Chloroquine resistant Plasmodium vivax malaria in India.

In India, 1.2-1.5 million new cases of Plasmodium vivax occur each year. These cases are successfully treated with 600 mg chloroquine (adult dose). We report the results of malaria treatment of a 13-year-old girl from the Indian Oil Corporation (IOC), Mathura, India who contracted P. vivax infection. The infection failed to respond to 2 cycles of standard chloroquine therapy. The concentrations of chloroquine were monitored with high performance liquid chromatography (HPLC). The plasma and whole blood chloroquine concentrations were 260 and 106 micrograms/l respectively, while a 15 micrograms/l plasma concentration is considered lethal to P. vivax. Resistance in P. vivax to chloroquine was found at the IOC, Mathura.