Clinical drug-resistant falciparum malaria acquired from cultured parasites.

This is the first reported infection with Plasmodium falciparum acquired from continuous cultures of these parasites. The strain involved, FCR3, was originally isolated from The Gambia, West Africa, and was initially sensitive to chloroquine in vitro. After nearly 4 years of continuous culture without chloroquine pressure, it became resistant to chloroquine in vitro and in vivo, as demonstrated by the failure of both prophylactic and therapeutic regimens to control an accidental inoculation of parasite-infected erythrocytes.