As noted by the reporter, at public places with many passersby such as banks, public administrations, traditional markets... there are installed QR-code scanning points to serve epidemic prevention work. These QR codes are used to trace suspected COVID-19 cases, in order to limit the spread to the community. Currently, people can use their smartphones to make medical declarations via QR codes quickly. At the entrance and exit points of Hom - Duc Vien market (Hai Ba Trung district), the control of people entering and leaving using QR codes is strictly implemented. In case the phone is not connected to the network, the market manager will record the information on paper. In the market, each shop has its own QR code attached to the splash shields and ensures a safe distance./.