What's the difference between a third shot and a COVID-19 booster?

Posted at 3:10 PM, Oct 17, 2021

(WXYZ) — There are many places to get the COVID-19 vaccine: the Detroit Health Department will come to you, the TCF Center has been a hub for administering it, including the booster shot. But there is also a third dose option.


And experts are saying it's important to know the difference.

"I was ready for it. After I had the first two shots, and I had no problems. No complications whatsoever, I mean what do you have to lose," said Audrey Lasalle Brown.

Audrey and her friend Gloria W. Jackson carpooled to get the COVID vaccine booster shot at the TCF Center on Monday.

"We called earlier, and we were not allowed unless we had some underlying condition. And so we waited," said Jackson.

The two waited until the booster shot became available for people over 65. That age group, along with people who work in occupations at high risk of exposure to COVID, are eligible for the booster.

"The difference between a third shot and a booster shot is related to the type of people who are taking the vaccine," said Dr. Iris Taylor, nursing director with the Detroit Health Department.

The Detroit Health Department is working to clear up confusion over the two categories. Dr. Taylor explains the third shot is otherwise known as an "additional dose."

"So that third shot is for that population of people who are immunocompromised, who have had cancer, who've taken high doses of steroids, who've had organ transplants, or who've taken medications that could have a negative impact on your immune system," said Dr. Taylor.

The other difference between the two categories are the times you must wait to get the extra shot.

The Michigan Department of Health and Human Services tweeted an infographic, laying it out.

It shows the booster shot is currently limited to recipients who originally got the Pfizer vaccine. The third shot or additional dose is only available via Pfizer and Moderna for the immunocomprised, like Delorise Williams.

"Ya know, it's too many people dying man," said Williams.

As for those looking to get the Moderna or Johnson & Johnson booster, or the J&J third dose, Dr. Taylor says, "we need you to just be patient."

COVID booster FAQs from the Centers for Disease Control and Prevention:

When can I get a COVID-19 vaccine booster if I am NOT in one of the recommended groups?

Additional populations may be recommended to receive a booster shot as more data become available. The COVID-19 vaccines approved and authorized in the United States continue to be effective at reducing risk of severe disease, hospitalization, and death. Experts are looking at all available data to understand how well the vaccines are working for different populations. This includes looking at how new variants, like Delta, affect vaccine effectiveness.

What should people who received Moderna or Johnson & Johnson’s Janssen (J&J/Janssen) vaccine do?

The Advisory Committee on Immunization Practices (ACIP) and CDC’s recommendations are bound by what the U.S. Food and Drug Administration’s (FDA) authorizationexternal icon allows. At this time, the Pfizer-BioNTech booster authorization only applies to people whose primary series was Pfizer-BioNTech vaccine. People in the recommended groups who got the Moderna or J&J/Janssen vaccine will likely need a booster shot. More data on the effectiveness and safety of Moderna and J&J/Janssen booster shots are expected soon. With those data in hand, CDC will keep the public informed with a timely plan for Moderna and J&J/Janssen booster shots.

If we need a booster shot, does that mean that the vaccines aren’t working?

No. COVID-19 vaccines are working well to prevent severe illness, hospitalization, and death, even against the widely circulating Delta variant. However, public health experts are starting to see reduced protection, especially among certain populations, against mild and moderate disease.

What are the risks to getting a booster shot?

So far, reactions reported pdf icon[4.7 MB, 88 pages] after getting the Pfizer-BioNTech booster shot were similar to that of the 2-shot primary series. Fatigue and pain at the injection site were the most commonly reported side effects, and overall, most side effects were mild to moderate. However, as with the 2-shot primary series, serious side effects are rare, but may occur.

Am I still considered “fully vaccinated” if I don’t get a booster shot?

Yes. Everyone is still considered fully vaccinated two weeks after their second dose in a 2-shot series, such as the Pfizer-BioNTech or Moderna vaccines, or two weeks after a single-dose vaccine, such as the J&J/Janssen vaccine.