Malaysia is on heightened alert for bird flu in its northern regions after a probable case of human-to-human infection was detected in neighbouring Thailand, officials said today.

"We view this case seriously and our staff are intensifying swab-taking among fowl to ensure they are free of the avian flu," Idris Kadir, veterinary department director in the northeastern state of Kelantan, was quoted as saying by Bernama.

He said health officials have intensified house-to-house checks in the state, isolating villagers with flu-like symptoms, and the police and army are checking birds leaving that state.

Kelantan was placed under quarantine two weeks ago after the bird flu virus was found to have jumped outside a 10-kilometre quarantine zone around the first village hit by the H5N1 strain, which has killed at least 29 people in Vietnam and Thailand this year.

Poor compensation

Berita Harian newspaper said some villagers in Kelantan complained that compensation was too low, and had tried to hide their prized birds during culling operations.

Islamic clerics in the state have been urged to raise awareness by preaching on the danger of the disease, it said.

In Perlis, poultry farmers and traders have been told to apply for permits to transport their products and live birds in and out the state.

Officials say the disease was first brought into Malaysia by fighting cocks that had been exposed to the virus in Thailand and the new outbreaks were caused by the continued smuggling of chicken meat.

Thailand has announced a month-long "war" on bird flu as tests continued to discover if an outbreak within a Thai family threatened a global pandemic. Officials have said it appeared the strain had not mutated into a more infectious form for humans.

Malaysia's health ministry disease control director Ramlee Rahmat said migratory birds found dead recently on the disputed Spratly islands tested negative for bird flu. Five navy sailors feared to have contracted the disease from the dying birds have also been discharged.