The man in charge of defending Hong Kong against the threat of deadly epidemics has resigned, causing shock and regret in the medical world.
Dr Thomas Tsang Ho-fai, 46, has been head of the Centre for Health Protection since 2009 but was already well known for his star role during the severe acute respiratory syndrome pandemic in 2003.
He was nicknamed "Superdetective Fai" for his exhaustive efforts tracking the source of infection, leading his team to the Metropole Hotel in Kowloon following the trail of a patient who unwittingly helped spread the deadly virus worldwide. It killed 299 people in Hong Kong.
Before that he took a lead role in the battle to contain an outbreak of bird flu in 1997. In the year he became controller of the Centre for Health Protection he had to take on flu - and his image as "the flu fighter" grew.
A senior private doctor who asked not to be named said: "His performance was outstanding, especially remarkable during the swine flu pandemic … It will be a great loss for the public."
The announcement that Tsang was quitting was made by the Secretary for Food and Health, Dr Ko Wing-man. He said Tsang handed in his resignation late last month and would leave his post at the end of this year.
The government would try to recruit his replacement from within the city. "I am very sorry to see him leave. I have tried to persuade him to stay, but I respect his decision," Ko said.
He said Tsang had resigned for personal reasons and had told him he planned to take a rest before considering his next move.
Tsang was believed to be unhappy when Dr Constance Chan Hon-yee, then head of the Centre for Food Safety, was named to replace Dr Lam Ping-yan as the director of health. Both Tsang and Lam's deputy, Dr Gloria Tam Lai-fan, were felt to have missed out on the promotion.