Two Japanese schoolgirls who have caught swine flu had attended a mock conference in New York reportedly joined by 2,300 students from around the world, officials said Thursday.
The girls, both aged 16, tested positive for the A(H1N1) virus Wednesday, becoming the first known cases in the greater Tokyo area, officials said.
They were diagnosed after returning Tuesday from a week-long visit to New York where they took part in what Japanese media described as a United Nations-style conference with 2,300 international students held May 14-16.
The World Federation of United Nations Associations on its website listed the 10th annual Model UN conference in New York for those dates, where over 2,300 students were invited to discuss a variety of international issues.
Pupils from five other Japanese schools also attended the event, but officials said none of them have been reported to be sick.
One of the infected girls lives in Hachioji, western Tokyo, and the other in Kawasaki City, just south of the capital. They attend the same school in Kawasaki.
The number of confirmed swine flu cases in Japan had reached 276 by noon Thursday, according to the health ministry. There have been no fatalities from the virus in Japan and most cases have been mild.