Three people have been taken to Wollongong Hospital for treatment, while the other three - who are clinically well - have been transferred to Lawrence Hargrave Private Hospital in Thirroul for monitoring.

IRT chief executive officer Patrick Reid said the decision to transfer the residents was made in consultation with the residents and their families, the Illawarra Shoalhaven Local Health District, and Commonwealth agencies.

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"We are doing everything we can to ensure the best care possible for the affected residents and to protect all other residents and staff," Mr Reid said.

"Our thoughts are with the six residents and their families.

"Meanwhile our focus remains on minimising the risk to other residents and staff.

"All residents continue to be cared for in their rooms and we are supporting them with activity packs and access to video calls with friends and family."

IRT has advised that all other resident and staff tests have returned negative results, but they will be tested again today.

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The organisation confirmed on Thursday that an initial two residents had tested positive for the virus, and at that time one was asymptomatic while the other had mild symptoms.

Twenty-seven employees who had been in contact with these residents were put on paid leave.

IRT said 87.5 per cent of residents were fully vaccinated and 95 per cent had had their first dose, while almost all staff were fully vaccinated, with a small number awaiting their second dose.

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