Resistance to primaquine in Plasmodium gallinaceum, and the problem of resistance to quinoline compounds in malaria parasites.

The occurrence, during the present decade, of resistance to the 4-aminoquinoline compound chloroquine, in infections of Plasmodium falciparum in certain regions of South America and South East Asia, has focused attention upon drug resistance as a problem in the therapeutic treatment of malaria, since this drug is widely used in prophylaxis and treatment of the clinical attack. Resistance to other aminoquinolines has been produced experimentally. As early as 1934 Nauck described the development of resistance to the 8-aminoquinoline compound pamaquin (plasmoquine) in P. knowlesi, an observation confirmed by Fulton & Yorke (1941), and resistance to this compound was also produced in P. gallinaceum (Bishop & McConnachie, 19526). More recently, resistance to the related 8-aminoquinoline primaquine has been produced experimentally in the Chesson strain of P. vivax (Arnold, Alving, dayman & Hochwald, 1961), and in P. berghei (Prakash, Chakrabarti & Choudhury, 1961; Peters, 1965a, 1966). The following account describes the development of a primaquine-resistant strain of P. gallinaceum, its stability, and the effect of other antimalarial drugs upon it; it also describes attempts to produce resistance to chloroquine in this species and discusses the general problem of resistance to aminoquinolines in malaria parasites.