BANGKOK - THAI Prime Minister Abhisit Vejjajiva on Sunday urged the country not to panic about H1N1 flu, after the number of cases grew ninefold in four days and a cluster emerged in a key tourist hub.

Health authorities reported that confirmed cases of the A(H1N1) virus soared to 150 on Sunday, compared with just 16 on Wednesday, including a number of foreigners.

Officials last week said 21 of the new infections were found among nightclub workers in the coastal city of Pattaya, who were tested after two Taiwanese tourists said on returning home they had contracted the disease there.

A Hong Kong visitor may also have contracted the virus on the southern resort island of Phuket.

'People should not panic. The death ratio for the new flu is probably lower than normal flu,' Mr Abhisit said in his weekly television programme.

He said the government was taking extra measures whenever cases were reported to confine the disease.

The public health ministry on Sunday advised people to wear masks if they are suffering from fever.

The government has begun a mass disinfection programme in hundreds of Bangkok's schools, while two private schools near each other in the capital were closed for a week after a student at one of them contracted the virus.

Thailand had its first reported case of swine flu on May 12 and its first domestic case in early June but there have been no fatalities.

The World Health Organisation raised its global alert to a maximum six on Thursday, saying swine flu had reached pandemic status because of its geographical spread. -- AFP