# 4083
Last Friday we learned of two hospitals – one in North Carolina,and one in Cardiff, Wales – that reported small clusters of Tamiflu resistant H1N1 infections among their patients.
Further investigation has turned up a 6th case in the Wales hospital, and there may yet be another.
While these reports are concerning, and of scientific interest, it is import to remember that for now Tamiflu remains effective in the overwhelming number of cases. And Relenza, another antiviral, is still effective when Tamiflu is not.
The number of resistant cases that have been reported is still very small. Given the heavy usage of Tamiflu, it would not be unexpected to see more resistant cases develop over time.
In just over a year seasonal H1N1 went from being more than 90% sensitive to oseltamivir (Tamiflu) to nearly 100% resistant. So we know the potential is there for seeing something like that happen with novel H1N1.
Which is why we watch developments such as these with interest, particularly when it involves the transmission of a resistant strain.
Antivirals were always viewed as a stop-gap measure during a pandemic. The best defense against a novel influenza strain is vaccination.
This report from the BBC.
New drug-resistant swine flu case
Page last updated at 11:55 GMT, Thursday, 26 November 2009
A sixth person has tested positive for a Tamiflu-resistant strain of swine flu, public health officials say.
The patient is linked to five people who last week became the world's first confirmed cases of person-to-person transmission of such as a strain.
Another person in direct contact with the group at University Hospital of Wales, Cardiff, has been tested.
Three patients remain in hospital, with one in critical care and the other two treated in isolation.
Public health officials said vaccinations remain the most effective way of combating swine flu.
Dr Roland Salmon, director of the National Public Health Service for Wales' Communicable Disease Surveillance Centre, said it was "not unexpected" that more patients on a unit treating people with severe underlying health conditions would test positive for the Tamiflu-resistant strain.
He said: "In this case, the resistant strain of swine flu does not appear to be any more severe than the swine flu virus that has been circulating since April.
