A possible new COVID-19 case at a western Sydney aged care home which was at the centre of a major outbreak earlier in 2020, has been cleared after testing revealed it was an old infection.

Newmarch House operator Anglicare initially said it was investigating a possible case after the elderly resident tested positive but it was later thought to be a false-positive after a negative result.

However, further pathological evidence from NSW Health confirmed the swabs taken from the resident showed signs of the previous infection.

The Newmarch House resident is no longer infectious.

“We are all relieved and sincerely appreciate the support received from NSW Health,” Anglicare said on Tuesday.

Nineteen Newmarch House residents died from COVID-19 when it swept through the facility, infecting more than 70 staff and residents earlier this year.

The home has been free of the infection for more than two months.

A report released in August found staff shortages and inadequate protective gear had exacerbated the outbreak.

Meanwhile, NSW health authorities are concerned about low COVID-19 testing rates as the school holidays approach.

Only four new cases were detected across the state in the 24 hours to 8pm on Sunday, including three returned travellers in hotel quarantine and one locally acquired case linked to a known cluster.

On Monday, NSW Health acting director Christine Selvey urged people with even the mildest symptoms to get tested.

The NSW public school holidays start on September 26, and many people are expected to travel throughout the state in the following fortnight.

“Testing numbers have dropped over the past two weeks and this is a concern particularly in areas like south-western, western and south-eastern Sydney,” she said in a video update.

More than 9300 people were tested in the latest reporting period, down from 14,426 the previous day.

Although weekend test numbers usually drop, Sunday’s figure was well below recent weekend numbers which have been in excess of 20,000.

The locally acquired case announced on Monday was a close contact of a previous case who attended the Eastern Suburbs Legion Club.

Meanwhile, Premier Gladys Berejiklian is urging other states to accept their fair share of returned overseas travellers into hotel quarantine.

“NSW welcomes back around 2500 people every week, and we know the hotel quarantine system in NSW is managed well, but we’re doing so much more than all the other states combined,” she said.

“I would love to see the other states take on their fair share.”

More than 25,000 Australians stuck overseas might not make it home for Christmas unless the cap – currently 4000 per week – on international arrivals is increased.