Turkey and India have confirmed their first cases of H1N1 flu, all involving air passengers arriving from the United States.

Thirty-eight countries have now confirmed cases of the flu strain, a mix of swine, human and avian viruses, which last month prompted the World Heath Organization to raise its global pandemic alert level to 5 on a 6-point scale.

Turkey identified its first two cases in a family travelling to Iraq from the United States, health officials said on Saturday.

A 26-year-old American man, travelling via Amsterdam, was found to be suffering from the virus after arriving at Istanbul's Ataturk Airport en route to Iraq on Friday, Turkish Health Minister Recep Akdag said. Thermal cameras at the airport detected that he had a high fever.

Healthcare workers then determined his mother was also infected, Harun Celik, Health Ministry spokesman, told Reuters.

India's health ministry also confirmed its first case of the H1N1 flu on Saturday in an Indian man who had travelled from the United States, via Dubai, to the southern city of Hyderabad.

"He was identified at the screening at the airport and was quarantined, and his samples were drawn and they have tested positive," health official Vineet Choudhary, said.

Those close to him had been isolated and their health was being monitored, Choudhary said. His co-passengers on the flight to India were also being tracked down.

Japan precaution

The western Japanese city of Kobe said it would close some public schools for a week after eight people were confirmed as being infected with the new H1N1 influenza, commonly known as swine flu.

Three of the eight were teenage students from the same school -- the first confirmed cases in Japan involving people who had not been overseas. The other five were from another school, Kyodo news agency said.

The WHO, whose data lags national tallies, had earlier put the number of confirmed worldwide cases at 8,451, with 74 deaths.

The vast majority of deaths -- 68 -- have been in Mexico, where the outbreak started. The United States has reported five, and Canada and Costa Rica one each.