The controversial policy under which nearly 300 guests and staff at a hotel where Hong Kong's first - and so far, only - swine flu patient stayed were quarantined would be modified, the health minister said yesterday. But York Chow Yat-ngok said the government still thought it had been right to impose the seven-day quarantine, which ends tomorrow. The government is preparing to get tough with six guests of the hotel, the Metropark in Wan Chai, who were not there when the quarantine was imposed and who have since failed to come forward despite calls from officials to do so. They will be stopped at the border if they try to leave Hong Kong and may face legal action. Under the Prevention and Control of Disease Ordinance, anyone who escapes from detention for outbreak control is subject to arrest and imprisonment for six months. The hotel was quarantined on Friday after a 25-year-old Mexican tested positive for the new swine flu virus which first emerged in his country. The move angered guests and staff. The Mexican fell ill after arriving on a flight from Shanghai last Thursday and checking in to the Metropark. He remains in Princess Margaret Hospital. Four quarantined compatriots, and other Mexicans from the mainland and Hong Kong, flew home early yesterday. The new flu strain - which worries doctors because it mixes human and bird flu with swine flu viruses from three continents - continues to spread. A second death from the flu in the United States, and the first of a US citizen, was reported yesterday. Forty-two Mexicans have died. Dr Chow, the secretary for food and health, said that as more information about the new virus emerged, the government was reviewing its quarantine policy. A 'modified' policy could be ready in a week. Dr Chow said he had an understanding with World Health Organisation director general Margaret Chan Fung Fu-chun that it would not stop Hong Kong taking stringent measures to stop swine flu. 'The decision [to quarantine the hotel] was made to protect public safety. 'Isolating a patient early is the rule of thumb in outbreak control, although some places may not be able to do so,' he said. 'Given the background of the Sars outbreak in 2003 and the huge investment in our health care system, Hong Kong is confident in doing so.' University of Hong Kong microbiologist Ho Pak-leung said he would support quarantining a hotel if another traveller brought the virus to Hong Kong. 'The government is obviously under political pressure to review its quarantine measures [but] this stringent measure is needed to control an outbreak,' he said.