A COVID-19 outbreak linked to a Perth aged care home has grown to 17, while two residents at another aged care centre, and a staff member at a third have also tested positive to the virus.
The outbreak at the Juniper Residential Aged Care facility in Bentley started on Wednesday when cases were detected in a resident and a staff member.
That outbreak then increased to six the following day, with Premier Mark McGowan now saying it had since grown significantly.
"I understand it's up to 17 cases in total now," the Premier said.
Eight of those cases are residents, two are staff and the remaining seven are close contacts.
WA Health and the Commonwealth government are working with Juniper, a Uniting Care aged care provider, to contain the outbreak.
Separately, cases have now emerged at an aged care facility in Mandurah, about an hour south of Perth.
Jennifer Lawrence, the chief executive of aged care provider Brightwater, confirmed two residents had tested positive at The Cove.
In an email to family and friends of residents, she said both residents had been triple vaccinated.
"The health and wellbeing of our residents, staff, volunteers and families is our number one priority right now, so we have enacted our outbreak management plan and we are working closely with the Department of Health," Ms Lawrence wrote.
"This includes asking residents to remain in their rooms where possible, undertaking a deep clean of the site and testing all staff and clients for COVID-19.
"All visits to site have been stopped for now, but our communications support officers will be in touch to set up contact with your loved one at The Cove."
Late on Sunday, a case was confirmed in connection with a third aged care centre, Coolibah Care which is also in Mandurah.
Coolibah Care chief executive Amanda Crook said in a memo that a staffing agency had notified them that one of their staff members, who had been at the centre on Saturday afternoon, had since returned a positive rapid antigen test.
The Banksia wing of the centre has been closed to visitors and contractors.
WA Health said it was aware of the case and was waiting on the results of a PCR test following the positive RAT test.
The result is expected on Monday.
Community transmission number rises by 38
Western Australia has recorded another 38 local COVID-19 cases, with another five still under review.
There were 25 travel-related cases, bringing the total number to 68
Some were infectious in the community, but all are now in quarantine.
Ten were from positive rapid antigen tests (RATs), which provide a result in 15-30 minutes.
Sunday's COVID figures came from 4,395 tests at public and private clinics.
Mr McGowan said PCR tests were preferred, especially while the availability of those was still high.
But he said RATs were also acceptable and supplies of those were now increasing.
The Premier said the government now had 8.8 million of the tests and he expected that number to rise to 11.2 million within days and 100 million by the end of April.
Mr McGowan said supplies were also increasing in shopping centres and pharmacies.
It is mandatory to register all positive COVID results with health authorities.
Mr McGowan urged all West Australians to take the Omicron threat seriously and anyone with symptoms to get tested.
Aged care visitors a 'weak link', nurses union says
Australian Nursing Federation state secretary Mark Olsen said aged care was "probably our weakest link" in WA's healthcare sector.
"We have to put in place restrictions now and not when we're in the middle of an Omicron surge," Mr Olsen said.
"We need to restrict visitors that are going into our aged care facilities. That's a weak link of the aged care sector.
"And the reality is we need to do everything possible to stop the spread."
Mr Olsen said COVID-19 did not just put residents at risk but also the workforce.
"That is the one workforce where we are more short of workers than any other," he said.
"We've seen already over east where they have approximately 100,000 shifts every week unable to be filled."