In July 2014, a Japanese traveller returning from Thailand was investigated for fever, headache, rash and conjunctivitis.
Zika virus RNA was detected in his urine sample by real-time reverse transcription polymerase chain reaction.
Serological tests showed cross reactivity of IgM against the dengue virus. Zika fever could be misdiagnosed or
missed and should be considered in febrile patients with a rash, especially those returning from Thailand.