Newmarch House resident tests positive for old infection of COVID-19

Confusion over the coronavirus test of a resident at the aged care facility at the centre of one of Australia's deadliest outbreaks has been clarified.

Last night it was reported a resident at Newmarch House had tested positive to the virus, and this morning NSW Health said the test was a false-positive.

However Anglicare Sydney, who operate the facility in Kingswood, in Sydney's west, said the test picked up traces of the virus still in the person's system.

"Further clarification from NSW Health indicates that rather than a false-positive, pathological evidence has confirmed the swabs taken from the resident shows signs of the old infection," an Anglicare Sydney spokesperson this morning.

The person is no longer infectious, the spokesperson confirmed.

Epidemiologist Professor Mary-Louise McLaws said a false positive result is not uncommon, and facilities should be prepared for these outcomes.

"This patient shouldn't pose any risk to any other resident there," Professor McLaws told Today.

READ MORE: Families prepare class action over Newmarch House deaths

"It's not uncommon that people have a very weak result for many weeks, sometimes some patients have a weak positive result months afterwards and it often depends on how sick they were the first time round."

Professor McLaws said the tests look for remnants of the virus.

"So this virus may not be alive when it's found."

She said the test can't identify if the virus is a current or past infection, or if it was just "a remnant" of having had the virus.

Residents of aged care facilities remained "very vulnerable", she said.

Over a two month period this year, coronavirus turmoil was seen at Newmarch House, with 19 people killed, and 37 residents and 34 staff infected.

The outbreak was one of the deadliest periods of the COVID-19 pandemic seen in Australia.

On June 15, NSW Health declared that outbreak —believed to have been sparked by an infected staff member who worked multiple times with extremely mild symptoms — over.

The response from Anglicare and government bodies has since been harshly criticised after new infections continued to appear more than two weeks into a full lockdown of the home.

Family members of some of the elderly residents who died during the outbreak are now preparing to launch a class action against operators, Anglicare.

READ MORE: All the latest COVID-19 cases in NSW

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