CDC: 1 in 4 Americans have received at least one dose of COVID-19 vaccine

A resident of Koreatown receives a COVID-19 vaccination dose outside the Karsh Family Social Service Center on March 18, 2021 in Los Angeles, California. (Photo by Mario Tama/Getty Images)

The Centers for Disease Control and Prevention reported Tuesday that one in four Americans have received at least one dose of the COVID-19 vaccine, a critical milestone in the fight to get the country vaccinated.

The agency reported that more than 83.9 million Americans have gotten a shot, representing 25.3% of the total U.S. population. More than 45 million Americans have been fully vaccinated, or about 13.7% of the population.

The CDC said more than 164 million doses have been delivered, and more than 128 million doses have been administered.

The vaccine rollout has picked up the pace ever since the first dose of vaccine in the U.S. was given on Dec. 14, 2020 in New York to an intensive care nurse.

The country now has three vaccines in its stockpile from Pfizer-BionNTech, Moderna and Johnson & Johnson that have been approved for emergency use by the U.S. Food and Drug Administration. AstraZeneca, a fourth company, hopes to have its vaccine greenlighted by the FDA by April.

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On March 19, the U.S. cleared President Joe Biden’s goal of injecting 100 million coronavirus shots more than a month before his target date of his 100th day in office. 

With the nation now administering about 2.5 million shots per day, Biden, who promised to set a new goal for vaccinations, teased the possibility of setting a 200 million dose goal by his 100th day in office.

Despite the vaccination rollout, health officials are still concerned that the efforts are competing with the rise in COVID-19 variants.

"The way we can counter [U.K. variant] 1.1.7, which is a growing threat in our country, is to do two things: to get as many people vaccinated as quickly and as expeditiously as possible with the vaccine that we know works against this variant and, finally, to implement the public health measures that we talk about all the time ... masking, physical distancing and avoiding congregant settings, particularly indoors," the government’s top infectious disease expert Dr. Anthony Fauci said last week.

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The head of the CDC, Dr. Rochelle Walensky, urgently warned state officials and ordinary Americans not to let down their guard, previously saying she is "really worried about reports that more states are rolling back the exact public health measures that we have recommended."

Walensky’s comments came as more states lifted restrictions. Iowa, Texas, Mississippi, North Dakota and Texas lifted their mask mandates in recent months. Arkansas Gov. Asa Hutchinson said Sunday that he believes his proposal to remove a mask mandate intended to slow the spread of the coronavirus will take place as planned at the end of the month.

According to Johns Hopkins, more than 29.8 million Americans have tested positive for the virus and more than 543,000 Americans have died since the pandemic started more than a year ago. 

The Associated Press contributed to this report. This story was reported from Los Angeles.