Drug resistance in malaria: three cases and a review.

Drug resistance has been well documented in two species of malarial parasites. Of greatest concern are the rapid developments in the resistance of Plasmodium falciparum to commonly used therapeutic and chemoprophylactic agents. This species, which is capable of producing life-threatening disease, has shown various levels of resistance in different parts of the world. Also, some strains of the most common species causing relapsing disease, P. vivax, exhibit resistance to primaquine. Three cases of malaria that demonstrate various types of drug resistance are presented in this paper.