CDC reports rare cases of heart inflammation in young men after mRNA COVID-19 vaccination

Vaccination efforts have rolled out in most countries starting in the last quarter of 2020 with more than 2.37 billion vaccines administered worldwide so far. However, reports of cardiac inflammation (myocarditis and pericarditis) occurring after the mRNA COVID-19 vaccination (Pfizer-BioNTech and Moderna) have increased in the United States since April 2021.

The U.S. Centers for Disease Control and Prevention (CDC) reports a higher-than-expected number of heart inflammation in young men who received their second dose of messenger RNA (mRNA) vaccine.

The report, which appeared on CDC’s website, came from two vaccine safety monitoring systems, called Vaccine Adverse Event Reporting System (VAERS) and the Vaccine Safety Datalink (VSD).

Myocarditis and Pericarditis Following mRNA COVID-19 Vaccination. Image Credit: Dr. Norbert Lange / Shutterstock

Myocarditis and Pericarditis

In the United States, more than 310 million vaccine doses have been administered. Throughout the vaccination roll-out, the CDC monitors the safety of the vaccines for any health problems arising after vaccination.

Myocarditis is the inflammation of the heart, while pericarditis is the inflammation of the pericardium, a sac-like structure with two thin layers of tissue that surround the heart to hold it in place

There were 285 observed cases of heart inflammation after the second dose in those between 16 and 24 years old in the VAERS data. The expected cases were 10 to 102 cases for the age bracket, based on U.S. population background incidence rates. These case reports had known disposition at the time of report review.

81 percent had full recovery of symptoms during the study period, while 41 had ongoing signs or symptoms.

The VSD is another safety monitoring system that reported an increased incidence of heart inflammation in people between 16 and 34 years old after their second vaccine dose compared to the rate seen after the first dose.

These reports were noted since April 2021, but the cases are rare, given the number of vaccines administered. Nevertheless, the health agency is actively monitoring the accounts through data and medical records review. This can shed light on what caused the side effect and the link between the conditions and COVID-19 vaccination.

The CDC reports that most cases were found in male adolescents and young adults 16 years old and above a few days after receiving the second dose of the vaccine.

Most of the patients responded well to treatment and rest, helping them recover faster. As a result, they can return to their normal daily activities after recovery. However, the CDC emphasized that the patients should consult with a doctor regarding return to sports or exercise.

“We clearly have an imbalance there,” Dr. Tom Shimabukuro, deputy director of the CDC’s Immunization Safety Office and CDC COVID-19 Vaccine Task Force, said in a presentation to an advisory committee to the U.S. Food and Drug Administration meeting.

The CDC will hold a meeting of its Advisory Committee on Immunization Practices to further assess the risk of myocarditis after mRNA vaccination for COVID-19.

CDC recommends COVID-19 vaccination

Still, the CDC recommends having the COVID-19 vaccination for everyone 12 years and older, given the greater risk of COVID-19 illness and its potentially severe complications. These include potential long-term health problems, hospitalization, and even death.

Receiving the vaccine is the best way to protect oneself and family members from COVID-19. The agency also emphasized that COVID-19 vaccination outweighs the potential risks, including myocarditis and pericarditis.

Along with vaccination, the health agency reiterates the importance of non-pharmaceutical measures to prevent viral transmission. These include regular hand hygiene, physical distancing, avoiding crowded places, wearing face masks, and testing.

Written by

Angela Betsaida B. Laguipo

Angela is a nurse by profession and a writer by heart. She graduated with honors (Cum Laude) for her Bachelor of Nursing degree at the University of Baguio, Philippines. She is currently completing her Master's Degree where she specialized in Maternal and Child Nursing and worked as a clinical instructor and educator in the School of Nursing at the University of Baguio.