More than 425 sites across the U.S. will receive COVID vaccines Tuesday and another 66 locations will get the treatment Wednesday, health officials said.
Many locations in all 50 U.S. states and Puerto Rico received shipments of Pfizer Inc. and BioNtech SE's vaccine Monday.
"Literally millions of doses right now are getting out there to the American people. And by next week, we believe we could be having a second vaccine," Health and Human Services Secretary Alex Azar said.
"By the end of February, what you saw today could be replicated a 100 million times, a 100 million shots in arms between the first and booster vaccine," Azar said.
Some 2.9 million doses of the vaccine will be distributed this week, Operation Warp Speed chief operating officer Gen. Gustave Perna said.
A further 2.9 million doses will be kept in reserve.
The vaccine received an emergency use authorization from the U.S. Food and Drug Administration late Friday - triggering the largest vaccination in America.
Thousands of Americans are now being vaccinated against COVID-19 after a critical care nurse in New York became the first person to receive a shot Monday. Sandra Lindsay, an African American intensive care unit nurse at the Long Island Jewish Medical Center in Queens, was the first in New York State to receive the vaccine.
"It didn't feel any different from taking any other vaccine," said Lindsay, who has treated some of the city's sickest COVID-19 patients for the past months.
"I feel hopeful, relieved. I feel like healing is coming. I hope this marks the beginning of the end of a very painful time in our history. I want to instill public confidence that the vaccine is safe."
Lindsay was the first of more than 100 million people, or 30% of the population, that might be inoculated by the end of March.
Health care workers and residents of long-term care homes will be first in line for inoculations of a two-dose vaccine given about three weeks apart, Operation Warp Speed chief adviser Dr. Moncef Slaoui said.
Slaoui said the U.S. hoped to have 40 million vaccine doses, or enough for 20 million people, distributed by the end of this month. This total will include vaccines from both Pfizer and Moderna Inc.
Developed by Pfizer and its German partner BioNTech, the vaccine given to Lindsay received emergency-use authorization from the U.S. Food and Drug Administration on Friday after it was found to be 95% effective in preventing illness in a phase-three clinical trial.
The first 2.9 million doses of the vaccine were shipped to distribution centers around the U.S. on Sunday.
As of late Monday the U.S. had more than 16 million cases and 297,000 deaths, based on data from the U.S. Centers for Disease Control and Prevention. There were more than 213,000 new cases Monday along with some 2,300 new deaths.
In California, Helen Cordova, an ICU nurse at Kaiser Permanente in Los Angeles, became the first in the state to get the vaccine, according to Gov. Gavin Newsom. "History made," tweeted Newsom about the historic event.
In a video posted to Twitter, Cordova said she's "feeling great."
"I'm excited. I'm hopeful," she said. "I really encourage everyone to consider receiving the vaccine so we can start putting an end to this pandemic."
In Florida, Vanessa Arroyo, 31, a nurse at Tampa General, was the first to receive the vaccine, according to Gov. Ron DeSantis.
Nearly 100,000 doses of the vaccine arrived Monday at five regional hospitals. Gov. DeSantis was at Tampa General's loading dock to sign for and receive the first shipment.
Dr. Charles Lockwood, dean of the University of South Florida College of Medicine, compared the arrival of the vaccines to the first moon landing in 1969.
"From a health care perspective, this is our magic Neil Armstrong moment," said Lockwood.
