The Health, Labor and Welfare Ministry said Thursday that an Okinawa woman who was suspected of having contracted the West Nile virus during her trip to the United States has tested negative.
The ministry said the final tests have been conducted on the 42-year-old woman by the National Institute of Infectious Diseases in Tokyo. The tests started on Aug. 19.
According to the ministry, the woman has gone back home and is recovering.
Alarmed by a widespread West Nile outbreak in the United States and Canada, the ministry decided last month to extend a ban on blood donations from those returning from abroad as part of efforts to contain the virus.
The virus, transmitted to humans by mosquitoes, is commonly found in Africa, West Asia and the Middle East. There is no vaccine.