The dark shadow cast by the Sars epidemic in 2003 was behind the government's decision to close all primary and special schools, nurseries and kindergartens, according to a government source.
While the government knew the drastic action taken late on Wednesday would leave it open to criticism and cause inconvenience to pupils and parents, the potential ramifications of delaying the decision were deemed to be much worse.
'The shadow left by Sars is still fresh,' the source said. 'So we decided, 'why don't we take a more cautious and immediate approach by shutting down the classes if we find the virus has more serious effects on children than on adults?''
Senior government figures also realised public reaction would be more severe if there was evidence to support an immediate suspension, but the decision was not taken.
Another source said: 'What we are talking about is government face and children's lives, and what was more important was obvious to the government.'
In 2003, the government was accused of underestimating the seriousness of the outbreak of severe acute respiratory syndrome, which spread quickly through the community, leaving 299 dead and eventually forcing health chief Yeoh Eng-kiong to resign.
Secretary for Food and Health York Chow Yat-ngok said that Chief Executive Donald Tsang Yam-kuen and Chief Secretary Henry Tang Ying-yen were fully behind the decision to close the schools.
Sources said Dr Chow sought the support of Mr Tsang and Mr Tang at about 9pm on Wednesday, shortly after an expert committee set up to investigate recent deaths suggested a suspension. The decision was announced shortly before 10.30pm.
Dr Chow apologised to those affected. 'It is a difficult decision which put huge political pressure on me,' he said.
The health chief said if the decision had been delayed for a day, more chaos would have ensued. But he added that there was not enough evidence to suggest there had been a mutation of the influenza virus.
A government official said the political pressure the administration was talking about was criticism that the government had overreacted and not given sufficient notice.
The government admitted there was no good time to announce the closure as the move would draw attention from the release of the public consultation paper on health reform.
Dr Chow said: 'I had considered postponing the [health reform] publication [on Wednesday] night in view of the flu outbreak. But we have discussed the issue for a long time. Legco members have demanded an early release of the consultation document. It has not distracted our attention from the outbreak.
'I have spent most of my time on the flu issue in the past few days ... I don't think there has been any conflict. It's not the best time [to publish the document], but it's not easy to find an alternative timing.'