title: Clinical characteristics of imported malaria in Japan: analysis at a referral hospital.
abstract: Imported malaria remains an important problem in Japan. We have reviewed the medical records of 170 cases of malaria in our hospital, which corresponds to 14.9% of the total cases in Japan. The predominant malarial species was Plasmodium falciparum (52.3%), and the most frequent area of acquisition was Africa (54.2%), followed by Asia (20.9%) and Oceania (19.6%). The most common reason for travel among Japanese patients was business. A significant proportion (22.2%) of vivax malaria cases experienced relapse despite standard primaquine therapy. Most primaquine failures were from Oceania. We also found that a substantial number of Japanese patients contracted malaria without chemoprophylaxis and consulted medical facilities with an unfavorably long delay from initial symptoms (median: 3.0 days). Direct education of travelers and travel companies, in addition to health care providers, is likely necessary to improve outcomes of imported malaria.
authors.affiliation: Division of Infectious Diseases, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Miura
authors.forename: Mikio
authors.initials: M
authors.lastname: Kimura
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Koibuchi
authors.forename: Tokiomi
authors.initials: T
authors.lastname: Endo
authors.forename: Hitomi
authors.initials: H
authors.lastname: Nakamura
authors.forename: Takashi
authors.initials: T
authors.lastname: Odawara
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Wataya
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Nakamura
authors.forename: Aikichi
authors.initials: A
authors.lastname: Iwamoto
mesh_terms: D000328:Adult; D000349:Africa; D000962:Antimalarials / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008288:Malaria / Q000150:complications / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D044349:Oceania; D012008:Recurrence; D012189:Retrospective Studies; D013020:South America; D014195:Travel
chemical_list: D000962:Antimalarials