Chloroquine-resistant Plasmodium falciparum with reduced sensitivity in vitro to mefloquine and quinine in Zaria, northern Nigeria

Abstract

Thirty-six P. falciparum isolates collected from children with malaria were tested for their susceptibility to chloroquine, mefloquine and quinine in vitro using the WHO microtest system. 37% of the isolates grew in the presence of 1.6 mumol chloroquine 1(-1) blood, indicating resistance. The sensitivity to both mefloquine and quinine was markedly reduced. The inhibitory endpoints for quinine correlated with those for chloroquine and mefloquine, but no such correlation was found between chloroquine and mefloquine.