Covid: Cardiff and Vale health board issues avoid A&E warning
People have been urged not to go to hospital A&E departments unless they have a life-threatening issue.
Cardiff and Vale (CAV) health board said it was expecting to experience the "most challenging period in NHS history" over the winter months.
It said the coronavirus pandemic continued to put services under strain.
However, it added, plans were in place to cope but asked the public to play their part too.
A spokeswoman said: "Our emergency unit remains increasingly busy, we would like to take the opportunity to remind people that if their condition is not life or limb threatening they can call our CAV 24/7 service on 0300 10 20 247 and our team will assess them and direct them to the most appropriate service.
"We would also like to encourage people to get vaccinated. Getting vaccinated provides the best protection against serious illness from viruses such as the flu and Covid-19."