Visitors are still not allowed at a hospital after it was forced to declare a critical incident.

St Richard’s Hospital says it is still under “significant pressure” after a norovirus outbreak saw the site close itself off to stop the spread of the illness.

The critical incident declared on Friday evening was stood down on Sunday afternoon, but the Chichester hospital is still only accepting visitors in exceptional circumstances.

Dr George Findlay, chief executive of University Hospitals Sussex NHS Foundation Trust who run the hospital, said: “Declaring a Critical Incident is a really serious step to take, but we did not have an alternative. We apologise to anyone who is inconvenienced by this, or worried.

“I absolutely understand that people want to visit their relatives and friends in hospital, but we must still ask that people stay away. We simply must reduce the risk of spreading the virus more – many of our patients are vulnerable to infection and would be at risk.

“Our staff need the time and space to get services back to normal. If you need them, they will be there for you, but please understand that they need your help and support, too. Only use them if you have to.

“Our message to people is simple – if you are not absolutely sure you need A&E, please use the alternatives first. Visit 111.nhs.uk, or call 111, and let the experts there give you help and advice.”

A critical incident means that hospitals such as St Richard’s cannot function as normal due to facing extraordinary pressures.

As part of the critical incident ambulances were diverted from Chichester while almost 30 beds were closed to contain the spread of norovirus.

Patients are being asked to use alternatives to A&E where possible.

The critical incident was declared on Friday evening but was stood down at 12pm on Sunday, April 7.

Visitors are still not allowed into St Richard’s unless visiting someone receiving end of life care or visiting children.

The decision to re-admit visitors is being reviewed daily.