What to know about COVID-19 vaccines

Updated August 29, 2024.

Clinical Editors: Megan Dodson, PA-C, Spencer Blackman, MD, Will Kimbrough, MD

One Medical supports vaccination as an important measure to reduce the spread and harm from COVID-19, and we want you to have the most updated vaccine information.

Here are our answers to some of your most commonly asked questions:

Here are the recommendations for additional doses of Pfizer/Moderna COVID-19 vaccines based on age and the type of vaccine that was given in the initial round of vaccination:

Additional guidance

People with immunocompromising conditions:

People with immunocompromising conditions may get one or more additional doses of the COVID-19 vaccine.

Ages 65+:

People 65 years and older should get one additional dose six months after their first dose.

The Pfizer/BioNTech and Moderna COVID-19 vaccines, approved in December 2020, use messenger RNA (mRNA) which delivers a small genetic “message” that causes your own cells to make a protein that resembles the spike on the outer shell of the tiny COVID-19 virus. Your immune system then recognizes this protein as foreign, and produces specific antibodies and specialized immune cells (T-lymphocytes and B-lymphocytes) that quickly spring into action if the virus itself shows up in the future.

The Novavax vaccine uses proteins from the COVID-19 virus to create an immune response. This is similar to how many widely used vaccines work, such as vaccines for human papillomavirus, hepatitis B and shingles. The Novavax vaccine has been updated with a new formulation for 2024-2025; the number and timing of additional doses depends on which COVID-19 vaccines an individual has received in the past, and the timing of those previous vaccines.

COVID-19 vaccines have been shown to be highly effective in preventing severe illness and death from COVID-19. We’ve also learned that this protection fades over time, especially for people who are older or who have health conditions that affect their immune system.

The vaccines are administered the same way as the flu shot, injected into the muscle of the upper arm.

Common side effects may include pain around the area of the injection, feeling tired, headache, muscle aches, and less commonly, fever. So far, severe side effects have been reported to be very rare with these current COVID-19 vaccines. As with all vaccines, there have been rare reports of serious allergic reactions to the vaccine. If you've ever had a severe allergic reaction or anaphylaxis to any ingredient in either of the COVID-19 vaccines, it is not considered safe to get that specific vaccine. If you have a history of severe allergic reactions, please speak to your healthcare provider for guidance before being vaccinated.

Inflammation of the heart muscle (myocarditis) is another possible side effect that is associated with the mRNA vaccines (Pfizer and Moderna). Adolescent and young adult males have experienced higher rates of myocarditis compared to other groups, but overall, it's not common. Please check out the CDC site about myocarditis and talk to your healthcare provider for more information.

According to the CDC, “Updated COVID-19 vaccines are available to most adults living in the U.S. at no cost through their private health insurance, Medicare, and Medicaid plans.”

Yes. All authorized or approved COVID-19 vaccines can be given alongside other approved immunizations (like flu or pneumonia shots).

Adolescent or young adult males may consider waiting 4 weeks after JYNNEOS™ vaccination before getting an mRNA COVID-19 vaccine to reduce the risk of myocarditis (inflammation of the heart). However, it’s not necessary to delay monkeypox vaccination should you need it after your COVID-19 booster. If you’re not sure about the timing, talk with your healthcare provider.

Yes. While the vaccines are highly effective at preventing complications from COVID-19, they only modestly reduce your risk of infection. If you have symptoms consistent with COVID-19, we recommend getting tested to determine if your symptoms are being caused by COVID-19. Even if you test negative, consider avoiding crowds or people who are high-risk for COVID-19 complications until you’re feeling better.

Yes. Even if you’ve had a COVID-19 infection, it's still possible to get infected again.Vaccination will help prevent complications in the event of future infections.

People with a current COVID-19 infection should defer the vaccine until they have recovered from acute illness and can discontinue isolation. They may also consider waiting 3 months post-infection to get the vaccine.

No. Per the CDC, the COVID-19 vaccine cannot cause you to falsely test positive or negative on PCR or antigen viral tests, which are used to see if you have a current infection.

COVID-19 vaccination is recommended for people who are pregnant, breastfeeding, trying to get pregnant, or might become pregnant in the future. Pregnant and recently pregnant people are more likely to get severely ill with COVID-19 compared with non-pregnant people. Getting a COVID-19 vaccine can protect you from severe illness from COVID-19. If you have questions, you should talk to your provider to make an informed decision for your unique situation. More information about pregnancy and the vaccine is available here

If your child is 6 months or older, they're eligible to receive the Pfizer/BioNTech or Moderna COVID-19 vaccine. The CDC now considers it safe to receive the COVID-19 vaccine at the same time as other recommended vaccines. For more information on COVID-19 vaccines for children, see here.