The Washington State Department of Health (DOH) is aware of reports of a small number of cases of myocarditis or pericarditis in some patients, post-vaccination. Further investigation is needed to determine if these cases are connected in any way to COVID-19 vaccines.
Health care providers in Washington, Idaho and Oregon have been notified about this issue so they can be ready to quickly identify symptoms if more cases occur.
Myocarditis is an inflammation of the heart tissue, and is usually caused by a viral infection. Symptoms include chest pain, abnormal heartbeat, and shortness of breath. Pericarditis is swelling and irritation of the thin, saclike tissue surrounding the heart.
DOH is working with the Centers for Disease Control and Prevention (CDC), local public health, and healthcare providers in our state to gather data and other information about these incidents.
[EDITOR’S NOTE: Other reports online indicate this is not a new finding, having been under investigation since last summer, and has been observed in young people receiving vaccines.]
US investigating handful of myocarditis cases following COVID-19 vaccination
There may not be any link, as the condition is somewhat common.
A U.S. vaccine safety working group is looking into a small number of cases of heart inflammation in young people following COVID-19 vaccines, Reuters reported. Most cases reported so far have been mild.
The condition, called myocarditis, is also somewhat common, and the rate seen so far in vaccinated people does not differ from the baseline expected in the population, meaning there may be no link.
And even if a link can be established, “vaccines are going to unequivocally be much more beneficial outweighing this very low, if conclusively established, risk,” Dr. Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security, told Reuters, referring to the immense benefit the vaccine provides in preventing a COVID-19 infection.
To see whether there is a link, the researchers are reviewing records and asking clinicians to be on the alert to report such cases.
Myocarditis is an inflammation of the heart muscle that often occurs after infection with a virus, such as influenza or the novel coronavirus that causes COVID-19. Symptoms can range from mild fatigue and chest pain that resolves on its own to heart rhythm irregularities, cardiac arrest and even death in rare, severe cases. Most cases resolve with no long-term effects, according to a 2020 review in the Journal of Cardiothoracic and Vascular Anesthesia. Males tend to be more commonly affected by myocarditis, according to that study.
About 10 to 22 people per 100,000 — or up to 70,000 people in the U.S. — are diagnosed with viral myocarditis every year, according to the study. However, many cases are so mild that they are never diagnosed, meaning true incidence is likely higher.
So far, more than 4 million people under age 18 have received mRNA COVID-19 vaccines, and tens of millions ages 24 and younger have received the vaccine, according to the CDC, so many cases would be expected by chance in this population. The CDC did not say how many cases of myocarditis they were investigating.
