COVID-19 boosters are in the news right now after approvals from the FDA and CDC. It is natural to wonder what to do next. What does the booster do? Who should get it? Which one? So, here are answers to some of the most common questions about boosters I am seeing now.
1. What are COVID-19 vaccine booster doses?
Initially there was data to support additional doses of the vaccines in immunocompromised individuals whose immune systems did not respond strongly enough to the initial vaccine series. The additional dose helped achieve immunity similar to people without an immunocompromising condition. However, we now have data that even a normal immune response to the initial vaccines slowly fades over time. This waning immunity can be “boosted” with an additional shot, called a booster vaccination.
Although all three vaccines continue to provide very good protection against serious COVID-19 infections that result in hospitalizations or death, there is concern that older individuals and younger individuals with chronic medical conditions may not be as well protected over time. Booster doses help to restore strong protection against COVID-19, even for infections caused by the coronavirus variants. In this case, a COVID-19 booster is a third dose of either the Pfizer or Moderna vaccines, or a second dose of the Johnson & Johnson vaccine.
2. Who should receive a COVID-19 booster dose?
For the Pfizer and Moderna vaccines, a third (booster) dose is recommended for adults aged 65 years and older, any adult who lives in a long-term care facility and adults with underlying medical conditions that put them at increased risk of COVID-19 complications such as chronic kidney disease, high blood pressure, dementia, diabetes, chronic lung disease and cancer. In addition, the CDC is recommending a third dose of the Pfizer and Moderna vaccines for adults who are at increased risk of exposure and transmission of the coronavirus due to their occupation or setting in which they work or live. This includes first responders, healthcare workers, teachers, and other frontline workers in our communities.
The third dose of the Pfizer and Moderna boosters should be given at 6 or more months after the second dose. Adults who received one dose of the Johnson & Johnson vaccine should receive a second (booster) dose two or more months after the first dose.
3. Can COVID-19 vaccines be mixed, or should I receive the same vaccine for a booster dose?
The FDA has approved “mixing” of vaccines for booster doses. This means that you have the option of receiving a vaccine from a different manufacturer for your booster dose. In general, you may want to get the same vaccine that you originally received, but this approval for vaccine interchange provides much more flexibility when getting your booster dose. Easy availability of a particular vaccine might influence your decision. There is some evidence that for individuals who received the Johnson & Johnson vaccine, a stronger antibody response was observed if Pfizer or Moderna was used as the booster vaccine. You should talk to your doctor if you have questions about which vaccine booster is right for you.
4. If I need a booster dose, does that mean that the COVID-19 vaccine is not working?
No, booster doses do not imply that the COVID-19 vaccines are not working. COVID-19 vaccines continue to protect us very well from severe illness, hospitalization, and death caused by COVID-19, including illness caused by the Delta variant. However, the vaccine protection slowly decreases over time, especially for older adults. A booster dose serves as a refresher course for the immune system to help restore high levels of antibodies against the coronavirus infection. It is not unusual to need booster doses for other vaccines. Many childhood vaccination require a series of vaccines. Adults routinely receive boosters for tetanus and pertussis.
5. What are the side effects from a COVID-19 vaccine booster shots?
Fortunately, the side effects after a booster dose of a COVID-19 vaccine are no worse than the initial vaccine or vaccine series. Pain, redness, and swelling at the injection site are common local reactions. Adults also can develop low-grade fever, chills, muscle aches, and fatigue. Fortunately, these side effects are generally mild and typically go away in about a day or two. Serious reactions to the COVID-19 vaccines, even after booster doses, remain extremely rare. If you had mild to moderate side effects from your previous COVID-19 vaccine, you would likely have a similar experience with a booster dose. Remember that many of these local reactions and systemic side effects are signals that your body is responding to the vaccine and developing a stronger immune response.
6. Will I need more doses of the COVID-19 vaccine in the future?
It can be frustrating to repeatedly get vaccinated for COVID-19, but vaccination is important to protect your health and and the health of those around you. We are dealing with a new virus that changes, so we are learning a lot about the vaccines over time. There are ongoing clinical trials that continue to monitor protection from COVID-19 and the immune response after vaccination. It is impossible to know at this point if more vaccine doses will be needed in the future, but we will continue to learn. Current evidence suggests that there is a very strong immune response after booster doses and the hope is that antibody levels remain high for a much longer time than after the initial vaccine or vaccine series.
It is important to remember that other infectious disease, like influenza, require vaccination on an annual basis. We may need additional doses of the COVID-19 vaccine in the future, but only time will tell.
7. Will the booster help protect me from the coronavirus variants?
All three vaccines continue to show good protection from the coronavirus variants, including the Delta variant. However, the protection is not as strong as the protection against the original coronavirus that caused COVID-19. Booster doses have been shown to increase antibody levels greatly, and it appears that higher levels of antibodies provide even better protection against the coronavirus variants.
8. Should I get both an influenza vaccine and COVID-19 vaccine?
Yes! Although rates of influenza were very low last year when mask wearing and physical distancing limited spread of many respiratory viruses, the influenza virus continued to circulate and is expected to cause illness during this next flu season. Since influenza can cause serious illness and death for older adults, annual vaccination is very important. Influenza vaccines (flu shots) are widely available across the country and are strongly recommended.
It is safe to receive the influenza and COVID-19 vaccines at the same time at different sites (such as opposite arms), although you or your doctor might decide that separating the vaccines by a few days or week is a better plan for you. Just make sure you are vaccinated for both influenza and COVID-19 this year. Ideally, influenza vaccination should occur by the end of October, but you can receive the vaccine at any time when the influenza vaccine is available.
9. If I do not get a booster dose, am I still considered fully vaccinated?
Yes, you are considered fully vaccinated two weeks after receiving two doses of the Pfizer or Moderna vaccine or one dose of the Johnson & Johnson vaccine for COVID-19. However, if you belong to one of the higher risk groups for COVID-19 complications, including older adults aged 65 years or older, an adult resident of a long-term care facility or you have one or more chronic medical conditions then you should strongly consider getting a booster dose of a COVID-19 vaccine in order to maximize your protection. Booster doses should be 6 or more months after your second dose of Pfizer or Moderna and two or more months after the initial Johnson & Johnson vaccine.
10. Should we be recommending booster doses when there are still so many people who have not been vaccinated for COVID-19?
Booster doses of the COVID-19 vaccine are especially important to protect individuals at increased risk of complications from COVID-19, including older adults, nursing home residents, and those with significant underlying chronic medical conditions. Since the vaccine supply in the United States is sufficient, it is appropriate to recommend boosters. However, it is worrisome that many eligible Americans have not been vaccinated. We now have ample evidence that the COVID-19 vaccines are safe and effective. We should continue efforts to increase the vaccination rates for eligible individuals, since high rates of vaccination are essentially the only way out of this pandemic and our best defense against the emergence of future coronavirus variants.Anthony J. Caprio, MD, is medical director at The Sharon at SouthPark and geriatrician at Atrium Health. The opinions expressed by Dr. Caprio in this article are his own and not necessarily those of Atrium Health.
