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Seven boys between the ages of 14 and 19 in the U.S. reportedly developed chest pain and heart inflammation within four days of receiving a second dose of the Pfizer/BioNTech COVID vaccine, according to a new study published today in Pediatrics.

Heart imaging tests detected a rare type of heart muscle inflammation called myocarditis and pericarditis. None of the teens were critically ill but all were hospitalized.

All were healthy enough to be sent home after two to six days in the hospital and are ‘’doing pretty well,’’ said Dr. Preeti Jaggi, an Emory University infectious disease specialist who co-authored the report.

Jaggi said more follow-up is needed to determine how the seven fare, but it’s likely the heart changes were temporary.

Only one of the seven boys in the Pediatrics report displayed evidence of a possible previous COVID infection, and doctors determined none of them had a rare inflammatory condition linked with COVID or pre-existing conditions.

“I think we’re in the waiting period where we need to see whether this is cause-and-effect or not,” said John Grabenstein of the Immunization Action Coalition, a former director of the U.S. Department of Defense’s immunization program.

It is possible myocarditis or pericarditis may be an additional rare adverse event related to systemic reactogenicity, but currently no causal association has been established between this vaccine and myopericarditis, the authors concluded.

Myocarditis is inflammation of the heart muscle that can lead to cardiac arrhythmia and death. According to researchers at the National Organization for Rare Disorders, myocarditis can result from infections, but “more commonly the myocarditis is a result of the body’s immune reaction to the initial heart damage.”

Pericarditis is often used interchangeably with myocarditis and refers to inflammation of the pericardium, the thin sac surrounding the heart.

A search in the Vaccine Adverse Events Reporting System (VAERS) revealed 628 cases of myocarditis and pericarditis, among all age groups reported in the U.S following COVID vaccination between Dec.14, 2020 and May 28, 2021. Of the 628 cases reported, 392 cases were attributed to Pfizer, 206 cases to Moderna and 27 cases to J&J’s COVID vaccine.

Of the 628 total cases of heart inflammation reported to VAERS, 40 cases occurred in children ages 12 to 17, all were attributed to Pfizer’s vaccine.

The U.S., Europe and Israel have all announced they are investigating a possible link between heart inflammation and mRNA vaccines, like Pfizer and Moderna.

On June 2, Israeli health officials announced they had found a “probable” link between Pfizer’s vaccine — which the country has relied on almost exclusively in its vaccination drive — and dozens of cases of heart inflammation in young men following the second dose.

According to a study by Israeli health officials, there were 275 cases of myocarditis identified in Israel between December 2020 and May 2021, including 148 cases that occurred within a month after vaccination. Of those 148 cases, 27 occurred after the first dose and 121 after the second dose. About half of the cases involved people with previous medical conditions.

Many of the cases were reported among men 16 to 30, and most often in 16- to 19-year-olds. Most of the patients were discharged from the hospital in less than four days, and 95% of the cases were considered mild.

“There is a likelihood of a connection between receiving a second dose of vaccine and the onset of myocarditis in young men aged 16-30,” the group of experts concluded. “The connection is stronger in young people aged 16-19 compared to other ages and it decreases as age increases.”

As The Defender reported May 10, EU regulators called on Pfizer and Moderna to provide additional data related to the companies’ COVID vaccines and a potential link to heart inflammation after the agency completed a safety review of all four COVID vaccines authorized for emergency use in the EU.

In a report issued May 7, the European Medicines Agency’s safety committee, (PRAC), disclosed its members were aware of cases of myocarditis and pericarditis following Pfizer vaccination.

As a prevention, PRAC requested Pfizer provide further data, including an analysis of events according to age and gender, in its next pandemic summary safety report before regulators could determine if any other regulatory action is needed.

On May 24, the Centers for Disease Control and Prevention (CDC) announced it was investigating reports that some teenagers and young adults vaccinated against COVID may have experienced heart problems.

The CDC’s Advisory Committee on Immunization Practices in a May 17 statement said reports of myocarditis to date seemed to occur predominantly in adolescents and young adults, more often in males than females, more often following the second dose and typically within four days after vaccination. Most cases appeared to be “mild” and follow-up is ongoing.

On April 27, Reuters reported the U.S. Department of Defense was investigating 14 cases of heart inflammation among people who were vaccinated through the military’s health services.