Management at the Midlands Regional Hospital in Mullingar are asking visitors to stay away unless absolutely necessary.
The hospital's Emergency Department is described as extremely busy this morning.
Management are asking the public, where possible, to telephone their GP/or pharmacist in the first instance to seek the best advice, rather than presenting at the hospital.
According to the INMO, 28 people are waiting on trolleys or chairs at the ED in Mullingar - as well as 16 at Sligo University Hospital.