Director of the Centers for Disease Control and Prevention (CDC) Rochelle Walensky on Friday said the U.S. might need to "update" its definition for what it means to be fully vaccinated against COVID-19.

The CDC and Food and Drug Administration (FDA) have officially given the go signal for COVID vaccine boosters for people who meet specific requirements, Axios reported.

Walensky said not everyone is eligible for a boost. Thus, the definition has not been changed yet for what it means to be "fully vaccinated."

In a press briefing, Walensky noted that they have not yet changed the definition of "fully vaccinated," adding that they will continue to look at the matter.

The CDC director said those who are eligible to get boosters should go ahead and get it. The CDC currently defines being fully vaccinated as people who are ≥14 days post-completion of the initial series of an FDA-authorized COVID vaccine.

The Hill reported that White House COVID response coordinator Jeff Zients Jeff Zients said more than 70 million people are eligible to receive booster shots.

He added that more than 120 million Americans would become eligible for a booster in the coming months, including over 60 million vaccinated with Moderna and Johnson & Johnson, on top of the 60 million vaccinated with Pfizer.

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COVID Vaccine Boosters

A CDC advisory committee on Thursday had unanimously endorsed boosters of Moderna and J&J's COVID vaccines, CNBC News reported.

The CDC's Advisory Committee on Immunization Practices endorsed the Moderna boosters for elderly people and at-risk adults six months after they complete the first series of their shots.

It also endorsed J&J boosters for everyone 18 and older for people who received the primary shot at least two months ago.

However, the panel did not specify which vaccine should be used as a booster. Doctors will get to decide whether to mix and match the companies' doses to provide the best protection for the recipients.

The CDC data showed that the most common side effects reported after getting a third shot of an mRNA vaccine were pain at the injection site, fatigue, muscle pain, headache, and fever. There were also chills and nausea.

mRNA vaccines are the type made by Moderna and Pfizer.

Meanwhile, data available for J&J was more limited. However, people also reported fever, fatigue, and headache after receiving the second shot of that vaccine.

Dr. Macaya Douoguih, head of clinical development and medical affairs for J&J's vaccines division Janssen, said there is no data showing that people are at increased risk of a rare but serious blood clot after a second shot.

Booster shots have remained a divisive topic as many people in the U.S. and other parts of the world have yet to receive even one dose of a vaccine.

The World Health Organization (WHO) has called on wealthy countries to hold off on distributing boosters, while some scientists are not convinced most Americans need it right now.

READ MORE: Moderna Scientists Warn Against New COVID Variants That Could Drive a New Wave of Transmission

This article is owned by Latin Post.

Written by: Mary Webber

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