More than 500 people were diagnosed with swine flu by Irish GPs last week, more than twice the number of cases to date confirmed by laboratory tests, the Department of Health has revealed.
The Department and the Health Service Executive also confirmed today that two people are now critically ill in hospital with the H1N1 virus.
Some 226 cases of the virus have been so far confirmed by laboratory testing. However this no longer reflected the number of people who had contracted swine flu, Dr Tony Holohan, chief medical officer with the department of health said.
"The number of laboratory confirmed cases has ceased to be a meaningful measure of the burden of the infection in the population," he said.
It was no longer practical to test everyone who presented to their GPs with symptoms of the virus, Dr Holohan said, and the HSE had moved to a policy of calculating numbers of cases through GP diagnosis, instead of laboratory testing.
The number of cases would be calculated weekly using a sample of 50 GP practices. In the week up to Sunday last more than 500 cases were diagnosed.
Some 12 people have been hospitalised with the illness so far and two of them have required treatment in intensive care, Dr Holohan said.
St James's Hospital in Dublin has said a man in his 30s from Slovakia was admitted last week and was critically ill with the virus.
Dr Holohan would not confirm if this man was one of the two patients admitted to intensive care. He said he was not prepared to give any details of any cases and would not confirm if either of the two critically ill patients had underlying illnesses.
The HSE has also issued a direction to GPs not to administer Tamiflu as a preventative drug. The drug should now only by administered to people with severe symptoms or chronic underlying illnesses, it said, in order to prevent a build up of resistance to the medication.
