Lyndoch Living will close the doors of its residential facilities to all visitors except essential services such as doctors and allied health professionals.
The lock down at its Warrnambool and Terang facilities will come into effect from Midnight on Wednesday.
Chief executive officer Doreen Power said that while Lyndoch had activated its infection control practices and visitor protocol, it had now decided to initiate precautionary closure of the residential areas to ensure the safety of every resident.
"This is not a decision we have taken lightly, and we believe it is in the best interests of our residents," Ms Power said.
"In the event of special circumstances, we will make arrangements on a case-by-case basis," she said.
Family members are encouraged to contact their loved ones by phone or electronic devices.
"Thank you for your cooperation and support of our arrangements to protect our residents in light of the current health emergency," she said.
"Together we can help keep the people we love and care for healthy and well."
In a letter to families, Ms Power said that it was implementing all possible measures to prevent the spread of the illness in our facility and to protect the residents.
"Covid-19 is a new virus, which means there is no immunity to it," she said.
"The World Health Organisation has declared COVID-19 a pandemic, and evidence suggests that the risk is greater in older people aged 70 and over."
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