title: Effects of mefloquine usage on genetic polymorphism of Plasmodium falciparum in Thai-Myanmarese border.
abstract: We studied the polymorphism of msp-1, which encodes a major surface protein on the merozoite, isolated from blood samples from western Thailand in 1999. Our study area was a low-transmission area for malaria, where mefloquine has been used as an antimalarial drug since 1994. Forty-nine patients were confirmed to have contracted falciparum malaria twice within 24 weeks. The number of detected haplotypes in 49 patients was 89 at the first diagnosis and 68 at the second diagnosis. The mean number of haplotypes per patient significantly decreased from 1.82 to 1.39 but the frequency distributions of msp-1 haplotypes did not change significantly with the use of mefloquine. Our study strongly suggests that the antigenic diversity of Plasmodium falciparum is retained during mefloquine therapy in low-transmission areas.
authors.affiliation: International Center for Medical Research, Kobe University School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Matsuo
authors.forename: Toshiro
authors.initials: T
authors.lastname: Shirakawa
authors.forename: Pratap
authors.initials: P
authors.lastname: Singhasivanon
authors.forename: Sornchai
authors.initials: S
authors.lastname: Looareesuwan
authors.forename: Masato
authors.initials: M
authors.lastname: Kawabata
mesh_terms: D017677:Age Distribution; D000818:Animals; D001483:Base Sequence; D019353:Endemic Diseases; D006239:Haplotypes; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000453:epidemiology / Q000235:genetics; D015767:Mefloquine / Q000494:pharmacology* / Q000627:therapeutic use; D020066:Merozoite Surface Protein 1 / Q000235:genetics*; D008969:Molecular Sequence Data; D010597:Pharmacogenetics; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D015995:Prevalence; D011336:Probability; D018570:Risk Assessment; D017678:Sex Distribution; D013785:Thailand / Q000453:epidemiology; D016896:Treatment Outcome
chemical_list: D020066:Merozoite Surface Protein 1; D015767:Mefloquine