(Muscatine, IA) -- The Mississippi Valley Blood Center is urging people to donate blood after blood drives were cancelled to help prevent the spread of coronavirus. Public Relations Manager Kirby Winn says 60-percent of the blood supply comes from blood drives. The blood center is requesting people make an appointment to donate blood to allow for social distancing. The center says a technician will screen people for COVID-19 symptoms at the door before allowing anyone inside.