A resident of a home for the disabled in Shau Kei Wan is the first local resident with human swine flu that is resistant to Tamiflu, a drug widely used to fight the disease. The case is just the seventh in the world, according to the Centre for Health Protection. The woman, 40, started taking the antiviral drug in the middle of last month after 21 people at the home for the physically and mentally disabled fell ill. She came down with a fever, cough and sore throat six days later and was sent to Pamela Youde Nethersole Eastern Hospital for treatment. She was confirmed to be infected with swine flu and has since recovered. Laboratory test results available yesterday showed she was the only one of the 21 infected people from the home to be resistant to Tamiflu. The Centre for Health Protection called for calm and said there was no sign of Tamiflu-resistant cases spreading in the community. The centre regards this as the first local case because the patient has not been out of Hong Kong. Last month the authorities reported that a 16-year-old Hong Kong girl had contracted a strain of swine flu resistant to Tamiflu. She had flown from San Francisco in mid-June. She did not take any antiviral drugs, but laboratory tests determined that the strain was resistant to Tamiflu. The centre's controller, Thomas Tsang Ho-fai, said it would monitor the situation closely to see whether the use of Tamiflu needed to be reviewed to prevent the virus developing resistance. 'But there is no sign of a Tamiflu-resistant strain of H1N1 spreading. So far, it is still an effective drug to treat H1N1,' Dr Tsang said. Tamiflu has been used worldwide to treat human swine flu. Meanwhile, the Department of Health said another 224 patients had been confirmed with swine flu, taking the number of cases the city has seen to 6,640. Of the newly infected, 121 are males and 103 females; the youngest is two months old and the oldest 73. Among them are eight public hospital staff, and a lifeguard working at Hap Mun Bay Beach in Sai Kung who has been on sick leave since Wednesday. Forty-eight swine flu patients are being treated in public city hospitals. Five of them are in critical condition, four serious, and the rest in stable condition. Two of the five critical cases were confirmed yesterday. One was a 60-year-old man who was admitted to United Christian Hospital on Thursday. The other was a 63-year-old woman who was admitted to North District Hospital, also on Thursday, after developing flu symptoms a week ago.