Tamiflu-resistant H1N1 viruses have not spread to hospital staff or beyond despite spreading among two clusters of patients in Britain and the United States the World Health Organization said.
Investigations to date showed that the resistant-form of swine flu was not transmitted outside of two hospital wards in Wales and North Carolina where they emerged in October and November, the WHO said in statement issued overnight.
A total of a dozen patients, all with severely suppressed immune systems due to underlying medical conditions, were infected with H1N1 viruses resistant to oseltamivir, the generic name for Roche's Tamiflu.
"Transmission of resistant virus from one patient to another is suspected in both outbreaks," the WHO said.
"No illness in staff caring for these patients has been detected, suggesting that the resistant virus does not spread easily to otherwise healthy people, especially when good measures for infection control are in place."
All 8 patients in Wales were hospitalized because of severe blood disorders, which severely weakened their immune systems, according to the United Nations agency. All are alive, including one being treated in intensive care...