ON THE USE OF MATHEMATICAL-MODELS OF MALARIA TRANSMISSION

The key conclusions of several mathematical models of malaria are reviewed with emphasis on their relevance for control. The Ross-Macdonald model of malaria transmission has had major influence on malaria control. One of its main conclusions is that endemicity of malaria is most sensitive to changes in mosquito imago survival rate. Thus malaria can be controlled more efficiently with imagicides than with larvicides. An extension of this model shows that the amount of variability in transmission parameters strongly affects the outcome of control measures and that predictions of the outcome can be misleading. Models that describe the immune response and simulate vaccination programs suggest that one of the most important determinants of the outcome of a vaccine campaign is the duration of vaccine efficacy. Apparently malaria can be controlled only if the duration of efficacy is in the order of a human life-span. The models further predict that asexual stage vaccines are more efficient than transmission-blocking vaccines. Directions for further applications of mathematical models are discussed.