographic and climatological data are analysed. Methods. Malaria periodicity patterns were analysed through wavelet spectral analysis, studied patterns of persistence as a function of community size and assessed spatial heterogeneity via the Lorenz curve and the summary Gini index. Results. Wavelet time series analyses identified annual cycles in the incidence of both malaria species as the dominant pattern. However, significant spatial heterogeneity was observed across jungle, mountain and coastal regions with slightly higher levels of spatial heterogeneity for P. vivax than P. falciparum. While the incidence of P. falciparum has been declining in recent years across geographic regions, P. vivax incidence has remained relatively steady in jungle and mountain regions with a slight decline in coastal regions. Factors that may be contributing to this decline are discussed. The time series of both malaria species were significantly synchronized in coastal ( = 0.9, P < 0.0001) and jungle regions ( = 0.76, P < 0.0001) but not in mountain regions. Community size was significantly associated with malaria persistence due to both species in jungle regions, but not in coastal and mountain regions. Conclusion. Overall, findings highlight the importance of highly refined spatial and temporal data on malaria incidence together with demographic and geographic information in improving the understanding of malaria persistence patterns associated with multiple malaria species in human populations, impact of interventions, detection of heterogeneity and generation of hypotheses. © 2009 Chowell et al.