The limitations on visits are intended to stop or slow the spread of the flu, flu-like illness and gastrointestinal illnesses.
Under the restrictions, patients can have two visitors at a time and they must be immediate family or next of kin.
The authority says people who are sick or live with others who are sick should not visit, while children under the age of 12 should stay away.
Visitors may also have to wear gloves, masks and gowns.
The district had its first lab-confirmed flu case two weeks ago and it has since spread to patients and staff.