By Trang Do

PHILADELPHIA (CBS) — Deliveries of nearly 3 million doses of Pfizer’s COVID-19 vaccine began around 8:30 a.m. Monday, after FedEx and UPS planes carrying them touched down at more than 30 cities across the country, including Philadelphia.

“Some doses arrived this morning. We have confirmation that some doses will be coming tomorrow, and then the remainder will be arriving on Wednesday,” said Amber Tirmal, the city’s immunization program manager.

Tirmal said Philadelphia will receive 13,650 doses this week to be split among the department and all of the hospital systems. She expects vaccination of frontline health care workers to begin Wednesday.

“Each individual hospital and health care system are making their own determinations about who within their organizations that they want to prioritize,” she said.

The shipments landing at Philadelphia International Airport are flown on UPS cargo planes, which has an air hub just off of airport property.

PHL Airport Communications Director Florence Brown said crews are ready to ensure that the planes carrying this precious cargo can safely land and take off, even if Wednesday brings heavy snow.

”In the event that that occurs, the airport’s responsibility will be to help prioritize those aircraft, de-ice them quickly and get them back in the air as quickly as possible,” Brown said.

The vaccine shipments, packed in special boxes that will maintain the ultra-cold temperature they need for several days, are as anticipated and closely monitored as Santa Claus’ flight on Christmas Eve.

“It’s been a difficult planning process, but it feels really thrilling to have doses that are almost about to be in people’s arms, and that we can sort of, begin to get back to what we’ve all sort of lost,” Tirmal said.

Tirmal said it’s hard to predict how long the first phase of vaccinations of health care workers will take before it is opened up to other groups, but FDA approval of Moderna’s vaccine would definitely help speed up that timeline. An FDA committee is scheduled to meet Thursday to discuss that potential.

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