Health Minister Roger Cook says the woman, who takes the state's tally to 546, did not attend work with symptoms.

WA now has just 96 active cases, including 10 in regional areas, and has recorded single-digit growth since April 10.

Mr Cook says the state is well-placed to resume some elective surgery in line with Tuesday's national cabinet resolution.

"These consistently low numbers have allowed us to better prepare and better plan," he told reporters.

The health department expects hospitals should be able to quickly clear their backlog of serious elective surgery cases.

"Over this period we will clear the most urgent and depending on how we go with our COVID numbers, ICU capacity and general capacity and PPE, we will try and increase further," director-general David Russell-Weisz said.

"We don't want any patient waiting for longer than they should do."

The government on Tuesday announced molecular analysers would be rolled out in regional WA, allowing COVID-19 testing results within an hour.

They will be used for higher-risk scenarios such as health care workers, police, hospital patients, people living in Aboriginal communities and areas with an increased risk of community transmission.

The first will be in Broome next week, then Kalgoorlie and Geraldton. Further roll-out to Port Hedland, Albany and Esperance is being considered.

Authorities will soon also begin testing some asymptomatic school students as part of a public health surveillance study.

Premier Mark McGowan said the swab tests would likely be deployed in areas with a greater prevalence of cases.

He said that of the 68,000 people working in the state's public and private schools, only one person had tested positive.

"Obviously spot-checking at schools will help allay any fears," Mr McGowan said.

"But all of the advice we've received is there's very little risk in schools."

There are 26 confirmed COVID-19 patients in Perth hospitals with five in intensive care.

Australian Associated Press