Seven teenage boys in the US developed heart inflammation after second dose of COVID vaccine and were taken to hospital, study reveals

• A study of seven U.S. teen boys in several states reported having a heart inflammation after the second COVID vaccine 
• The boys in the study, ages 14 to 19, developed chest pain within a few days of their second Pfizer dose
• None of the boys were critically ill and were sent home from the hospital within two to six days
• The study comes as the Israeli Ministry of Health, the European Medicines Agency, the Department of Defense and the CDC study the potential link
• The heart muscle inflammation, known as myocarditis, can be a side effect of different viruses 

Health authorities are trying to determine whether heart inflammation that can occur as a result of many different types of infections could also be a rare side effect in teens and young adults after the second dose of COVID-19 vaccine.

An article on seven U.S. teen boys in several states, published online Friday in Pediatrics, is among the latest reports of young men getting heart inflammation after their second COVID-19 vaccination, though a link to the vaccine has not been proven.

The boys in the study, between the ages of 14 and 19, received Pfizer shots in April or May and developed chest pain within a few days. Heart imaging tests showed a type of heart muscle inflammation called myocarditis.

None were critically ill, and all were healthy enough to be sent home after two to six days in the hospital. They are all 'doing pretty well,' according to Dr. Preeti Jaggi, an Emory University infectious disease specialist who co-authored the report.

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

Only one of the seven boys in the Pediatrics report had evidence of a possible previous COVID-19 infection, and doctors determined none of them had a rare inflammatory condition linked with the coronavirus.

The cases echo reports from Israel in young men diagnosed after receiving Pfizer shots.

The Israeli Ministry of Health concluded on June 1 that between one in 3,000 to one in 6,000 men ages 16 to 24 who received the vaccine developed the rare condition.

Israeli health officials first flagged the issue in April when they reported more than 60 cases.

Around the same time, the Department of Defense began to track 14 cases, and officials at the European Medicines Agency said on May 28 they received 107 reports of myocarditis following the Pfizer vaccine. That amounts to one young man receiving the rare heart disease in 175,000 doses administered.

The U.S. Centers for Disease Control and Prevention also alerted doctors last month that it was monitoring a small number of reports of heart inflammation in teens and young adults after the mRNA vaccines, the kind made by Pfizer and Moderna.

The CDC hasn´t determined if there´s really a link to the shots, and continues to urge that everyone 12 and older get vaccinated against COVID-19, which is far riskier than the vaccine. 

The Pfizer vaccine is available to those as young as 12; the Moderna shot remains cleared only for adult use.

This kind of heart inflammation can be caused by a variety of infections, including a bout of COVID-19, as well as certain medications — and there have been rare reports following other types of vaccinations.

Authorities will have to tease out whether cases following COVID-19 vaccination are occurring more often than that expected 'background rate.'

For now, the CDC says most patients were male, reported symptoms after the second dose, and their symptoms rapidly improved.

'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 Defense Department´s immunization program.

A Pediatrics editorial noted that among U.S. children under age 18, there have been over 4 million COVID-19 cases, more than 15,000 hospitalizations and at least 300 deaths.

It said the heart inflammation cases warrant more investigation but added that ´the benefits of vaccination against this deadly and highly transmissible disease clearly far outweigh any potential risks.'