HONG KONG, March 16: Global health authorities were on the alert on Sunday for a severe type of pneumonia that has killed at least nine people, infected more than 100 and sparked a warning from the World Health Organisation (WHO).

The spread of the disease has alarmed travellers. In Hong Kong’s international airport, many people arriving from Taiwan, Singapore and elsewhere were wearing surgical masks.

“There’s nothing we can do about it, so we have to take precautions,” one visitor told Hong Kong’s Cable TV.

Cathay Pacific airline said it had ordered staff not to check in passengers showing symptoms of illness and to refer them for medical assessment.

A spokesman for the Geneva-based WHO said there were reports two people from the same family had died in Canada, taking the death toll to nine worldwide since the first outbreak of Severe Acute Respiratory Syndrome (SARS), an atypical pneumonia whose cause is not yet known, was detected in China in February.

The disease infected four other members of the Canadian family, and on Saturday a woman who had been in close contact with them fell sick with the symptoms, Canadian health authorities said on Sunday.

“This syndrome, SARS, is now a worldwide health threat,” WHO director-general Gro Harlem Brundtland said in a statement.

The illness, which starts with flu-like symptoms such as coughing, high fever and shortness of breath, can deteriorate rapidly into pneumonia.

Dozens of people in Hong Kong and Vietnam, many of them hospital staff, are also infected and numbers have been rising steadily in Singapore and Taiwan.

US health officials said on Saturday they were investigating reports that two people passing through Atlanta and New York had the illness. They gave no other details.

Six more infections were reported in Hong Kong and Singapore on Sunday. WHO said it had also received reports of cases in Indonesia and Thailand, but it gave no details.

In southern China, 305 people contracted severe pneumonia in February and five died. WHO and other experts are studying if there are links between these cases and others elsewhere.

ADVISORY: Cathay said one of its passengers had respiratory problems during a flight from Hong Kong to Vancouver on March 6. It was checking if any of its staff had come into contact with the man.