Jones said any risk to other workers or people shopping at the time was very low but could not be entirely ruled out.
The supermarket had very good hygiene rules in place including: regular wiping down of surfaces and trolleys, screens for staff on the check-out counters, as well as robust staff hand hygiene including encouraging regular hand sanitising.
"The hygiene rules in place at the supermarket will help lower the risk further, but we ask anyone who has developed illness, even very mild illness such as a cough, sore throat, shortness of breath, runny nose or loss of smell and taste, to contact Healthline 0800 358 5453 or call their GP."
New Zealand also recorded its second coronavirus-related death in its latest update on Friday.
The death was of a woman in her 90s, who died in Burwood Hospital in Christchurch.
Director of Public Health Dr Caroline McElnay updated the nation from the Beehive in Wellington and said the woman died on Thursday after having recently returned a positive test.
McElnay said, as has been seen around the world, Covid-19 could be fatal for elderly people with underlying health conditions.
The family would take time to grieve and the Ministry of Health's thoughts were with the family, she said.
She was one of the residents from the Rosewood rest home moved earlier in the week.
She had a number of age-related health conditions.
Because of level 4 lockdown conditions, her family wasn't able to visit her or be with her before she died in hospital.
There were 44 new cases of Covid-19 in the country - 23 confirmed cases and 21 probables announced on Friday, with the total number of cases now 1283.
There are 16 people in hospital. That includes five in ICU – one each in Hawke's Bay, Wellington, Waitemata, Counties Manukau and Southern DHBs. Two of these ICU patients, in Southern and Waitemata, are in a critical condition.
Hawke's Bay DHB confirmed it had a patient in ICU but that it did not require the patient to be on a ventilator.
Jones said the DHB's public health team was also actively investigating the contacts of a case confirmed on Wednesday.
This woman in her 20s had been at Eastern Institute of Technology (EIT), Taradale, on March 23 and 24, before becoming aware of her illness.
Jones said all but one of the known contacts of this person had been contacted.
"While we still don't know where this person acquired the illness from we are following up a number of leads and should know more in the next few days.
"While it is unlikely that anyone who hasn't already developed illness will do, I urge everyone to be vigilant."