What to Know About COVID-19 Vaccines and Heart Conditions in Younger People

On June 23, a group of scientists told the U.S. Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices that mRNA vaccines (those made by Pfizer-BioNTech and Moderna) have a “likely association” with heart risks for younger people. Understandably, that’s still generating a lot of attention. Here’s what you should know about COVID-19 vaccines and heart problems.

The heart issues in question are called myocarditis and pericarditis

Those refer, respectively, to inflammation of the heart and the lining around it. While they sound scary, both tend to clear up on their own or with minimal treatment, particularly if caught early. They can come with symptoms like chest pain, shortness of breath, fatigue and abnormal heart rhythms, and can be caused by viruses and bacteria.

They are a very rare vaccine side effect

Since April, about 1,000 cases have been reported among people who got vaccinated with mRNA-based shots, the CDC says. That might sound like a lot, but, for context, more than 300 million mRNA vaccine doses have been administered so far in the U.S. A statement signed by influential physicians including CDC Director Dr. Rochelle Walensky notes that myocarditis and pericarditis are far more common among people who catch COVID-19 than among people who get the vaccine.

Certain groups seem to be at higher risk

Adolescent boys and young men seem to develop these side effects more often than other groups, according to the CDC, and it is more common after a second shot. In general—that is, separate from COVID-19 side effects—men are more likely than women to develop heart inflammation, and it is commonly diagnosed among younger adults.

Experts still recommend vaccination

Given the known benefits of COVID-19 vaccination, physicians still recommend the shots for people of all ages. “It is the best way to protect yourself, your loved ones, your community, and to return to a more normal lifestyle safely and quickly,” the group of physicians urged in their joint statement.

This story originally ran in TIME’s Coronavirus Brief newsletter.