By Evie Fordham | FOXBusiness
The first shipment of the Pfizer coronavirus vaccine is loaded at the Kalamazoo, Michigan facility.
Sunday is a historic day in the nation's fight against the coronavirus pandemic.
The loading process began Sunday morning. The first wave of deliveries will see 150 locations supplied with the Pfizer-BioNTech’s COVID-19 vaccine, and a further 450 sites will see supplies in the second shipment.
The vaccine is timed to arrive Monday morning so that health workers can receive the shot before administering it themselves.
Shipments of the Pfizer vaccine will set in motion the biggest vaccination effort in American history at a critical juncture of the pandemic that has killed 1.6 million and sickened 71 million worldwide.
Initially, about 3 million doses were expected to be sent out, and the priority is health care workers and nursing home residents as infections, hospitalizations and deaths soar in the U.S. With numbers likely to get worse over the holidays, the vaccine is offering a bright spot in the fight against the pandemic that's killed nearly 300,000 Americans.
Federal officials say the first shipments of Pfizer’s vaccine will be staggered, arriving in 145 distribution centers Monday, with an additional 425 sites getting shipments Tuesday, and the remaining 66 on Wednesday. The vaccine, co-developed by German partner BioNTech, is being doled out based on each state's adult population.
Fox News' Peter Aitken and the Associated Press contributed to this report.