Across Asia, people are closely following the global spread of swine flu from Mexico and preparing for the worst after the World Health Organisation raised its alert level for the outbreak.

Authorities in the region have boosted surveillance at airports and hospitals, stockpiled anti-viral drugs and other supplies to fight any outbreaks.

Face masks and anti-viral drugs like Relenza and Tamiflu flew off the shelves from pharmacies in some cities on Tuesday.

"It's really apparent, people have been buying face masks all day," said Cyrus Chan, the boss of a dispensary in Hong Kong's Wanchai bar district who had sold out his entire stock of 10,000 adult face-masks and only had child sizes left.

"Since SARS, this is the second time there's been such a great demand," Chan added, as a steady stream of customers asking for masks were told there wouldn't be any new stocks of adult masks till later.

Still, the mood on the streets appeared largely calm, with the world's most populous region, used to outbreaks of SARS and the H5N1 avian flu, not having yet reported any confirmed cases.

In South Korea, health authorities are testing a 51-year-old woman for suspected swine flu after a trip to Mexico.

"There hasn't been much of a reaction yet. I've just had a few calls asking if we have anti-viral drugs or special masks" said a pharmacist in downtown Seoul who asked not to be named.

"I guess South Koreans have grown accustomed to these breakouts over the past 10 years. But I will be bringing in more Tamiflu to the shelves."

... contd.