NHS Tayside has been experiencing exceptionally high demand due to an increase in the number of patients being admitted to hospital with respiratory conditions and flu-like illnesses.
A spokeswoman for the health board said that over the past few weeks, two wards in Ninewells Hospital and one ward in Stracathro Hospital have been closed to new admissions due to flu-like illness.
Ward 7 at Stracathro Hospital reopened to new admissions on Thursday after being closed due to a small number of patients with flu-like symptoms.
Dr Anne Marie Karcher, lead infection prevention and control doctor, urged the public to avoid visiting hospital if possible.
She said: “In the past few weeks, NHS Tayside has closed a small number of wards to new admissions due to flu-like illness.
“There are many bugs and viruses currently circulating in the community, including flu, and therefore to help reduce the spread of infection, we are urging the public to avoid visiting their friends and relatives in hospital if they are suffering from respiratory illness or flu-like symptoms themselves.
“This will help reduce the spread of illness amongst patients and our staff.”