The Department of Health has detected a strain of human swine flu virus resistant to Tamiflu. Similar cases have been reported in Denmark and Japan.

The virus was identified during routine sensitivity tests. It is the only Tamiflu-resistant strain so far among 200 samples tested, however, it is sensitive to Relenza. Further tests are underway.

Hong Kong has maintained an antiviral stockpile of both Tamiflu and Relenza.

The strain was isolated from a 16-year-old girl who arrived from San Francisco. She was stopped at the airport on June 11. She was isolated at Queen Mary Hospital with mild symptoms and discharged June 18.

The department will report the case to the World Health Organisation and closely liaise with global health authorities to monitor developments in the virus.

Up to 2.30pm today, the department reported 44 newly confirmed swine flu cases, bringing the total tally to 901. Of the new cases, 26 were men and 18 were women, aged two to 81. One of them involved a United Christian Hospital female shroff clerk who travelled to Thailand June 24 to 28.