Two recent studies conducted in Israel agree that the risk of Pfizer’s COVID-19 vaccine causing myocarditis (inflammation of the heart muscle) is extremely low.
Both investigations were published last week in the scientific journal The New England Journal of Medicine
The scientists of the study titled “Myocarditis after BNT162b2 mRNA Vaccine (Pfizer) against COVID-19 in Israel” retrospectively reviewed data obtained from December 20, 2020 to May 31, 2021 regarding all cases of myocarditis. They then analyzed the occurrence of myocarditis after the first and second doses.
They found that of 304 people with symptoms of myocarditis, 21 had already received a diagnosis of it. Of the remaining 283 cases, 142 occurred after receiving the vaccine; of these, 136 diagnoses were definitive or probable. The clinical presentation was considered mild in 129 recipients (95%); one case was fatal.
In his own words: “The incidence of myocarditis, although low, increased after receiving the vaccine, particularly after the second dose among young male recipients. The clinical presentation of myocarditis after vaccination was generally mild ”.
The other research is titled “Myocarditis after COVID-19 Vaccination in a Large Healthcare Organization.”
In this case, the scientists searched the database of Clalit Health Services, Israel’s largest healthcare organization, for diagnoses of myocarditis in patients who had received at least one dose of the Pfizer – BioNTech vaccine. . They then analyzed the incidence of myocarditis up to 42 days after the first dose of the biologic.
Among more than 2.5 million vaccinated members of the organization aged 16 and over, 54 cases met the criteria for myocarditis.
The estimated incidence per 100,000 people who had received at least one dose of the vaccine was 2.13 cases, which equates to 95 percent confidence in the biological.
The highest incidence of myocarditis (10.69 cases per 100,000 people) was reported in male patients between 16 and 29 years of age.
76 percent of myocarditis cases were described as mild and 22 percent as intermediate; one case was associated with cardiogenic shock.