Medical experts in Hong Kong have been unable to identify a respiratory illness affecting children. Doctors at the Caritas Medical Center in Kowloon said two of 30 admitted patients showed signs of respiratory tract infection, whilst another six were suffering from fever.

"Infection-control measures have been stepped up at the hospital and medical staff at laboratories in the Center for Health Protection, local universities and the Department of Health are conducting tests to identify the source of the virus," said Hospital Authority Chief Executive William Ho, who visited the patients on Tuesday.

Secretary for Health, Welfare and Food York Chow Yat-ngok refused to say if the mystery illness was a new virus.

He said it "could be related" to an existing disease that is prone to attacking children and patients with weaker immunity.

Health officials placed a green code warning around the hospital in the Sham Shui Po district and isolated the affected ward.

The hospital has also closed its pediatric wards to new admissions, and visitors are required to wear protective gear and subject to other restrictions.

The health chief urged citizens to be vigilant about their health during the peak flu season, adding that students with respiratory illnesses or fever should not go to school.

Meanwhile, consultant doctor at the Center for Health Protection Thomas Tsang Ho-fai, revealed on a local radio program that two people who had been in touch with infected children had also shown symptoms of fever.

However, Ho said they had recovered quickly, indicating that the virus was "not very strong."

"Results of gene and virus tests will be available in about one or two days," he said.

Ho also told local radio that he did not rule out the possibility of some more cases in the coming days, but said the peak period of the infection had passed.

(China Daily November 17, 2004)