WEEHAWKEN, N.J. (CBSNewYork) — Health care workers were first in line to get vaccinated for the coronavirus this week, and with Moderna joining Pfizer in being approved by regulators, millions more doses are on the way.

But the roll-out hasn’t been perfect.

The vaccines have arrived in all 50 states, including New York, beginning the largest immunization effort in history.

But some states, including New Jersey, aren’t getting the expected number of doses.

More: New Jersey Plans To Open Mega Vaccination Sites In January

New Jersey is now getting 20% fewer doses than expected of the Pfizer and Moderna vaccines for the month of December with little explanation for the shortfall given to Gov. Phil Murphy.

“Number one, I don’t think we’ve gotten a satisfactory reason why,” Murphy said Friday.

CORONAVIRUS PANDEMIC

The head of Operation Warp Speed, Army General Gus Perna, apologized Saturday for the reduced deliveries and took responsibility for a “miscommunication” that took place.

“When we had to decide what was going to eventually be shipped out, I had to lower the allocations to meet the releasable doses that were presented to me,” Perna said. “So to the governors, to the governors’ staffs, please accept my personal apology if this was disruptive in your decision making and in your conversations with the people of your great state.”

Perna’s apology came after the FDA authorized the Moderna vaccine for emergency use, offering another weapon in the nation’s fight against the virus.

More from CBS News: FDA Authorizes Moderna’s Coronavirus Vaccine For Emergency Use

“We will crush this outbreak that has really terrorized us for the last 11 months,” said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases.

So far, the CDC says about 272,000 Americans have been vaccinated, but the number of infections continues to spike in the U.S. with 250,000 new cases reported Friday alone.

This comes as 84 million Americans plan to travel for Christmas.

CORONAVIRUS: NY Health Dept. | NY Call 1-(888)-364-3065 | NYC Health Dept. | NYC Call 311, Text COVID to 692692 | NJ COVID-19 Info Hub | NJ Call 1-(800)-222-1222 or 211, Text NJCOVID to 898211 | CT Health Dept. | CT Call 211 | Centers for Disease Control and Prevention

Dr. Jake Deutch is an emergency medicine physician and founder of Cure Urgent Care in New York City. He worries people are letting their guard down too soon.

“Everybody is looking for that loophole. ‘How can I see my family? What can I do to stay safe?’ The only thing that we can do to stay safe is stay home,” he told CBS2’s Nick Caloway.

Moderna will begin shipping 6 million does all over the U.S. this weekend, reaching health care providers by Monday.

Nick Caloway contributed to this report.

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