Jonathan J. JulianoFrederic ArieyRithy SemNoppadon TangpukdeeSrivicha KrudsoodCarol OlsonSornchai LooareesuwanWilliam O. RogersChansuda WongsrichanalaiSteven R. MeshnickSchool of MedicineThe University of North Carolina at Chapel HillLmmtech PharmaceuticalsInstitut Pasteur du CambodgeMahidol UniversityNaval Medical Research Unit No2018-09-132018-09-132009-08-15Journal of Infectious Diseases. Vol.200, No.4 (2009), 624-628002218992-s2.0-69149107186https://repository.li.mahidol.ac.th/handle/20.500.14594/27981Most trials of antimalarials occur in areas in which reinfections are possible. For Plasmodium falciparum, reinfections are distinguished from recrudescences by polymerase chain reaction analysis of 3 polymorphic genes. However, the validity of this approach has never been rigorously tested. We tested for misclassification in 6 patients from clinical trials in Thailand and Cambodia who were classified as being reinfected by the standard polymerase chain reaction protocol. Using heteroduplex tracking assays and direct DNA sequencing, we found that 5 (83%) of 6 patients were misclassified. Misclassification in this manner overestimates the efficacy of antimalarials and delays the recognition of decreasing therapeutic efficacy, thus delaying potential changes in policy. © 2009 by the Infectious Diseases Society of America. All rights reserved.Mahidol UniversityMedicineArticleSCOPUS10.1086/600892