COVID-19 Vaccine Boosters for Those With Underlying Medical Conditions

COVID-19 vaccines continue to be highly effective at preventing severe illness, hospitalization, and death due to COVID-19, including from the Delta variant. But protection appears to decrease over time, and people with underlying medical conditions are at increased risk of severe illness from COVID-19. As a result, some people are now eligible for a booster shot.

Who Is Eligible for a Booster

You’re eligible to get a booster shot if:

  • It's been at least 6 months since you got the second dose of a Pfizer-BioTech or Moderna vaccine;
  • You're at least 18 years old; and 

  • You're at increased risk for severe COVID-19 because of an underlying medical condition. 

Such conditions include:

  • Cancer
  • Chronic kidney disease
  • Chronic lung diseases, including COPD (chronic obstructive pulmonary disease), asthma, interstitial lung disease, cystic fibrosis, and pulmonary hypertension
  • Dementia or other neurological conditions
  • Type 1 or 2 diabetes
  • Down syndrome
  • Heart conditions, such as heart failure, coronary artery disease, cardiomyopathies or hypertension
  • HIV infection
  • Liver disease
  • Overweight and obesity
  • Pregnancy
  • Sickle cell disease or thalassemia
  • Smoking, current or former
  • Solid organ or blood stem cell transplant
  • Stroke or cerebrovascular disease, which affects blood flow to the brain
  • Substance use disorders

If you have a condition that is not listed above, your health care provider can help you decide if a booster is right for you.

CDC recommends that all individuals who are at least 18 years old and who got Johnson & Johnson’s Janssen vaccine—regardless of whether you have an underlying medical condition—get a booster at least 2 months after your first dose.

If you're eligible for a booster, you may choose which vaccine to receive as a booster dose. Your booster shot doesn't have to be the same vaccine you received before. 

For more information about boosters, or if you have questions about your eligibility, visit or talk to a health care provider. 

How to Find Vaccines

You have three ways to find vaccines near you:

  • Go to
  • Text your ZIP code to 438829
  • Call 1-800-232-0233