The supermarket said in a statement the staff member worked at Woolworths Spring Farm, in the Macarthur region, on Thursday.
“We’re making contact with our Spring Farm team members and will provide our full support to those self-isolating in line with the advice from health authorities,” the statement said on Sunday.
“While the risk of transmission to customers and team members is low, the safety and wellbeing of the local community is our priority.
“As a food retailer, we already have very high standards of cleaning and hygiene in place. As an extra precautionary measure, the store had an additional deep clean overnight.”
The Spring Farm store has since reopened.
Woolworths said it was still safe to shop in the store, but anyone who visited on Thursday and feels unwell should undergo testing.
Sydney’s southwest remains a pocket for coronavirus cases with Deputy Chief Health Officer Dr Jeremy McAnulty telling reporters on Saturday 45 cases were now attached to Casula’s Crossroads Hotel.
Dr McAnulty also told anyone feeling unwell who visited McDonald’s at Albion Park on July 15 between 2pm and 2.30pm “to watch carefully for symptoms” and present for testing.
A number of cases have also been associated with Casula’s Planet Fitness gym.
Dr AcAnulty urged anyone who visited the gym between July 4 and 10 to consider isolation or testing.
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