Pfizer will supply around 600 immunization sites across country in coming days

An illustration picture shows vials with Covid-19 Vaccine stickers attached, with the logo of US pharmaceutical company Pfizer, on November 17, 2020. (Photo by JUSTIN TALLIS/AFP via Getty Images)

Pfizer’s coronavirus vaccine will roll out across the United States starting Sunday, with further deliveries planned for Tuesday and Wednesday.

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.

The Centers for Disease Control and Prevention Advisory Committee on Immunization Practices met on Saturday to finalize and accept the language for guidelines regarding the distribution of the vaccine, though governors and state health departments will have the final say as to how they will prioritize immunizations.

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Initially, about 3 million shots are expected to be shipped nationwide, according to officials with Operation Warp Speed. A similar amount is to be held in reserve for those recipients’ second dose.

The first doses will ship from Pfizer’s manufacturing plant in Kalamazoo, Mich.

The greatest challenge Pfizer faces is the storage requirements: The vaccine needs to be kept at -94 degrees Fahrenheit. The company has developed dry ice containers to address the issue.

The Associated Press contributed to this report.