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Description
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MARA is a biological model of Falciparum malaria transmission that sets decision rules which govern
how minimum and mean temperature constrain the development of the parasite and the vector and how
precipitation affects survival and breeding. MARA determined the decision rules by reviewing
laboratory and field studies throughout Sub-Saharan Africa and looking at current malaria
distribution maps.
This biological model approximates the current boundaries of malaria distribution across the
continent quite well. The model uses three variables to determine any geographic location’s
climatic suitability: mean monthly temperature, winter minimum temperature, and total cumulative
monthly precipitation. An important distinction between this model and others is that the MARA
decision rules were developed using fuzzy logic to resolve the uncertainty in defining distinct
boundaries dividing malarious from nonmalarious regions.
The MARA/ARMA decision rules stipulate that both temperature and precipitation have to be favorable
at the same time of the year to allow transmission, and suitable conditions have to continue long
enough for the transmission cycle to be completed. Five months were considered a sufficient length
of time for conditions to be suitable for stable transmission. MARA LITe is a stand-alone query
system of the MARA database. MARA LITe converts the MARA relational database (29 separate tables)
into a flat structure.
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References
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See http://www.mara.org.za/ for references
Craig M.H., R.W. Snow, and D. le Sueur. 1999. A climate-based distribution model of malaria
transmission in sub-Saharan Africa. Parasitology Today 15:105-111.
Snow R.W., M. Craig, U. Deichmann, and K. Marsh. 1999. Estimating mortality, morbidity, and
disability due to malaria among Africa’s non-pregnant population. Bull. WHO 77:624-640.
Hartman, J., K.L. Ebi, J.K. McConnell, N. Chan, and J. Weyant. 2002. Climate suitability for stable
malaria transmission in Zimbabwe under different climate change scenarios. Global Change and Human
Health 3:2-14.
Kleinschmidt, I., J. Omumbo, O. Briet, N. van de Giesen, N. Sogoba, N.K. Mensa, P. Windmeijer, M.
Moussa, and T. Teuscher. 2001. An empirical malaria distribution map for West Africa. Trop Med Int
Health 6:779-786.
Gemperli A., P. Vounatsou, I. Kleinschmidt, M. Bagayoko, C. Lengeler, and T. Smith. 2004. Spatial
patterns of infant mortality in Mali: The effect of malaria endemicity. Am J Epidemiol 159:64-72.
MARA/ARMA. 1998. Towards an atlas of malaria risk in Africa. Durban, South Africa.
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