Every time a customer sneezes, the cashiers freeze, wondering if they will be next to become ill with the coronavirus as they perform the essential service of helping families stock up on food during the 21-day lockdown.
A sneeze that would have solicited a pollen-season "bless you" two months ago, now has cashiers feeling frightened and uncertain.
A supermarket owner News24 spoke to on condition of anonymity said the fear and anxiety were becoming so bad that he decided to introduce a new rule: anybody wanting to shop at the store must put something over their mouth.
He said the World Health Organisation's advice on wearing a mask is very clear - it is for those in direct contact with people with Covid-19 or who are displaying symptoms of flu.
But, because staff are afraid, he put up a sign asking customers to cover their mouths with a scarf or bandana, just to keep the cashiers less frightened.
"We know that symptoms for Covid-19 take a long time to show," the owner said. "They are scared."
He has calculated how many people can be in the shop at a time, based on the metreage of the store, to maintain the distancing rules.
However, he thinks 150 is far too many people, and he has drastically reduced the number of people in the shop at a time, with no complaints from customers.
He said the customers are taking the physical distancing very seriously and are complying with recommendations to not be closer than a metre and a half. They do not mind waiting for their turn to be let in.
The police and Cape Town's Law Enforcement Unit have made turns at the shop to make sure all of the Disaster Act regulations and directives are being adhered to.
Before Covid-19, they had a good relationship with policing authorities and this continues during the lockdown.
They also take time out to reassure staff and thank them for their work.
Confused about regulations
He also knows that, if a staff member does test positive for Covid-19, the whole shop will close down, so it also makes business sense to reduce any risks to the business.
"We are just focusing on the recovery rate," he said.
Staff have hand sanitisers and shifts have been changed so that they can spend time with their families at home during the lockdown.
"We don't let things get in our head," he said.
Another supermarket owner in Strand, Cape Town, was left confused around some of the regulations following a visit from local police last week.
He told News24 that police officers visited his store on Friday to enforce lockdown measures. He was told that, as the store owner, he would have to ensure all customers and staff were wearing masks and covering their mouths, or be liable for a possible R10 000 fine.
"We've got no problem if that is the regulation, but we just want clarity. Other areas say you don't have to have it, but then in this area you do..." he questioned.
"You feel a little bit intimidated but, given the circumstances, we want to be as lawful as possible. Most of the customers have no issues with it... 99.9% are happy about it."
National police spokesperson Brigadier Vish Naidoo said: "This [customer masks] is not a requirement in the Regulations of the Disaster Management Act. I have requested my colleagues in Cape Town to provide me details about this."
*This story has been updated with police comment.
- Additional reporting by Paul Herman