A Japanese woman who arrived from the United States at Narita airport Monday and tested positive for the influenza A virus was confirmed not to be infected with the new strain of the flu virus as a result of further tests, the health ministry said Tuesday.
The woman in her 40s tested positive for the influenza A virus in a preliminary check conducted on the plane upon its arrival at the airport east of Tokyo. Further examinations at the National Institute of Infectious Disease confirmed that the virus she had was not that of the new H1N1 strain that is spreading worldwide. She had instead contracted Soviet A-type influenza, said the Ministry of Health, Labor and Welfare.
No cases of the new strain of flu have yet been confirmed in Japan, although there have been several cases in which patients tested positive for the influenza A virus which turned out to be that of a different strain.