Pfizer Inc. has initiated in shipping its coronavirus vaccine, dispatching trucks from a Michigan plant carrying the shots to hospitals and health departments and hospitals preparing to deliver the injections against a soaring pandemic.Trucks that belong to United Parcel Service Inc. and FedEx Corp rolled out of Pfizer’s Kalamazoo, Mich.,plant bound for central distribution centers and moving towards 145 health departments and hospitals around the US.The trucks were carrying over 500,000 injections of the vaccine, which must be preserved at -94 degrees Fahrenheit.Health-care workers treating coronavirus patients, nursing-home residents and maybe others could start getting vaccinated as soon as Monday, though it may take a day or two for facilities to train staff and initiate injections.