Two in King County found to have been infected with Swine flu virus resistant to flu drug Tamiflu

Two patients in King County with H1N1 “Swine” flu have been found to have been infected with a strain of the virus that is resistant to the flu drug Tamiflu.

Tamiflu, whose chemical name is oseltamivir, is one of the two drugs recommended for the treatment of H1N1 infections.

The other drug, zanamivir, is marketed under the name Relenza.

Both patients, a male teen and a woman in her 40s, had compromised immune systems.

An compromised immune system can take longer to clear an influenza infection, and it is known that the longer an infection lasts, the more likely it is that a drug-resistant virus can develop during treatment, health officials said.

“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,” Fleming added.

One patient has recovered. The other continues to have symptoms and is being treated with zanamivir.

As of August 11, total of 11 novel H1N1 influenza viruses that are resistant to Tamiflu have been reported worldwide.

Health officials said that none of the health workers or other close contacts with these two cases became infected with the Tamiflu-resistant strain and that the risk of infection to the general population was “very low.”

Nevertheless, as a precaution, health officials here will intensify their monitoring here to detect any other cases of drug-resistant viruses in the community.

To learn more:

• Visit Public Health – Seattle & King County’s H1N1 information page.

Other Resources:

Swine Flu and You
http://www.cdc.gov/swineflu/swineflu_you.htm (English)
http://www.cdc.gov/swineflu/espanol/influenza_porcina_usted.htm (Espanol)

Facts about Swine Flu
http://www.cdc.gov/swineflu/key_facts.htm (English)
http://www.cdc.gov/swineflu/espanol/swine_espanol.htm (Espanol)

Preventing the Flu
http://www.cdc.gov/flu/protect/habits.htm?s_cid=swineFlu_outbreak_internal_003 (English)
http://www.cdc.gov/flu/protect/espanol/habits.htm (Espanol)

Latest news from CDC
http://www.cdc.gov/swineflu/ (English)
http://www.cdc.gov/swineflu/espanol/ (Espanol)

Symptoms and precautions from the Washington State Department of Health
English (PDF)
Spanish (PDF)
Chinese (PDF)
Korean (PDF)
Russian (PDF)
Vietnamese (PDF)
Large type (PDF)

Questions about swine flu?
Call King County’s Swine Flu Hotline
877-903-KING (5464)

Tags: 2009/H1N1, A/H1N1, CDC, Drug-Resistance, Flu, H1N1, Influenza, Influenza A, King County, Seattle, Swine Flu, Tamiflu, Washington

Category: Drugs & Medicines, Influenza