With increased FDA authorization of boosters and additional COVID-19 vaccine shots for eligible patients, it’s important to know the difference between the purposes of these shots to make the most informed decision about your care. Experts from Johns Hopkins University explain the differences in application between boosters and regular additional vaccines. 

What Is the Purpose of a COVID Booster?

COVID boosters are additional shots of the COVID-19 vaccine, but they’re given for prevention in patients with healthy immune systems. The booster is designed to help people maintain their level of immunity for longer periods of time. It is best reserved for healthy or asymptomatic patients who are six months (Moderna or Pfizer) or two months (Johnson & Johnson) removed from their last vaccine dose. 

What Is the Purpose of an Additional Regular COVID Vaccine Shot?

Third and subsequent COVID-19 vaccinations are also given to people with moderately or severely compromised immune systems to improve their response to the initial vaccines. Some patients who may be eligible for additional doses before the booster window include: 

• Those receiving active treatment for tumors or blood cancer
• Organ transplant recipients currently taking immunosuppressants
• Those who have undergone stem cell surgery within the last two years
• People diagnosed with moderate or severe primary immunodeficiency (such as DiGeorge syndrome or Wiskott-Aldrich syndrome)
• HIV patients with a high viral load or low CD4 count, or those not currently taking medication to treat HIV
• Those taking drugs like high-dose steroids or other medications that may cause severe suppression of the immune system

Details for eligibility will vary depending on your overall health and your care needs. Speak to your doctor to determine if you should get an additional shot before your booster window. 

Can I Get A COVID Booster?

While eligibility is increasing on a regular basis, the Centers for Disease Control and Prevention (CDC) currently offers the following guidelines: 

Pfizer or Moderna – Six Months after Last Vaccine 

• 65 years or older
• Age 18 or older who live in long-term care settings
• Age 18 or older who have underlying medical conditions
• Age 18 or older who work or live in high-risk settings

Johnson & Johnson’s Janssen – Two Months after Last Vaccine

• 18 years of age or older

You can now mix-and-match your combination of boosters and initial vaccines based on preference and availability of doses. 

*Maragakis, Lisa, M.D., M.P.H. and Kelen, Gabor David, M.D. (09, November 2021) Booster Shots, Third Doses and Additional Doses for COVID-19 Vaccines: What You Need to Know

Much about the novel coronavirus, i.e., COVID-19, is still not fully understood. As research progresses and our knowledge of the virus increases, information can change rapidly. We strive to update all of our articles as quickly as possible, but there may occasionally be some lag between scientific developments and our revisions.