Tamiflu is used to treat people suffering from swine flu
A man suffering from swine flu is critically ill in St James's Hospital in Dublin, it has been announced.
The man, who is his 30s and originally from Bratislava in Slovakia, was admitted to the hospital late last week.
It is understood he has been working in the Republic for several years.
The hospital said that all necessary precautions were being taken and that the relevant agencies were being kept "fully informed".
According to the Republic's Department of Health and Children, 226 cases of human swine flu have been confirmed in the state but no-one has died from the infection.
The Republic's health service executive is expected to brief the media on the man's condition later on Tuesday.
More than 100,000 people in the UK are estimated to have caught swine flu in the past week alone and 31 people have died after contracting the illness.
Northern Ireland has been one of the least badly effected areas in the UK.