All three have received COVID-19 vaccinations - two of them with Pfizer - and 96 per cent of residents are vaccinated.
They have no symptoms and are in good spirits.
Summit Care is in lockdown, with deep cleaning and testing of all residents and staff underway.
Prime Minister Scott Morrison announced on Monday that COVID-19 vaccines would be mandatory for aged care workers, but they won't have their first dose until mid-September.
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