Monitoring of the therapeutic efficacy of chloroquine for the treatment of uncomplicated, Plasmodium falciparum malaria in Iran.

Between 2002 and 2004, the standardized 28-day protocol recently developed by the World Health Organization was used to explore the efficacy of chloroquine, in the treatment of uncomplicated, Plasmodium falciparum malaria, in five sentinel sites in southern Iran. All but 14 of the 158 patients enrolled (128, 28 and two from the provinces of Sistan-Baluchestan, Hormozgan and Kerman, respectively) were successfully followed-up. The overall frequency of treatment failure by day 28 was 78.5%, with 17.4% of the patients being classed as early treatment failures, 34.7% as late clinical failures, and 26.4% as late parasitological failures. There appeared to be no significant change in the frequency of treatment failure between the 2002-2003 and 2003-2004 transmission seasons, nor any significant between-site variation in the efficacy of chloroquine. Given these observations, the replacement of chloroquine, as the first-line drug for the treatment of uncomplicated, P. falciparum malaria in Iran, was inevitable. Artesunate-sulfadoxine-pyrimethamine is now the recommended first-line treatment, with artemether-lumefantrine used for second-line treatment. The efficacies of these combination therapies are currently being evaluated and monitored.