Japan confirmed its first case of the new H1N1 flu in its densely populated capital Tokyo on Wednesday, as the number of cases rose to more than 250 in the western part of the country. Nobody has died of the virus in Japan and the majority of cases, affecting mostly teenagers, have been mild, a Health Ministry spokesman said,

H1N1 In Tokyo

The World Health Organisation, which has been watching the situation in Japan closely, said on Wednesday that the H1N1 strain has killed 80 and has been confirmed in over 10,000 cases globally.

In Tokyo, a 16-year-old female high school student, who had recently returned from New York, tested positive for the new flu strain, a Tokyo metropolitan government official said.

About 4,500 schools, mostly in the western prefectures of Osaka and Hyogo about 400 km (250 miles) from Tokyo, have closed their doors until the end of the week. The local government in neighbouring Shiga prefecture, which also confirmed its first case on Wednesday, was also urging its schools to follow suit.

A university campus in Shiga was also closed, affecting 18,000 students, after one of them was infected with the virus.

A hospital in the port city of Kobe, where a member of staff had been infected, was to ban visits to flu patients, Kyodo news agency said.

Japanese Health Minister Yoichi Masuzoe told a news conference on Wednesday that a study on 43 cases in Kobe city in Hyogo prefecture suggested the new flu strain was behaving similarly to the seasonal flu and that not everyone with the new flu needed to be hospitalised.

The government is considering drawing up a new plan by Friday to deal with the virus, which is not as deadly as the avian influenza for which existing plans had been created.

It is also considering winding down strict health checks at international airports at the end of the week, which had been imposed to try to buy time before an outbreak in Japan.

Many passengers on public transport in urban areas have been wearing surgical masks in an effort to avoid infection, and domestic media said stocks of masks were running short.

The vast majority of H1N1 cases are in Mexico and the United States, but the spread of the disease to about 40 countries led the World Health Organisation to declare a pandemic was imminent at the end of April.

Its pandemic alert level is now 5 on a 6-level scale.