The first shipments of Moderna Inc.'s COVID-19 vaccine have left warehouses and are headed to 64 jurisdictions throughout the U.S., said Gen. Gustave Perna, chief operating officer of the White House's Operation Warp Speed.

Vaccinations with Moderna's shot were scheduled to start Dec. 21, he said.

Moderna received emergency use authorization, or EUA, Dec. 18 for its COVID-19 vaccine from the U.S. Food and Drug Administration. That decision came a day after the agency's panel of outside experts voted 20 to 0, with one abstention, that the benefits of Moderna's COVID-19 vaccine outweighed its risks for use in people age 18 or older.

Moderna's EUA followed the FDA's Dec. 11 authorization of a COVID-19 vaccine from Pfizer Inc. and BioNTech SE.

Moderna developed its vaccine with the U.S. National Institute of Allergy and Infectious Diseases, or NIAID, under a longtime partnership initially funded by the Obama administration.

The COVID-19 vaccine "is how our country will begin to heal and move forward," NIAID Director Anthony Fauci said in a Dec. 18 statement.

On Dec. 19, Moderna moved vials of its vaccine from its fill-finish manufacturing sites to McKesson Corp., the U.S. government's central distributor, Perna told reporters during a briefing that day.

Trucks carrying the packages of Moderna's vaccine and ancillary kits containing syringes, alcohol wipes and other supplies began rolling out from FedEx Corp. and United Parcel Service Inc. on Dec. 20, the companies confirmed.

"The shipment of vaccines to help end the COVID-19 pandemic is among the most important work in the history of FedEx and our team is focused on the safe and efficient delivery of these critical shipments," Raj Subramaniam, the company's president and chief operating office, said in a Dec. 19 statement.

"This is a critically important initiative for UPS and we are committed to delivering what matters for as long as it takes," the company's CEO, Carol Tomé, said in a Dec. 20 tweet.

Unlike the ultra-cold temperature of minus 80 degrees Celsius required for the Pfizer-BioNTech vaccine, the Moderna product can be shipped and stored at the standard freezer temperature, making it easier to be transported to small and more rural areas, Perna noted.

Allocation flub

About 8 million doses of the two vaccines — nearly 6 million of them Moderna's shots — are expected to start arriving Dec. 21 at over 3,700 locations in 64 jurisdictions throughout the U.S., Perna said.

As of midday Dec. 20, about 2.84 million doses of the Pfizer-BioNTech COVID-19 vaccine had been distributed and 556,208 doses had been administered, the U.S. Centers for Disease Control and Prevention reported.

Perna said the U.S. expects to remain on course to vaccinate 20 million people with both vaccines by the end of December.

But the U.S. Army general said he was solely to blame for the miscommunication that led to last week's allocations of the Pfizer vaccine initially forecast to states to be significantly cut, while the company said it had millions of doses sitting in its warehouse waiting to be shipped.

The initial COVID-19 vaccine allocation plans were mistakenly based only on the number of doses produced but not yet "releasable" by the FDA, Perna said.

"It looked very good on paper," he told reporters. "It was my fault. "I gave guidance. I am the one that approved the forecast sheets. I am the one that approved the allocations."

CDC panel endorsement

During a special Dec. 19 weekend session, a CDC advisory panel voted 11 to 0 in favor of recommending emergency use of Moderna's COVID-19 vaccine.

"This represents progress towards ending this horrific pandemic," said panelist Beth Bell, clinical professor of global health at the University of Washington.

Three members of the CDC's Advisory Committee on Immunization Practices, or ACIP, recused themselves from the vote because of conflicts of interest, such as participation in clinical trials of the product.

Anaphylaxis

At the ACIP meeting, the CDC said that as of Dec. 18, the number of cases of anaphylaxis reported in the U.S. with the Pfizer-BioNTech vaccine had grown to six. Two cases of allergic reaction had earlier been reported in the U.K.

Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, told reporters Dec. 18 that a possible "culprit" behind the allergic reactions may be polyethylene glycol — a component in both the Pfizer-BioNTech and Moderna vaccines — though he emphasized investigations were ongoing.

The FDA has required both vaccines to carry contraindications and warnings about anaphylaxis in their EUA labeling.

Sites administering the vaccines must also be equipped with treatments for anaphylaxis, such as epinephrine.

The CDC posted new recommendations on its website Dec. 19 about how to treat and report severe allergic reactions with COVID-19 vaccines.

Next priority groups

On Dec. 20, the ACIP voted 13 to 1 in favor of recommending the next phase of U.S. vaccinations include people age 75 or older and frontline essential workers, like firefighters, police, teachers, correctional facility guards, grocery store employees, public transition workers and U.S. mail carriers — the Phase 1b group.

The ACIP had earlier recommended that healthcare workers and long-term care facility residents and staff be first to get the shots — the Phase 1a group.

The ACIP panel said the Phase 1c group — persons ages 65 to 74 and 16 to 64 years with high-risk medical conditions and other essential workers — should soon follow.

Henry Bernstein, chief of pediatrics at North Shore University Hospital, said he voted against the recommendation because he felt that the older people in the Phase 1c group should be given the vaccine at the same time as those in Phase 1b.

Members of Congress and some senior administration officials started receiving COVID-19 shots Dec. 18.

President-elect Joe Biden was scheduled to get vaccinated Dec. 21.