The health secretary says the new rule aims to give shoppers confidence and protect retail staff.
Modelling suggests there could be a deadly second peak, killing more than 100,000 people in the UK.
The governor has rolled back reopening plans across the state as virus cases soar.
The move at Wales' biggest A&E department does not apply to emergency cases.
"Targeted action" means outbreaks are being swiftly dealt with, the health secretary says.
A 24-hour tally of 15,299 new coronavirus cases eclipses the worst rates seen in New York in April.
Llamas' specially evolved small antibodies are the basis for a coronavirus treatment breakthrough.
The father of a five-year-old who died from cancer says he is proud she could help researchers.
It is one of several restrictions introduced by President Ramaphosa amid rising infection rates.
A hairdressing salon is using its bond with customers to help them with mental health issues.