The Israeli Health Ministry is evaluating cases of heart inflammation in people in Israel who have received Pfizer/BioNTech’s experimental messenger RNA (mRNA) BNT162b2 vaccine for COVID-19. In a preliminary study, led by Dror Mevorach, MD head of one of the COVID-19 units at Hadassah Hospital Ein Kerem in Jerusalem, 62 cases of myocarditis—inflammation of the heart muscle (myocardium)—were identified following vaccination with BNT162b2, said the country’s National Coronavirus Project Coordinator, Nachman Ash.1 2 3 4
Cases of Myocarditis Reported Mostly After Second Dose
Most of the cases of myocarditis that have been reported in Israel are in people up to 30 years of age. Fifty-six of the cases occurred within days after administration of the second dose of the vaccine. According to Ash:
“There is specific concern regarding the frequency of the occurrence observed in men under 30 in the days immediately after the second shot,” noted the study researchers. “At this stage, according to initial findings that still need to be verified, there is an impression that the number (of cases) is higher than would be expected, especially for those under 30.”3
A Pfizer spokesperson said:
Adverse events are regularly and thoroughly reviewed and we have not observed a higher rate of myocarditis than what would be expected in the general population. A causal link to the vaccine has not been established. There is no evidence at this time to conclude that myocarditis is a risk associated with the use of Pfizer/BioNTech COVID-19 vaccine.1 5
BioNTech is reportedly looking into heart inflammation cases in Israel, but it has, so far, not found any data that would indicate a higher the normal risk of this condition with its vaccine. “We take everything we hear very seriously,” said BioNTech CEO Ugur Sahin. “The most important principle in drug development is to do no harm.”6
Myocarditis Has Multiple Causes
Identifying a causal link between myocarditis and BNT162b2 would be difficult, said Ash. The condition can be caused any number of viruses, including the Epstein-Barr virus and sexually transmitted infections such as Hepatitis C, Herpes, and Chlamydia. Certain bacteria, as well as parasites and fungal infections, can also cause myocarditis, as can certain parasites and fungal infections. Myocarditis can also be caused by reactions to drugs or can be part of uncontrolled inflammation in the body.6 7 8
Symptoms of myocarditis may include chest pain, fatigue, shortness of breath and arrhythmias. According to the Mayo Clinic, “Severe myocarditis weakens your heart so that the rest of your body doesn’t get enough blood. Clots can form in your heart, leading to a stroke or heart attack.”8
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Click here to view References:
1 Reuters. Israel examining heart inflammation cases in people who received Pfizer COVID shot. Reuters Apr. 25, 2021.
2 Odenheimer A. Israel Examines Heart Inflammation Cases After Pfizer Shot. Bloomberg Apr. 26, 2021.
3 TOI Staff. Israel said probing link between Pfizer shot and heart problem in men under 30. The Times of Israel Apr. 23, 2021.
4 JNS. Nachman Ash appointed Israel’s new Coronavirus Project Coordinator. Jewish News Syndicate Oct. 27, 2021.
5 Pharmaceutical Technology. Israel assesses myocarditis cases linked to Pfizer-BioNTech Covid-19 vaccine. Apr. 26, 2021.
6 TRT World. BioNTech probes reports of heart inflammation from Pfizer shot. Apr. 28, 2021.
7 Browne E. What Is Myocarditis? Heart Inflammation in Some Pfizer Vaccine Patients Probed in Israel. Newsweek Apr. 26, 2021.
8 Mayo Clinic. Myocarditis.