A super shop in the city was shut and its owner and staff were sent on 14-day quarantine on Sunday after one of the employees tested positive for COVID-19.
The shop, 'Basket', was initially closed after the staffer's father tested positive for coronavirus on Saturday, the first case in the port city.
Nazimuddin, manager of the super shop, said though the employee was on leave from March 25, they closed down 'Basket' following the administration's directive.
Sitakundu Upazila Nirbahi Officer Milton Roy said the owner and staff were sent on home quarantine.
Bangladesh on Sunday confirmed the detection of 18 new coronavirus patients, raising the total number of such cases in the country to 88.
It has so far reported nine deaths.