AUSTRALIANS travelling overseas have been warned they may be prevented from returning home if they started to show symptoms of the pneumonia-like illness SARS (Severe Acute Respiratory Syndrome).

Australia's Chief Medical Officer Richard Smallwood said that overnight the World Health Organisation (WHO) had recommended excluding air passengers showing signs of the illness from travelling.

"This includes screening measures that could see people with fever or other flu-like symptoms being excluded from further travel," Prof Smallwood said in a statement.

The measures, recommended by WHO for consideration by national health officials and airport authorities, would involve an interview with passengers to detect whether or not they were showing symptoms.

Professor Smallwood said Australians who were concerned about the risk of SARS should reconsider their need to travel or to transit through Hong Kong, Singapore, China, Vietnam and Canada.

To date, no cases of SARS had been found in Australia, although two new people were now under investigation in NSW, Prof Smallwood said.

Worldwide, the SARS outbreak had claimed 53 lives and made 1,408 people ill, WHO said overnight.

The Commonwealth Department of Health and Ageing said members of the public could call a national phone information line with any enquires.

The phone line, 1800 004 599, will be staffed seven days a week from 9am to 8pm (AEST).

AAP