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Who Should Get a COVID-19 Booster Shot?

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, 4 min read

Who Should Get a COVID-19 Booster Shot?

This page is reviewed regularly. Last updated on October 4, 2021.

Scientists continue to research the COVID-19 virus and its response to vaccines. Every day they’re learning more about the best ways to fight it.

Recently, the U.S. Food and Drug Administration authorized a booster dose for some people. 1 You may get a booster dose if you finished your first series of the Pfizer-BioNTech vaccine at least six months ago and are:

  • Age 65 or older
  • Age 18 or older and have underlying medical conditions or live or work in a high-risk setting
  • Moderately to severely immunocompromised 2

We’ll know more soon

If you’re not in one of these groups, sit tight. As they learn more, public health experts may recommend boosters for more people. Boosters from Moderna and Johnson & Johnson are going through their own approval process. More information will be available soon.

Why are boosters needed?

Like with any vaccine, protection against COVID-19 may decrease over time. Right now, the Delta variant is spreading more quickly than earlier strains of the virus. Vaccination still prevents severe disease, but breakthrough infections with milder symptoms are possible.

How does a booster dose work?

A booster is another dose of a vaccine you received. Over time, your immune system’s “memory” can fade. Another dose of the vaccine can increase the numbers of your immune system’s “memory” cells. Then, your immune system can react more strongly to fight against COVID-19 infection.

The bigger picture

Booster shots can help prevent the spread of COVID-19. Slowing the spread reduces the chances that new variants will develop. New variants could cause more severe disease. Variants also have the potential to get around the protection of current vaccines. It’s still unknown if we’ll need boosters every year or two, or if one more dose will be enough for long-term protection.

What are the side effects?

You might have pain, redness or swelling in your arm where you get the shot. Other side effects may include tiredness, headache, muscle pain, chills, fever and nausea. Side effects happen within a day or two of getting your booster. They are normal signs that your immune system is working and side effects should go away within a few days. Most side effects are mild to moderate and serious side effects are rare.

Should I wait so that someone else can get my dose?

Delaying a booster shot does not mean your dose will go to someone in need. Vaccines are now widely available in the US. Delivering vaccines in low-income countries is difficult and requires coordinated efforts. There are programs in place to donate vaccines where they’re needed. Getting your booster is one way you can help control the spread of COVID-19.

Finding your dose

The effectiveness of the Pfizer-BioNTech vaccine decreases gradually over time. You don’t have to rush, but make a plan to get a booster soon if you’re eligible.

Visit to find a pharmacy location near you with doses in stock ( en Español). You can also text your ZIP code to 438829. And you can always call the National Vaccine Hotline at 1-800-232-0233.

Your local pharmacy chain, like Walgreens, Walmart or CVS, offers easy access. Many pharmacies have walk-in appointments, but it may be easier to schedule ahead of time.

You may also be able to get a booster at a vaccination site run by your state or county health department. Check out the Babylon vaccine page to see how your local agencies are providing vaccines.

Is there a cost?

Health insurance companies cover the cost of the vaccine. You may be asked for your insurance information when you book your appointment. If you don’t have insurance, you will not have to pay.

You do not need a driver’s license to receive a shot, but if you can, bring some form of ID. This is so that vaccinators can be reimbursed for your dose of the vaccine.

Boosters are one tool in our pandemic toolbox

How can you help bring COVID-19 under control? Keep up with vaccinations and booster doses, practice social distancing, wear a mask and wash your hands.


1. CDC: Statement on ACIP Booster Recommendations

2. CDC: COVID-19 Vaccines for Moderately to Severely Immunocompromised People

The information provided is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Seek the advice of a doctor with any questions you may have regarding a medical condition. Never delay seeking or disregard professional medical advice because of something you have read here.

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