Explainer: Who should get the COVID-19 booster shot?

(Tiếng Việt)

The Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) have authorized a third dose of the Pfizer and Moderna COVID-19 vaccines, which were initially two-dose vaccines. They also authorized a second dose of the Johnson & Johnson vaccine. 

Both federal agencies said that any adult over the age of 18, and who is six months from their second Moderna or Pfizer shot or two months from the Johnson & Johnson shot, should get a booster shot.

The U.S. Department of Health & Human Services have announced they will prepare to offer free booster shots of the COVID-19 vaccines for those who are eligible beginning the week of Sept. 20, 2021. 

Why is a booster shot necessary? Should you get the third dose of the COVID-19 vaccine? 

Who can get a COVID-19 booster shot?

Currently, any adult over the age of 18 should get a booster shot.

In addition, the CDC said that people eligible for a booster shot should be six months from their second Moderna or Pfizer shot or three months from the Johnson & Johnson shot. The CDC also said people can “mix and match” booster shots, meaning they can receive a vaccine booster that is a different brand from their original shots (for example, Pfizer recipients can receive a Moderna or J&J booster).

The U.S. Department of Health & Human Services has announced that the U.S. will offer booster shots at no charge beginning the week of Sept. 20, 2021. The government will also directly distribute booster shots to nursing home facilities. Boosters will also be available at pharmacies, doctors’ offices, and mass vaccination sites.

CDC director Dr. Rochelle Walensky said, “These recommendations are another example of our fundamental commitment to protect as many people as possible from COVID-19. The evidence shows that all three COVID-19 vaccines authorized in the United States are safe—as demonstrated by the over 400 million vaccine doses already given. And, they are all highly effective in reducing the risk of severe disease, hospitalization, and death, even in the midst of the widely circulating Delta variant.”

Why are booster shots necessary?

Eight top U.S. public officials released a joint statement saying that based on current data, the protection provided by the COVID-19 vaccines “begins to decrease over time following the initial doses of vaccination.” And because the Delta variant causes more infections and spreads faster than earlier forms of the COVID-19 virus, U.S. public health officials say that the current vaccines are not as effective in protecting against those variants, which is why they’re recommending a booster shot. 

With efforts to distribute booster shots currently underway, the U.S. is following the lead of Israel, who started administering third shots to seniors over 60 in July. According to a study released by the Israeli government, the booster shots have effectively curtailed the Delta variant of COVID-19. 

Does this mean that the current COVID-19 vaccines are not working?

According to the CDC, the answer is no. The current COVID vaccines are ​​”working very well to prevent severe illness, hospitalization, and death, even against the widely circulating Delta variant.” 

Yale Medicine, which is affiliated with Yale University, said that vaccine efficacy waning over time is natural and that “protection [still] remains high for six months.”

Dr. Albert Shaw, a Yale Medicine infectious disease specialist, said that while a booster shot is a good strategy for maintaining high protection against COVID-19, another important strategy is to encourage those who are unvaccinated to become vaccinated. More people becoming vaccinated will prevent the spread of COVID-19 and prevent new, more infectious variants of COVID-19 from emerging. “Ultimately, [vaccinations] is what needs to be done to end the pandemic,” said Shaw.

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Viet Fact Check has partnered with a number of community and health organizations to educate the Vietnamese-American community on the COVID-19 vaccine. The project is supported by: Progressive Vietnamese American Organization (PIVOT), Asian Health Services (AHS), the California Healthy Nail Salon Collaborative, Union of North American Vietnamese American Students (UNAVSA), Southeast Asian Resource Action Center (SEARAC), Asian American Research Center on Health (ARCH) and the Association of Asian Pacific Community Health Organizations (AAPCHO).

This article is supported by the Centers for Disease Control and Prevention of the U.S. Department of Health and Human Services (HHS) as part of a financial assistance award totaling $3,300,000 with 40% funded by CDC/HHS. The contents are those of the author(s) and do not necessarily represent the official views of, nor an endorsement, by CDC/HHS, or the U.S. Government.