WHO investigates Tamiflu resistance, updates antiviral recommendations for H1N1 patients with severely compromised immune systems

Following recent reports of clusters of Tamiflu resistance, the WHO on Wednesday recommended that patients with severely weakened immune systems who become infected with the H1N1 (swine flu) virus receive additional antiviral treatment as needed throughout the duration of their illness, Agence France-Presse reports. "Although the WHO said there was no evidence that the two clusters found in Wales and in North Carolina [U.S.] marked a wider public health threat, it reiterated calls for vigilance and modified treatment advice for the frontline flu drug," the news service writes.

In addition to ramping up antiviral treatment, the agency advised physicians treating patients with suppressed immune systems who are not responding to Tamiflu be given the alternative antiviral, Relenza (12/2).

Also on Wednesday, the WHO announced an investigation into the Tamiflu-resistant cases of H1N1 in hospitals in Wales and the U.S. showed the virus had not spread among hospital workers and the community, the Canadian Press reports. "'We're confident in saying that at the moment it looks to be limited, but ... it's a question of continually monitoring,' said Charles Penn, an antiviral expert with the WHO's global influenza program.

The agency said in a statement that though the investigation is still underway, early results suggest the resistant viruses don't spread easily to healthy people, especially those following proper infection control procedures," the news service reports (Branswell, 12/2).