Leishmania mexicana: effect of concomitant malaria on cutaneous leishmaniasis. Development of lesions in a Leishmania-susceptible (BALB/c) strain of mouse.

Effect of concomitant malaria on cutaneous leishmaniasis. Development of lesions in a Leishmania-susceptible (BALB/c) strain of mouse. Experimental Parasitology 65, 269-276. Symptoms of human leishmaniasis vary greatly, ranging from cryptic infections to cases with fatal sequelae. Factors regulating the severity of the disease are largely undetermined. Malaria coincides geographically with leishmaniasis in many areas and the immunosuppressive effects of malaria are well documented. It is therefore plausible that malaria could enhance the course of concomitant leishmaniasis. Interactions between Leishmania mexicana and Plasmodium yoelii were examined in BALB/c mice. Percentage of blood cells infected with P. yoelii and diameter of footpad lesions caused by L. mexicana were the criteria used to assay for disease severity. L. mexicana and P. yoelii infections were each significantly enhanced in dually infected mice when compared to mice infected with either parasite alone. Mortality rates due to the normally nonlethal P. yoelii were high during concurrent infections.