Relapse of imported vivax malaria despite standard-dose primaquine therapy: an investigation with molecular genotyping analyses

Clin Microbiol Infect 2012; 18: E232E234 Abstract Taiwan CDC investigated four cases of recurrent imported vivax malaria during 20032010. Molecular genotyping results and the lack of inter-episodes travel history indicated that two of the patients, who acquired vivax malaria in Indonesia and the Solomon Islands, respectively, suffered relapses after an interval of 34 months, despite completing standard-dose primaquine therapy (30 mg/day for 14 days) for the first episode. Treatment with a higher dose of primaquine (60 mg/day for 14 days) prevented further relapse in both patients. This finding calls for further monitoring of the therapeutic efficacy of primaquine in treating Plasmodium vivax acquired in southeast Asia and Oceania.