The news comes just over a week after the same vaccine was authorized in the UK.

Credit: JEFF KOWALSKY/AFP via Getty Images

The Food and Drug Administration on Friday authorized a vaccine by U.S. drugmaker Pfizer, for emergency use, marking a pivotal step in the fight against the coronavirus pandemic and the hopeful return to normalcy.

Specifically, the emergency use authorization means the drug company, with its partner, German firm BioNTech, can begin to distribute the two-dose vaccine in America. The vaccine could start being distributed within days. Next, the FDA is expected to evaluate another vaccine from drugmaker Moderna.

“The FDA’s authorization for emergency use of the first COVID-19 vaccine is a significant milestone in battling this devastating pandemic that has affected so many families in the United States and around the world,” FDA Commissioner Stephen M. Hahn, said in a statement. “Today’s action follows an open and transparent review process that included input from independent scientific and public health experts and a thorough evaluation by the agency’s career scientists to ensure this vaccine met FDA’s rigorous, scientific standards for safety, effectiveness, and manufacturing quality needed to support emergency use authorization.”

Approving the vaccine for emergency use authorization is not the same as a full approval, which will require more time.

The vaccine, which CNBC reported was first recommended for approval by the Vaccines and Related Biological Products Advisory Committee on Thursday, has been approved for people 16 years old and older. 

Pfizer’s vaccine — a pair of doses, given three weeks apart — has a 95% effectiveness after the second dose, the FDA confirmed. The agency noted there are side effects with study volunteers most commonly experiencing reactions at the site of injection, headaches, fatigue, muscle pain, chills, joint pain, and fever, especially after the second dose.

The news comes just over a week after the same vaccine was authorized in the UK.

But while Pfizer plans to deliver tens of millions of doses across the globe by the end of 2020 — and more than 1 billion doses in 2021 — it could be many months before there are enough doses in the U.S. to go around.

The Centers for Disease Control and Prevention has recommended healthcare workers and residents of long-term care facilities be vaccinated first. Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, has told the BBC the U.S. can very quickly “begin administering the vaccine to the higher priority groups.”

“It’s going to be a task for us to be transparent and articulate in letting the public know that in fact we are dealing with a safe and highly efficacious vaccine,” he added. “Because a highly efficacious vaccine does not mean much if we don’t have the overwhelming majority of the people taking the vaccine.” 

On Tuesday, the UK started distributing the Pfizer vaccine, including to a 90-year-old grandmother who, to much applause, became the first person in the world to receive it outside a clinical trial, Reuters reported. Britain has ordered enough doses to vaccinate 20 million people.

The UK has since issued a warning to anyone with a history of food- or medicine-related anaphylaxis after two reports of anaphylaxis and one report of a possible allergic reaction were cited, Reuters also noted.

The vaccine will likely create a huge boost for a beleaguered travel industry (with proof of inoculation potentially required to cross international borders in the future), but experts have warned travel won’t significantly rebound until at least mid-2021.

In the meantime, even vaccinated people will still have to wear a mask, social distance, and maintain the safe behaviors the world has adapted to learn in 2020, the NYT noted, since vaccine trials only tracked how many people became sick with COVID-19 and didn’t track whether or not vaccinated people could become asymptomatic carriers.

“A lot of people are thinking that once they get vaccinated, they’re not going to have to wear masks anymore,” Michal Tal, an immunologist at Stanford University, told the paper. “It’s really going to be critical for them to know if they have to keep wearing masks, because they could still be contagious.”

Alison Fox is a contributing writer for Travel + Leisure. When she’s not in New York City, she likes to spend her time at the beach or exploring new destinations and hopes to visit every country in the world. Follow her adventures on Instagram.