Plasmodium yoelii

Plasmodium yoelii is a parasite of the genus "Plasmodium" subgenus "Vinckeia". As in all "Plasmodium" species, "P. yoelii" has both vertebrate and insect hosts. The vertebrate hosts for this parasite are mammals.
Taxonomy.
This species was described in 1968 by Landau, Michel and Adam. Three subspecies are recognised: "P. y. killicki", "P. y. nigeriensis" and "P. y. yoelli".
Distribution.
This species occurs in Africa.
Vectors.
The natural vectors of this species are not currently known. One possible is the female "Anopheles" mosquito which serves as a vector for "Plasmodium vivax".
Hosts.
This species infects "Thamnomys rutilans." 
Notes.
It is used in the laboratory to infect mice, as a model of human malaria, particularly with respect to the immune response. It is advantageous to have a whole-animal model of malaria because often it is difficult to know which factors to study "in vitro", particularly in a complex system like the immune system. Moreover, for many experiments it is not ethical or practical to use humans.
One of the special things about this particular model is that it has two strains with vastly different pathogenicity. These are generally referred to as the "lethal" and "non-lethal" strains of the species. Comparison of these two strains can be used to deduce which factors may contribute to more serious malaria infections in humans.