title: Chloroquine-resistant Plasmodium falciparum infections among UK travellers returning with malaria after chloroquine prophylaxis.
abstract: OBJECTIVE
  We sought to identify chloroquine-resistant Plasmodium falciparum parasites among 66 travellers who presented in the UK with malaria.
  
  
  METHODS
  A multiplex real-time PCR assay was devised to identify wild-type and two distinct chloroquine-resistance-associated alleles of the pfcrt gene.
  
  
  RESULTS
  Those with documented use of chloroquine/proguanil prophylaxis were more likely to carry parasites with resistance-associated alleles of pfcrt than were patients who had been using antimalarials other than chloroquine (92.9% versus 37.5%; P = 0.011). We also found evidence that people reporting optimum compliance with chloroquine prophylaxis during malaria exposure were more common among malaria cases than were those reporting optimum compliance with other regimens (OR 3.85, 95% CI 1.61-9.69; P = 0.0008).
  
  
  CONCLUSIONS
  Chloroquine, known to be failing as therapy for falciparum malaria worldwide, is also failing to provide adequate malaria prophylaxis for travellers.
authors.affiliation: Hospital for Tropical Diseases, London, UK. colin.sutherland@lshtm.ac.uk
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Sutherland
authors.forename: Thomas
authors.initials: T
authors.lastname: Haustein
authors.forename: Nahla
authors.initials: N
authors.lastname: Gadalla
authors.forename: Margaret
authors.initials: M
authors.lastname: Armstrong
authors.forename: Justin F
authors.initials: JF
authors.lastname: Doherty
authors.forename: Peter L
authors.initials: PL
authors.lastname: Chiodini
mesh_terms: D000483:Alleles; D000818:Animals; D002738:Chloroquine / Q000494:pharmacology* / Q000627:therapeutic use*; D004351:Drug Resistance; D005838:Genotype; D006801:Humans; D016778:Malaria, Falciparum / Q000469:parasitology* / Q000517:prevention & control*; D026901:Membrane Transport Proteins / Q000235:genetics; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000235:genetics; D002727:Proguanil / Q000494:pharmacology; D015800:Protozoan Proteins / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D006113:United Kingdom / Q000453:epidemiology
chemical_list: D026901:Membrane Transport Proteins; C416369:PfCRT protein, Plasmodium falciparum; D015800:Protozoan Proteins; D002738:Chloroquine; D002727:Proguanil