Asian governments have imposed strict controls to prevent swine flu from sweeping the region, screening air passengers and vowing to quarantine anyone showing symptoms of the deadly virus.
In New Zealand, where nine high school students and a teacher were thought likely to have swine flu after returning from Mexico, authorities were tracking down hundreds of air passengers who may also be at risk.
Health officials in Hong Kong, which was at the forefront of the SARS epidemic in 2003 and has since been on alert for bird flu, said they would detain anyone with symptoms of swine flu after arriving from an infected area.
Along with Singapore, Hong Kong advised against all non-essential travel to worst-hit Mexico, where more than 100 deaths were suspected, while China warned international travellers to be alert for any sign of infection.
Beijing also banned all pork imports from Mexico and parts of the United States, despite health officials saying the current outbreak was being spread by human-to-human contact.
The most common measure being put in place was the use of thermal scanners, which have been a common feature in many Asian airports since the Severe Acute Respiratory Syndrome (SARS) epidemic six years ago.
In Malaysia, Health Minister Liow Tiong Lai said that all travellers arriving from the United States -- where 20 cases have been confirmed in five states -- were being screened.
New Zealand Prime Minister John Key said the country was well prepared to deal with any new flu outbreak thanks to a plan drawn up during the 2003 bird flu scare, with stocks of anti-flu medication in place.
Japan said it would fast-track efforts to find a vaccine, while one company pulled back the families of staff based in Mexico, travel agencies scrapped package tours and drug stores reported a brisk trade in face masks.
Hong Kong announced some of the toughest measures to ward against an outbreak, warning that passengers arriving from affected areas and showing flu-like symptoms would be quarantined.
"We will take that patient to the hospital and let him stay there and have a test and until the test result is negative, we won't allow him to get out of the hospital," said Thomas Tsang, from the city's centre for health protection.
Airlines were broadcasting messages on selected inbound flights advising passengers to report symptoms such as sudden fever.
In Vietnam, where 56 people have died from bird flu since 2003, airport screening was focused on passengers arriving from North America, the Thanh Nien newspaper reported.
"The city must take immediate measures to prevent and cope with the dangerous disease," Nguyen Van Chau, the director of Ho Chi Minh City's health department, was quoted as saying.
Thailand, which recorded 17 fatal human cases of bird flu between 2004 and the last outbreak in August 2006, also started screening passengers arriving at its main international airport in Bangkok.
In Australia, hospital emergency wards, doctors and border control staff were given guidelines on how to spot the virus, as two people there were cleared of carrying the deadly strain.
Health Minister Nicola Roxon said that all planes arriving from the Americas would be required to report on the health status of passengers before receiving permission to land and that anyone with flu-like symptoms would be quarantined.
Despite the World Health organisation warning at the weekend that the virus had the potential to cause a pandemic, Taiwan Health Minister Yeh Chin-chuan urged the public to remain calm.
"There is no need to panic over the outbreak at the moment. The present situation is like a tropical storm emerging on the other side of the Pacific which poses no immediate threat to people here," he said.
Philippine authorities announced that they were screening passengers arriving from Los Angeles, San Francisco and New York and urged people to avoid hugging and kissing at public gatherings.