# 4053
I can remember when Friday’s used to be quiet on the flu front.
Those days are gone, apparently.
In a statement from the National Public Health Service for Wales, we get word of the likely (limited) spread of a Tamiflu resistant strain of the H1N1 virus at the University Hospital in Cardiff.
Oseltamivir Resistance is generally caused by a mutation, known as H274Y, where a single amino acid substitution (histidine (H) to tyrosine (Y)) occurs at the neuraminidase position 274.
Thus far, we’ve only seen scattered reports of Tamiflu resistance around the world, but it is likely that we are missing some cases. The vast majority of H1N1 flu cases continue to respond well to the drug.
Of the nearly 60 known resistant samples detected till now, most were so-called `spontaneous mutations’ that occurred in patients taking the antiviral.
In other words, they were not believed to have involved the transmission of a mutated virus.
Even if transmission is established in this case it appears to have been limited to a handful of immunosuppressed patients, and for now remains more an object of scientific curiosity than a public health concern.
A big hat tip and thank you to LIsa at CIDRAP for passing this link on. They will no doubt have some coverage of this story tonight on the CIDRAP website.
News: Person to person spread of swine flu resistant to Tamiflu
20 November 2009
The National Public Health Service for Wales (NPHS) has found person-to-person spread of a strain of swine flu resistant to Tamiflu within a South Wales hospital.
Five patients on a unit treating patients with severe underlying health conditions at the University Hospital of Wales, Cardiff, have been diagnosed with swine flu resistant to Oseltamivir (Tamiflu).
Three appear to have acquired the infection in hospital.
Dr Roland Salmon, Director of the NPHS Communicable Disease Surveillance Centre, said: “The emergence of influenza A viruses that are resistant to Tamiflu is not unexpected in patients with serious underlying conditions and suppressed immune systems, who still test positive for the virus despite treatment.
“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.
“For the vast majority of people, Tamiflu has proved effective in reducing the severity of illness. Vaccination remains the most effective tool we have in preventing swine flu so I urge people identified as being at risk to look out for their invitation to be vaccinated by their GP surgery.”
Chief Medical Officer, Dr Tony Jewell, said: “We know that people with suppressed immune systems are more susceptible to the swine flu virus, which is why they are a priority group under the first phase of the vaccination programme in Wales which is progressing at pace.
“We have stringent processes in place for monitoring for antiviral resistance in the UK so that we can spot resistance early and the causes can be investigated and the cases managed. Identifying these cases shows that our systems are working so patients should be reassured.
“Treatment with Tamiflu is still appropriate for swine flu and people should continue to take Tamiflu when they are prescribed it.
“It’s also important that good hygiene practices are followed to further prevent the spread of the virus.”
All patients diagnosed with Tamiflu-resistant swine flu on the unit have been treated with an alternative antiviral.
All other patients on the unit have been tested for swine flu.
Patients have been isolated or are being cared for in a designated area for influenza cases and Cardiff and Vale University Health Board has ensured that all appropriate infection control measures are in place on the unit.
Patients and staff at the unit have been offered swine flu vaccination. Patients due to come into the unit for treatment are being advised to have the vaccination from their GP in advance of coming to the hospital.
Household contacts of the patients with swine flu are being followed up to ensure early and appropriate treatment is offered should symptoms of influenza develop.
Two patients with Tamiflu-resistant swine flu have recovered and have been discharged from hospital. One patient remains in critical care and two others continue to be treated on the ward.
