03:19 PM PDT on Friday, August 14, 2009
SEATTLE – The health department says two immunosuppressed patients being treated for swine flu in King County have been identified as resistant to Tamiflu, an antiviral treatment.
The patients include a male teenager and a female in her 40s who have no links to each other.
The health department says both patients had compromised immune systems, which has been shown to raise the risk for prolonged infection and development of antiviral resistance.
One patient has recovered and the other is being treated with a different antiviral medication.
Health officials say there is no evidence indicating that people who came in contact with the two patients became infected with a Tamiflu-resistant virus.
Officials say Tamiflu resistance remains rare. As of Aug. 11, health officials have identified a total of 11 novel H1N1 flu viruses that are resistant to Tamiflu worldwide.
"Viruses can develop drug resistance over time. It's important that antiviral treatments only be used as recommended by a health care provider, to minimize drug resistance and preserve an important tool against the illness for those who need it," said Dr. David Fleming, Director and Health Officer for Public Health - Seattle & King County. "The vast majority of people with H1N1 virus continue to be treatable with Tamiflu, and in cases where it becomes ineffective, other options are available."