A variety of epidemiologic studies are being conducted in Kenya. Studies in the Kisumu area of western Kenya are evaluating how the genetic diversity of Plasmodium falciparum parasites affects the risk of severe disease. On the coast of Kenya, in Kilifi District, a series of studies have documented that extremely low levels of P. falciparum transmission by Anopheles gambiae are associated with high rates of severe disease in children less than six years of age. We are now initiating epidemiologic studies in the highland areas of Kenya that will employ unique disease surveillance capabilities to detect and monitor seasonal epidemics of P. falciparum malaria. We are conducting studies of mosquito ecology and behavior to assess the current potential for the re-emergence of malaria.
Experimental studies focus on vector competence, blood-feeding behavior, and digestive physiology.
Corresponding field studies are evaluating changes in vector distribution and abundance associated with changes in land use, especially with respect to rice irrigation and deforestation. Research in Latin America Studies in Colombia are designed to examine the clonality of relapse in Plasmodium vivax infection. The polymerase chain reaction is extremely useful for studies of clonality because filter paper blots remain stable at ambient temperature under field conditions in the tropics. These studies have shown that natural P. falciparum infection is often polyclonal, with as many as three different clones present in the blood of a single child simultaneously. A major research interest of Dr. Wiser's laboratory is molecular and cellular biology of host-parasite interactions.