With the total number of confirmed cases now at 90, it's time to have "all guns blazing", the state's health minister Roger Cook said in announcing new measures for hospitals.

Of the new cases 15 are returning travellers, or those who have had close contact with travellers.

"These are West Aussies coming home who have obviously had contact with COVID-19," Mr Cook said on Saturday.

Five people are currently being treated in hospital, including one person in a critical condition in intensive care, Mr Cook said.

Those people won't be allowed visitors under a series of changes to come into effect from Monday, as hospitals ramp up measures to protect patients and staff from the spread.

Nobody will be allowed to visit confirmed coronavirus-infected patients, or those being tested for the infection.

All children under 16 will be banned from visiting hospitals.

Adult patients will be restricted to two visitors per day who can only visit for two hours - one in the morning and one in the evening.

Mr Cook said anyone with cold or flu-like symptoms or those required to self-isolate are banned from entering hospitals.

"One of the things we know COVID-19 does is prey upon the elderly and the vulnerable so it's important that we restrict the number of people coming to and from our hospitals," he said.

Hospitals will take a compassionate approach where there are language or cultural barriers.

Non-urgent elective surgeries will also be cancelled from Tuesday.

Only semi-urgent surgeries booked before Monday and all urgent surgeries will go ahead.

Australian Associated Press