There is no sustained community-based transmission of coronarvirus in Western Australia, the health minister says, as it has been three weeks since a locally-acquired infection couldn’t be linked to a known contact or overseas travel.

WA confirmed its fifth consecutive day of no new cases on Monday, while the number of active cases had fallen to just 15.

Roger Cook said the last time a locally-acquired case from an unknown source was recorded was April 12.

“It’s much longer than the incubation period of the COVID-19 virus, so we can say that’s well and truly out of our system,” he told reporters.

“We have no sustained community-based transmission in WA.”

Of the state’s 551 confirmed cases, the origin was not known for 14 per cent, Mr Cook said.

That compared to 46 per cent in South Australia.


“So you can see as one of the gateway cities of Australia … we’ve borne our brunt of people returning from overseas.”

Seven patients are in Perth hospitals, including three in intensive care.

More than 1000 people remain in mandatory quarantine, including 210 people on Rottnest Island.

An 83-year-old woman became ninth person to die from the virus in the state last week.

She was the fifth WA resident to succumb to the disease, while the other four people were passengers and a crew member from the Artania cruise ship.