Updated at 12:50, May 7
A man in his 40s from Nagoya emerged Wednesday as having been possibly infected with a new strain of influenza that is feared to be developing into a global pandemic. However, early Thursday morning it was reported that he was not infected with the H1N1 virus subtype.
The Health, Labor and Welfare Ministry said the man tested positive for influenza A in a preliminary test after having a fever while staying in Tokyo. A second test conducted by a Tokyo health institution confirmed that he has been infected with Soviet A-type flu, the Tokyo government said.
Tokushima Prefecture said the results of a second test on a woman who arrived Monday at Kansai airport after a trip to the United States showed that she was not infected with any influenza virus.
Meanwhile, the health ministry said five other people suspected of being infected with influenza A (H1N1) upon arrival in Japan from the United States or Mexico have been confirmed as not infected with the new flu.
The five are a 14-year-old girl from Aichi Prefecture, an elementary schoolgirl from Kyoto City, a woman in her 30s and her child who live in Chicago and are currently staying in Gunma Prefecture, and a girl from Kyoto Prefecture.
They were either found to be infected with type-A Hong Kong flu, group A hemolytic streptococcus or not infected with any influenza virus, according to the ministry.
No cases of the new flu have been confirmed in Japan, although there have been several cases in which patients tested positive for the influenza A virus but the strain was not the same as the new flu.