title: Clinical and molecular surveillance of drug resistant vivax malaria in Myanmar (2009-2016).
abstract: One of the major challenges for control and elimination of malaria is ongoing spread and emergence of drug resistance. While epidemiology and surveillance of the drug resistance in falciparum malaria is being explored globally, there are few studies on drug resistance vivax malaria.
  
  
  
  To assess the spread of drug-resistant vivax malaria in Myanmar, a multisite, prospective, longitudinal study with retrospective analysis of previous therapeutic efficacy studies, was conducted. A total of 906 from nine study sites were included in retrospective analysis and 208 from three study sites in prospective study. Uncomplicated vivax mono-infected patients were recruited and monitored with longitudinal follow-up until day 28 after treatment with chloroquine. Amplification and sequence analysis of molecular markers, such as mutations in pvcrt-O, pvmdr1, pvdhps and pvdhfr, were done in day-0 samples in prospective study.
  
  
  
  Clinical failure cases were found only in Kawthaung, southern Myanmar and western Myanmar sites within 2009-2016. Chloroquine resistance markers, pvcrt-O 'AAG' insertion and pvmdr1 mutation (Y976F) showed higher mutant rate in southern and central Myanmar than western site: 66.7, 72.7 vs 48.3% and 26.7, 17.0 vs 1.7%, respectively. A similar pattern of significantly higher mutant rate of antifolate resistance markers, pvdhps (S382A, K512M, A553G) and pvdhfr (F57L/I, S58R, T61M, S117T/N) were noted.
  
  
  
  Although clinical failure rate was low, widespread distribution of chloroquine and antifolate resistance molecular makers alert to the emergence and spread of drug resistance vivax malaria in Myanmar. Proper strategy and action plan to eliminate and contain the resistant strain strengthened together with clinical and molecular surveillance on drug resistance vivax is recommended.
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea.|Department of Medical Research, Yangon, Myanmar.
authors.forename: Myat Htut
authors.initials: MH
authors.lastname: Nyunt
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea.
authors.forename: Jin-Hee
authors.initials: JH
authors.lastname: Han
authors.affiliation: Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Anhui, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Medical Research, Yangon, Myanmar.
authors.forename: Khin Myo
authors.initials: KM
authors.lastname: Aye
authors.affiliation: Department of Medical Research, Yangon, Myanmar.
authors.forename: Kyin Hla
authors.initials: KH
authors.lastname: Aye
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea.
authors.forename: Seong-Kyun
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Department of Medical Research, Yangon, Myanmar.
authors.forename: Ye
authors.initials: Y
authors.lastname: Htut
authors.affiliation: Department of Medical Research, Yangon, Myanmar.
authors.forename: Myat Phone
authors.initials: MP
authors.lastname: Kyaw
authors.affiliation: Department of Medical Research, Yangon, Myanmar.
authors.forename: Kay Thwe
authors.initials: KT
authors.lastname: Han
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Republic of Korea. etaekhan@gmail.com.
authors.forename: Eun-Taek
authors.initials: ET
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D000962:Antimalarials / Q000494:pharmacology*; D002738:Chloroquine / Q000494:pharmacology*; D004351:Drug Resistance / Q000235:genetics; D005493:Folic Acid Antagonists / Q000494:pharmacology*; D017125:Genes, Protozoan / Q000235:genetics; D006801:Humans; D008137:Longitudinal Studies; D016780:Malaria, Vivax / Q000188:drug therapy / Q000469:parasitology; D009154:Mutation; D002052:Myanmar; D010966:Plasmodium vivax / Q000187:drug effects* / Q000235:genetics; D011446:Prospective Studies; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000962:Antimalarials; D005493:Folic Acid Antagonists; D002738:Chloroquine
keywords: Drug resistance; Malaria; Molecular surveillance; Myanmar; Plasmodium vivax