Prime Minister Scott Morrison has accused an unidentified north-west Tasmanian aged care worker of being dishonest about their contacts.

Key points: The PM says the actions of a "dishonest" healthcare worker prove the need for a coronavirus-tracking app

The PM says the actions of a "dishonest" healthcare worker prove the need for a coronavirus-tracking app The search is now on to track contacts of the worker in north-west hospitals and aged care centres

The search is now on to track contacts of the worker in north-west hospitals and aged care centres The Premier is warning of road blocks to help fight the north-west outbreak if necessary

The north-west is in the grip of an outbreak of coronavirus, with another 10 cases confirmed in the region overnight.

Tasmania COVID-19 snapshot Confirmed cases: 226

Confirmed cases: 226 Deaths: 13, 12 in north-west What do I do if I think I have coronavirus? If you think you might have COVID-19 phone your GP or the Tasmanian Public Health Hotline on 1800 671 738. Need an interpreter? Phone the Translating and Interpreting Service on 131 450 and tell them your language. For more information and factsheets: Visit the Tasmanian Government's coronavirus page here.

Mr Morrison has told Triple M north-west Tasmania was a classic example of the need for the Federal Government's coronavirus-tracking app.

"We've had someone down there not tell the truth to the contact tracers about where they'd been and who they'd been with and that means that a lot of people have been put at risk in north-west Tasmania," he said.

"They have been working in the health system more broadly, in the aged care system, so this has been very unhelpful."

The Prime Minister's office has confirmed the aged care worker he spoke of was the same worker mentioned by Public Health Services last night as having worked at three nursing homes and having tested positive.

Tasmanian Premier Peter Gutwein said during a statewide update on the crisis this morning that a healthcare worker, who had worked at the North West Regional Hospital and the North West Private Hospital, had also done shifts at three aged care facilities — Melaleuca Nursing Home in East Devonport, Eliza Purton Home for the Aged in Ulverstone, and Coroneagh Park in Penguin.

He said a resident in one of the homes was displaying "mild respiratory symptoms", and all residents and staff in the nursing homes would be tested on Friday.

Director of Public Health Mark Veitch said the search was now on for contacts of the healthcare worker.

"Yesterday, health authorities made sure that anyone who worked in any of the three nursing homes had not been in recent contact with the case," he said.

"As a result of that initial investigation, one person was sent home … because they had had contact with the case, when the case had worked at a nursing home about a week earlier.

"Today, we will be working with the residential aged care facilities, working through their rosters and identifying any people who may have worked on the same shift as the infected healthcare worker."

The healthcare worker had a shift at the Eliza Purton Home for the Aged in Ulverstone. ( ABC News: Manika Dadson )

Mr Veitch said neither he nor his contact tracing team had provided "specific advice" to the Prime Minister's office on the healthcare worker.

"We know that we may not always pull out all the right details we need, when we ask the questions first time. You don't want to assume that that's the end of the story," he said.

He said when the contact tracing team went back the second time, it "threw the net wider".

"That was why we extended the period of interest, where we thought there was a small risk of infection to the residential aged care facilities," he said.

Premier warns of roadblocks

A coronavirus police checkpoint operating outside Burnie on Friday afternoon. ( ABC News: Manika Champ )

Mr Gutwein also warned "roadblocks and checkpoints" would be used as police ramped up enforcement of the order to stay home, except for work travel, gathering essential supplies or seeking medical treatment.

He said the State Government had already gone "over and above" in putting in place measures to tackle the outbreak, including quarantining up to 5,000 people in the north-west.

But he said he was disappointed some people had not taken the restrictions seriously.

He said overnight he had heard people had been travelling to Launceston to shop at homeware store Spotlight and hardware store Bunnings.

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Meanwhile, 160 doctors and nurses from the nearby Mersey Community Hospital at Latrobe have sent the Health Minister's office a letter, outlining concerns about the lack of PPE and failure to close communal areas.

Sarah Courtney says she wants to ensure hospital staff feel supported. ( ABC News: Mitchell Woolnough )

Health and Community Services Union's Robbie Moore said morale was low and staff felt they had been "mistreated" throughout the process.

"They have real concerns that the outbreak that occurred at the North West Regional Hospital could very well happen at the Mersey if there isn't immediate action taken," he said.

Health Minister Sarah Courtney said matters raised were being addressed.

"If this number of my staff are obviously very concerned then I've asked for this to be investigated further," she said.

"We need to make sure that our staff not only are supported, but are feeling supported."

More mobile testing promised in north-west

Tasmania now has 180 coronavirus cases and seven deaths.

Ms Courtney said she was "pleased" people had been contacting healthcare facilities to get tested.

On Thursday, 272 people presented to clinics in the north-west for testing and mobile testing would be deployed there in coming days.

Tasmania has conducted just under 6,000 coronavirus tests.

Public Health Services' hotline has increased its capacity to handle the volume of calls by hiring an additional 50 staff.