COVID-19 vaccine: Four years later, the list of persistent symptoms grows.

Additionally, all vaccines significantly increased the risk of myocarditis and pericarditis (inflammation of the myocardium, the muscle responsible for heart contraction and blood circulation throughout the body)   . "  Other warning signs have been identified that require further investigation  ," the journal states. The researchers emphasize that further research is needed to determine the link between the vaccine and these side effects.