DISTRIBUTION OF PFCRT HAPLOTYPES AND IN-VIVO EFFICACY OF CHLOROQUINE IN TREATMENT OF UNCOMPLICATED P. FALCIPARUM MALARIA BEFORE DEPLOYMENT OF ARTEMISININ COMBINATION THERAPIES IN URBAN POPULATION OF KOLKATA, INDIA

A total of 101 P. falciparum positive patients were enrolled from urban population of Kolkata, India to determine the therapeutic efficacy of chloroquine as per 28 days follow-up schedule of WHO, 2003. All parasite strains were analyzed for P. falciparum chloroquine resistance transporter (pfcrt) haplotypes using DNA sequencing methodology. The PCR corrected chloroquine resistant P. falciparum was very high (76.3%, 95% CI 0.642 – 0.832) of which early treatment failure was (10%), and late treatment failure was (66.3%). K76T mutation was found in all parasite strains irrespective of therapeutic outcomes. Both the Venezuelan (SVMNT) and Southeast Asian (CVIET) haplotypes were prevalent in the study population with predominance of South East Asian haplotype (87.1%). The present study showed that incidence of CQ resistant P. falciparum malaria in Kolkata was very high and well above the WHO recommended cut-off level for change of drug policy. Recently introduced Artimisinine Combination Therapy by the Government of India to treat all P. falciparum cases is an appropriate step.