Uk investigates spread of drug resistant swine flu

British health officials are investigating the likely person-to-person spread of a drug-resistant strain of swine flu, the Health Protection Agency has said.

There have been nine confirmed cases of an H1N1 variant among patients on a ward in a hospital in Wales, it said, five of which are known to be resistant to oseltamivir – the generic name of Roche AG's antiviral drug Tamiflu.

The cases occurred in people with a serious underlying health condition that is known to cause Tamiflu resistance in flu cases, the HPA added.

"Although further epidemiological investigation is under way, it would seem likely that transmission of oseltamivir-resistant H1N1 virus has taken place," it said in a statement.

The HPA said the swine flu variant remained sensitive to alternative antiviral drug Relenza, made by GlaxoSmithKline, and that patients were responding well to it.

"At present we believe the risk to the general healthy population is low," it said.

The World Health Organisation has reported 57 cases of Tamiflu resistance worldwide. There have not yet been any confirmed cases of person-to-person transmission, although a possible case in the United States is under investigation.

The British government launched a national pandemic flu service in July to allow people to get a diagnosis and prescription online or over the phone without visiting a doctor.

It said on Friday it was taking the development of a Tamiflu-resistant strain seriously but it would continue to offer the antiviral to all patients.

"Our strategy to offer anti-virals to all patients with swine flu is the right one, to help prevent complications and reduce the severity of the illness," the Department of Health said in a statement.

The H1N1 virus has so far killed 214 people in the United Kingdom.

A nationwide vaccination programme began last month, initially targeting those considered high risk, such as pregnant women and front-line healthcare workers.

Norwegian health authorities have discovered a potentially significant mutation of H1N1 that they said could be responsible for causing the most severe symptoms among those infected but that they do not believe has any implication for the effect of flu vaccines or antiviral drugs.

- Reuters