HERE is what will happen if you land at Changi Airport and have been in Mexico in the past week: You will have to fill in a form declaring that you were there.

After that, you will have to stay at home for seven days under a Home Quarantine Order which is backed by law.

Those who are visiting Singapore but have also set foot in the epicentre of the swine flu epidemic will be put up in chalets, hotels or flats.

No, it does not matter if the returning traveller or tourist is feeling perfectly fine.

This 'interventionist' approach is needed as the virus can slip past thermal screening at border checkpoints as symptoms may not have shown up yet in its victims.

Health Minister Khaw Boon Wan said that other affected areas might be placed on the list later on, but a start will be made with Mexico.

As during the Sars crisis, those quarantined will get calls to check if they have developed symptoms. If so, an ambulance will take them to the Communicable Disease Centre for a thorough assessment. Under the Infectious Diseases Act, those who contravene the order can face a fine of up to $10,000 and up to six months in jail.

Six undergraduates from Nanyang Technological University (NTU) are expected home in the next few days from an exchange programme in Mexico.

Given the orange alert, an NTU spokesman said: 'The university is instructing these students to return to Singapore. NTU officers will be in touch with them daily to check on their well-being during their quarantine period.'

Mr Khaw acknowledged that the process of self-declaration would require honesty on the part of travellers. But he added that immigration officers are also pretty good at checking 'chops' on passports for those coming off long-haul flights.

Read the full story in The Straits Times today.