The public has been asked not to visit a ward in Limerick Regional Hospital as four patients are being treated for the so-called winter vomiting bug.
There are also three suspected cases of the bug in the hospital.
Patients became infected with the bug over the past week. One person who had been infected has been discharged, leaving four confirmed cases.
The Mid-Western Health board has asked for the public's co-operation when visiting ward 3B where the confirmed patients are being treated and those suspected of having the bug are being investigated.
