ATLANTA — U.S. health officials are stepping up testing of swine-flu cases for Tamiflu resistance now that an American has come down with a resistant strain.
A California teen was diagnosed with swine flu last month after arriving in Hong Kong on June 11 and has since recovered.
The 16-year-old is a San Francisco resident and likely was infected in the United States, health officials said Tuesday.
Her illness was mild but noteworthy. She’s just the third person in the world to be diagnosed with a strain resistant to Tamiflu, the primary pharmaceutical weapon against the new virus.
The other two patients with resistant cases — in Denmark and Japan — had been taking Tamiflu as a preventive measure after coming into contact with someone with swine flu. The California girl had not taken Tamiflu, meaning she apparently was infected by an already-circulating resistant strain before she traveled to Hong Kong.
“It’s a little more concerning” than the previous cases, said Dr. Tim Uyeki of the federal Centers for Disease Control and Prevention.
Hong Kong health officials, known as aggressive in trying to find and isolate swine- flu cases, detected the resistant strain in the girl. Until an effective vaccine is developed, the drugs Tamiflu and Relenza are considered the best defense against the virus.
