More than 102.8 million Americans had received a first booster dose as of May 23, 2022, according to the Centers for Disease Control and Prevention (CDC), and that number should be on the rise with the recent FDA and CDC recommendations. In the coming months, this change will allow millions more Americans to get additional protection.

Robert Quigley, MD, DPhil, Senior Vice President and Global Medical Director of International SOS, told Verywell that the vaccines “have been a critical part of recovering from the pandemic, and booster shots act as an extension of that momentum and protection—especially right before we enter the winter season at which time social distancing will be that much more complicated.”

The original vaccine series is still very effective at protecting people against severe COVID illness that requires hospitalization. However, boosters are recommended because data has shown that the effectiveness of the first shots can decrease over time. That means that Americans might be more vulnerable to breakthrough infections, especially as new variants of the virus emerge.

“We’ve seen that there has been an increase in infections and hospitalizations of those who are not fully vaccinated,” Quigley said. “It has been suggested that the COVID-19 vaccines lose their strength in protection over an extended period of time."

Getting a booster shot protects you and the people that you come into contact with as you go about your daily life—some of whom might need extra protection because they’re at a higher risk of getting sick or having complications if they do.

Where Can I Get a Booster?

Although each state handles its vaccine rollout differently, you should be able to find free COVID-19 booster shots at the same locations where the original series of vaccinations were offered, such as doctors’ offices, pharmacies, hospitals, schools, and community-sponsored events.

Last year, the CDC launched the website Vaccines.gov to help people find where to get vaccinated. The site allows you to search for a vaccination site by zip code, making it quick and easy to find places in your area that offer boosters by appointment or walk-in. 

You can also check your state’s website to find out where you can get a vaccine or booster. For example, California offers MyTurn, New York state offers COVID-19 Vaccine, and Florida has created the Florida COVID-19 Response website to help its citizens find a vaccination site. Your county health website may have additional information as well.

Do Boosters Have Side Effects?

The booster shots made by Pfizer, Moderna, and Johnson & Johnson all use the same formulas that were used for the primary series of shots. However, the Moderna booster shot is half the dose of the original shots.

Children and teens 5–17 years old may only get a Pfizer COVID-19 vaccine booster.

If you got the two-dose Pfizer or Moderna shots first, you need to wait five months from your second dose to get a booster. If you got the Johnson & Johnson one-shot vaccine, you can get a booster of your choice after two months.

People 12 years of age and older with certain kinds of immunocompromise and all people age 50+ who have received an initial mRNA booster dose at least four months ago are eligible for a second booster dose. 

Adults who have received a primary vaccine and booster dose of Johnson & Johnson’s vaccine at least four months ago can now receive a second booster using an mRNA COVID-19 vaccine.

You can look for appointments here.

No matter which booster you receive, it is possible to experience mild side effects similar to those you might have had after your first doses, including:

Muscle achesSoreness at the injection site FeverHeadacheFatigueNausea 

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.