Family and visitors have been turned away from the aged-care facility since last Thursday after at least two residents contracted the “stomach flu”.

Royal Freemason’s Benevolent  Institution chief operating officer Frank Price said residents could be isolated until Monday.

“The welfare of residents is paramount, if you don’t see your family members for a few days then that’s better than the alternative,” he said.

The lodge caters for at least 100 residents living in retirement units and low-care and high-care beds.

Federal government guidelines call for aged-care facilities to shut their doors if two or more residents contract gastro.

Autumn Lodge chief executive Chris Martin said she had also been informed of the outbreak, in keeping with protocol.

“We had a similar outbreak of gastro last year,” Ms Martin said.

Mr Price said he did not know how the outbreak started. “All it takes is for one or two people to become sick,” he said.

The lockdown was necessary because gastroenteritis weakens elderly people and makes them more vulnerable to contracting other diseases.  In the past year gastroenteritis and dehydration caused 611 hospitalisations among residents in New England.