Many tour companies abroad have cancelled trips to Phuket out of fear of Legionnaire's disease, officials said yesterday.

"Warnings have been sent to about 37 European countries that four foreign tourists came down with the disease after staying at a Phuket hotel," Deputy Governor Worapoj Rattasema said.

The Phuket Gazette said that Scandinavian papers were highlighting the case but whether the tourists were exposed to the disease at the hotel had not been confirmed.

People can catch Legionnaire's disease by breathing moist air from a water source contaminated with Legionella pneumophila, such as cooling towers used in industrial cooling water systems as well as in large central air conditioning systems, evaporative coolers, hot water systems and showers.

The disease may also be spread in a hot tub if the filtering system is defective. Freshwater ponds and creeks are other potential sources.

In its most common form, the symptoms appears between two and 10 days after exposure.

Phuket public health officials held the workshop to advise on how to prevent and control Legion-naire's disease and to encourage hotel operators and tour firms to follow the disease-prevention measures adopted in Europe.

Worapoj said European hotels would compensate its guests up to ¤21,000 (Bt100,000) if they contracted Legionnaire's disease from their premises. "It's better to take preventive measures," he said, adding that any outbreak would cripple the tourism industry here.

Dr Wiwat Sitamanoch of Phuket's public health office said Legionnaire's disease causes fever, headache, chills, chest pain and difficulty in breathing.

Local agencies have been implementing measures against Legionnaire's disease, he said.

Patong Hospital director Taweesak Netwong said operators should urgently restore public trust in order to attract tourists back.

Dr Thawat Suntrajarn, head of the Disease Control Department, said authorities had already ascertained that hotels in Phuket had proper water cooling systems.

"It's safe. Tourists, local and foreign, can be assured of the hygienic standard," he said.

All tourist destinations in the country were required to control the spread of Legionella pneumophila, he said.

"So far, Legionnaires' disease is not very threatening and can be cured easily. Besides, it's not a communicable disease," he said. The disease would claim lives only in its most serious form, he said.

No one has ever been reported of dying from Legionnaire's disease in Thailand, he added.