title: A cluster of Plasmodium vivax malaria in an expedition group to Ethiopia: prophylactic efficacy of atovaquone/proguanil on liver stages of P. vivax.
abstract: OBJECTIVE
  Complete prevention of malaria especially Plasmodium falciparum is the goal of prophylaxis. A survey, designed to ascertain reasons behind the choice of malaria prophylaxis, compliance and side effects, and to gather data on acquired malaria, identified a cluster of Plasmodium vivax infection in a cohort of 33 who travelled to Ethiopia on a scientific expedition.
  
  
  METHODS
  A questionnaire based survey of travellers who took part in a scientific survey and rafting expedition in Ethiopia between October and December 2005 on their return from the expedition and two years later.
  
  
  RESULTS
  31 of 33 subjects completed the survey fully. Evidence was obtained on factors influencing choice of, and adherence to prophylaxis and the incidence and type of malaria related to prophylaxis. Over the two year follow up period 32% of travellers developed P. vivax malaria. Of those taking Mefloquine and Doxycycline 50% and 66% respectively developed malaria, compared to none taking Atovaquone/Proguanil as prophylaxis. Awareness and management of malaria was inadequate in several cases. Failure to use Primaquine led to second relapses.
  
  
  CONCLUSIONS
  Within this cluster, prophylaxis against P. falciparum was successful. Widespread failure of prophylaxis against P. vivax malaria was documented despite the use of recommended regimes of known efficacy against the parasite. Atovaquone/Proguanil had the least side effects and afforded the highest protection. Atovaquone/Proguanil may provide previously unrecognised protection against liver stages of P. vivax.
authors.affiliation: Milford Medical Centre, Sea Road, Milford on Sea SO41 0PG, UK.
authors.forename: Alice
authors.initials: A
authors.lastname: Mavrogordato
authors.forename: Andrew M L
authors.initials: AM
authors.lastname: Lever
mesh_terms: D000328:Adult; D000368:Aged; D019072:Antibiotic Prophylaxis; D000962:Antimalarials / Q000627:therapeutic use*; D053626:Atovaquone / Q000627:therapeutic use*; D015331:Cohort Studies; D004338:Drug Combinations; D005002:Ethiopia; D006801:Humans; D015994:Incidence; D016780:Malaria, Vivax / Q000175:diagnosis / Q000188:drug therapy* / Q000517:prevention & control*; D008875:Middle Aged; D002727:Proguanil / Q000627:therapeutic use*; D011795:Surveys and Questionnaires; D014195:Travel; D016896:Treatment Outcome
chemical_list: D000962:Antimalarials; D004338:Drug Combinations; C109496:atovaquone, proguanil drug combination; D002727:Proguanil; D053626:Atovaquone