Midland Regional Hospital Mullingar has suspended ward visits until further notice.
A spokesperson told RTÉ News the decision was taken due to a high number of Covid-19 cases detected in the hospital recently.
The hospital's Emergency Department has also been very busy over the past month.
''This is a precautionary measure in order to protect the safety of patients and staff. It will also help reduce the spread of infection,'' the hospital said in a statement.
There will be no changes to maternity services and maternity ward visiting arrangements.
Parents will still be able to visit children in hospital and families can visit patients at end-of-life.
Immediate family members will also be able to visit patients in ICU/CCU, the hospital said.
Where visiting is allowed, exemptions are limited to one person per patient only (except where wheelchair and other support for a relative visiting may be needed).
Hospital management said it is hoped that the restrictions will be in place for a short period.
They have asked members of the public to co-operate with "these necessary visiting restrictions".