"We know it wasn't a member of staff or a resident but there are a number of other possible vectors, such as on a piece of fruit or an iPad screen," he said.

"We've all become Miss Marple at one point or another trying to work it out.

"We haven't been able to identify an individual, and we are one of only two outbreaks in Australia with an unknown cause - it shows how insidious this virus is."

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The outbreak, first detected on October 6, has so far infected 26 residents and six staff members. Sadly, four residents who caught the virus have since passed away.

"It's hard to talk about death, and in situations like this it's doubly hard," Mr Reid said. "Staff and residents often become very close, so it's hard on them too."

In heartening news, all Monday's tests of staff and residents came back negative. Seven residents are now considered recovered.

Seven cases in total were detected in the region, with four in Wollongong, one in Shellharbour, none in Kiama and two in the Shoalhaven.

Mr Reid said staff and residents were experiencing pandemic fatigue.

"It's a long process from outbreak management to infection control and then stabilisation," he said.

"Staff are working in full PPE. It's hot, it's heavy, and they're long days.

"We have PPE spotters to make sure there are no breaches - it's easy to forget something when you're tired.

"We're looking at rosters and how we can manage breaks for affected staff.

"We're mindful of residents too - they're confined to their rooms and isolation is a challenge for anybody.

"We're also concerned about deconditioning, and are bringing in physiotherapists in full PPE when we can to get them up individually."

To combat loneliness and isolation staff are trying to create bright moments for residents, whether it be providing the tools to engage in their favourite hobby, or a specially-prepared meal.

"Staff are putting in a lot of effort to give each resident a bit of a lift," Mr Reid said.

NSW Health said on Tuesday 93.1 per cent of people 16 and over in NSW have received one dose of a COVID-19 vaccine and 85 per cent of adults are now fully vaccinated.

For aged care residents who are keen to get back out into the world, these numbers must continue to climb.

Mr Reid said vaccination was the only way to ensure vulnerable groups are not put at risk as the state continues to open up.

"Vaccination is the pathway out of this," he said.

"There is fear amongst aged care providers that as we open up the virus will get in.

"We are a care and accommodation provider, not a prison. We usually encourage residents to get out and about and we want them to be able to do so safely.

"We want to be able to welcome visitors back in as well. We miss their energy, and we miss the volunteers who are a great support to residents and staff.

"For peace of mind, mental health and social connectivity we need as many people vaccinated as possible."

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