MANILA, Philippines - Even "American Idols" are not exempt from swine flu checks.

Philippine health authorities had to chase down David Cook and David Archuleta, the winner and the runner-up of last season's TV singing contest, to have them fill out a health checklist and report their temperatures at least twice a day before their open-air concert Saturday.

Edgardo Sabitsana, director of the quarantine bureau, said the celebrities rushed through the airport Wednesday without completing health checks that are mandatory for everyone entering the country.

Officials caught up with them in their hotel rooms Thursday and reminded them that they can be arrested if they do not co-operate, Sabitsana said.

"We had to mention the authority of the quarantine bureau ... that we can do something if they refuse," he said.

The singers were "very receptive, they were very co-operative," Sabitsana said.

He said they were briefed about keeping a distance of about two metres from other people, what to do if they exhibit flu-like symptoms, urged to use hand sanitizers and other "little things that their handlers may forget."

The Philippines has reported no case of swine flu, but authorities are taking no chances, especially with celebrities in contact with large numbers of fans.