A US tourist is being treated for swine flu at Roscommon County Hospital.
The man, who is in his 70s, had been visiting the area and was admitted to hospital on Saturday complaining of chest pain.
Test results confirmed the case of influenza A(H1N1) this afternoon.
He has been given the drug Tamiflu and is being treated in isolation. No one he had been in contact with is ill so far.
It is the 12th case of swine flu in Ireland since the outbreak in March.
The World Health Organisation says it is consulting governments today about changing the pandemic alert on the virus.
A spokesperson told RTÉ News there would be no announcement today on the matter.
