In-vivo and in-vitro sensitivity of Plasmodium falciparum to chloroquine in Chennai (Tamil Nadu), India.

Abstract

In-vitro and in-vivo susceptibility of Plasmodium falciparum to chloroquine were conducted at Chennai city, India. Eighteen (60%) out of 30 cases showed resistance in in-vitro study. EC50 of resistant and sensitive cases were 0.40 and 0.24 mumol chloroquine/l blood respectively, while EC90 were 2.64 and 0.84 mumol chloroquine/l blood respectively. In-vivo tests identified 24 cases (40%) as resistant (23 RI and 1 RII) and 36 (60%) as sensitive out of 60 cases. Eight isolates which were found resistant with in-vitro tests showed sensitive behaviour to chloroquine treatment assessed by in-vivo studies.