Swaffham’s Community Hospital has been closed to new admissions due to a small number of patients being treated for flu.
A hospital spokeswoman said that, in the interests of patient safety, the ward was expected to remain closed to admissions for five days from the last case of infection.
It is anticipated it will be closed until Monday.
To help reduce the spread of infection, people are being asked to avoid visiting if possible and visitors who have coughs and colds which could potentially be flu are also being asked not to visit friends and relatives until they are better.
The spokeswoman said: “Patients, being cared for on the ward, are being monitored and appropriate infection control and prevention measures are in place. Norfolk Community Health and Care NHS Trust apologises for any inconvenience.”