Wednesday, December 02, 2009

WHO Briefing Statement On Tamiflu Resistant Viruses

 


# 4013

 

Lisa Schnirring of CIDRAP News tonight has an excellent overview of a briefing statement and a press conference held today by the WHO (World Health Organization) regarding Tamiflu resistant viruses and the need to `tweak’ treatment regimens for immunocompromised patients.

 

I’ve got the opening to Lisa’s overview, followed by the briefing note posted on the WHO site.

 

WHO: Resistant flu clusters warrant greater vigilance, treatment tweaks

Lisa Schnirring * Staff Writer

Dec 2, 2009 (CIDRAP News) – The World Health Organization (WHO) said today that oseltamivir (Tamiflu)-resistant pandemic H1N1 cases in hospital settings suggest that treatment doses may need to be increased in immunocompromised patients who have flu symptoms.

 

The agency made this statement after a teleconference with experts about two recent clusters of resistant cases. It also concluded that the events don't signal a public health threat.

 

The WHO, in a statement, said emergence of drug-resistant flu in severely immunosuppressed or immunocompromised patients is expected and has been well documented in seasonal flu.

 

In late October a Welsh hospital detected an outbreak of oseltamivir-resistant pandemic H1N1 in eight patients who had severe hematologic disorders. Edwina Hart, health minister for the Welsh Assembly Government, said today in a statement that three of the patients appear to have been infected in the hospital.

 

Three are still hospitalized, one in critical care. All are responding to treatment with a different antiviral, she said.

 

Hart said so far there is no evidence that the resistant strain spread outside the hospital and that it does not appear to be any more severe than nonresistant strains.

(Continue . . . )

 

You’ll find more details on the North Carolina cases at Duke Hospital Reports No Further Spread Of Resistant Strain.

 

This is the WHO briefing note.  It is rather lengthy, so I’ve not posted the entire thing.

 

Follow the links to read it in its entirety.

 

 

Oseltamivir resistance in immunocompromised hospital patients

 

Pandemic (H1N1) 2009 briefing note 18

 

2 DECEMBER 2009 | GENEVA -- WHO has been informed of two recent clusters of patients infected with oseltamivir-resistant H1N1 viruses. Both clusters, detected in Wales, UK and North Carolina, USA, occurred in a single ward in a hospital, and both involved patients whose immune systems were severely compromised or suppressed. Transmission of resistant virus from one patient to another is suspected in both outbreaks.

 

The emergence of drug-resistant influenza viruses in severely immunosuppressed or immunocompromised patients undergoing antiviral treatment is not unexpected and has been well documented during seasonal influenza. Virus replication can persist in such patients for prolonged periods of time despite antiviral treatment, creating an environment in which drug-resistant viruses can readily be selected. This phenomenon has also been observed for the pandemic (H1N1) 2009.

 

Upon receipt of the reports, WHO organized a telephone conference with officials and staff from the hospitals and experts in clinical medicine, epidemiology, and virology to discuss the two outbreaks. Particular attention is being given to the best treatment options for immunocompromised patients who become infected with the pandemic virus.

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