A report of two cases of bird flu which proved resistant to treatment with Tamiflu have been reported in the New England Journal of Medicine.

Researchers from Oxford University said that two of eight Vietnamese patients with bird flu treated with Tamiflu (oseltamivir) had died, with evidence the virus had developed resistance to the drug.

The news will cause alarm around the world, as Roche's Tamiflu is being stockpiled as the frontline defence in the event of a global bird flu pandemic.

Lead researcher Jeremy Farrar described the findings as very worrying but said it had not come as a surprise, as drug resistance is a common problem in viruses, bacteria and parasites.

He told the BBC: "If this virus was to develop drug resistance and the ability to go from one person to another that would clearly be a major problem."

Dr Farrar added, however, that there was some evidence to suggest drug resistant viruses were less likely to jump from human to human but stressed the need for selective use of Tamiflu to minimise the problem of resistance.

Four of the other six patients infected who received Tamiflu treatment survived, their viral loads declining rapidly to undetectable levels.

The researchers suggest additional antiviral agents should be used alongside Tamiflu. In the UK, the Department of Health has confirmed it is looking at GSK's similar product Relenza as a back-up to Tamiflu.

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Friday , November 25, 2005

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