Health inspectors have yet to find the cause of the spread of bacteria that causes the potentially fatal legionnaire's disease. Traces of the bacteria have now been found in the office of the secretary for home affairs - the sixth minister's office affected. A sample taken from the private toilet of Tsang Tak-sing's office in the west wing contained legionella pneumophila. Nine other infection spots had been found earlier in the complex.

'We have observed that the contamination is usually found in places where there is warm water,' Chow said. 'We are not sure whether that is a crucial point. The bacteria was not found in the water tower. We are looking into the pipes for answers.'

Secretary for Development Carrie Lam Cheng Yuet-ngor said the pipes had been sterilised according to standard procedure after the building's construction Lam also reiterated a statement by architectural services director Leung Koon-kee that a test for the bacteria was not required under international standards.

'The Water Supplies Department advises people to use water supplies actively to avoid the accumulation of bacteria. If the water taps are not used frequently, the users or owners of the building should be responsible.'

Gammon-Hip Hing, the contractor for the site, said it followed standard procedures to cleanse the water tanks and pipes before handing over the building to the government.

Lawmaker Wong Kwok-hing demanded the government apologise for the scandal. But Chow said: 'We have been acting as quickly as we can to handle the situation. I believe it is now under our control.'

Wong disagreed, saying the incident showed the government had not conducted a proper inspection.

He suggested subjecting staff at the complex to body checks, especially those who were old and had underlying health problems.

Microbiology professor Ho Pak-leung described the incident as a serious matter as more dirty spots were discovered.

'All infected taps should not be used until further tests prove they are safe,' he said.

The bacteria has been found in the private toilets of six bureau chiefs, the toilet in the chief executive's office, a canteen within the headquarters, a canteen outside the east wing and the dining hall in the Legislative Council building.

The first place the bacteria was found was in the office of Secretary for Education Michael Suen Ming-yeung, who was diagnosed with legionnaire's disease two weeks ago.

Water supplies to the Legco building were suspended for 36 hours this week. The Legco commission said two tours of the Legco building had been staged since it opened, and participants had been required to wear face masks. A spokesman was unable to say whether any tours this week had been cancelled.

123

The number of legionnaire's disease cases caused by an infection at the Playboy Mansion's hot tub in Los Angeles last year