Hong Kong should stay vigilant in the atypical pneumonia battle even as the number of new infections is stabilising and showing a downward trend, Chief Executive Tung Chee Hwa said today.

He said concerted efforts from the community and medical staff as well as the Government's preventive measures had contributed to the progress.

However, he said this is a new virus and the overall situation still remains difficult.

"We must not take the disease lightly. We must not let up on our efforts," he said, adding that preventive measures in hospitals should be further improved to minimise the infection risk for medical staff.

While the Hospital Authority has taken management improvement measures, Mr Tung said he has asked the Secretary for Health, Welfare & Food Dr Yeoh Eng-kiong to take charge of the authority's operation.

He called on the public to pay special attention to the aged, as their resistance to disease is relatively weak, adding that the Government will ensure that preventive measures are taken, particularly in homes for the elderly.

Mr Tung also expressed concern about a secondary-three student who was suspected to have contracted atypical pneumonia.

"I have asked the Government departments, the school administrations, principals and teachers to be on maximum alert in order to ensure the safety of students," he said.

Turning to the upcoming Special ASEAN-China Leaders Meeting on the virus, he said Hong Kong being one of the worst hit places has a lot of valuable experience in the virus fight to share with participants.

"I also hope to be able to learn from the experience of other places in handling atypical pneumonia so that we can do even better," he added.