Rare COVID-19 Vaccine Complication Linked to Circulating Spike Protein in Blood

Young adults and adolescents that suffered from rare cases of myocarditis following vaccination with a mRNA-based COVID-19 vaccine had increased levels of the viral protein spike in their bloodstream, found a recent study carried out by a team at Brigham and Women’s Hospital and Massachusetts General Hospital. However, it also concluded that the benefits of COVID-19 vaccination still greatly outweigh the risks.

Myocarditis occurs when heart muscle tissue becomes inflamed, often resulting in chest pain and fatigue. It is observed in a number of conditions including viral infections and inflammatory diseases. In extremely rare cases—roughly one or two people per 100,000— myocarditis can result from vaccination by...