According to a review by the US Centres for Disease Control and Prevention, the risk of cardiac problems was much higher after Covid-19 infection than after mRNA immunisation created by Pfizer or Moderna against the lethal infectious disease (CDC).
What reports say?
The CDC noted in its latest weekly Morbidity and Mortality Weekly Report that these findings, which were for both males and females in all age groups, supported the ongoing use of recommended mRNA Covid-19 vaccinations among all eligible persons aged over 5 years (MMWR).
Cardiac complications, including myocarditis (inflammation of the heart muscle) and pericarditis (swelling and irritation of the thin, saclike tissue surrounding the heart), as well as the multisystem inflammatory syndrome (MIS) (a rare but serious complication of SARS-CoV-2 infection with frequent cardiac involvement and affecting primarily children) have been linked to Covid infection and mRNA vaccination.
Electronic health record?
The researchers computed the occurrences of all these cardiac events among all people using electronic health record (EHR) data from 15,215,178 people aged over 5 years from 40 US health care systems between 1 January 2021 and 31 January 2022.
The prevalence of cardiac events after mRNA Covid-19 vaccination was highest for males aged 12-17 years after the second vaccine dosage. However, after SARS-CoV-2 infection, the risk of cardiac events was 1.8-5.6 times higher than after the second vaccine dose in this demographic group.
For all other categories by sex and age, the risk of cardiac events was also significantly higher – about 2 to 115 times – following SARS-CoV-2 infection than after the first, second, or undetermined dose of mRNA Covid-19 immunisation.
“We found that the incidences of cardiac complications after SARS-CoV-2 infection or mRNA Covid-19 vaccination were low overall, but were higher after infection than after vaccination for both males and females in all age groups,” said corresponding author Jason P. Block of Harvard Medical School in the United States.
The researchers also referenced two studies from Israel and the United Kingdom that found a comparable increase in myocarditis risk following SARS-CoV-2 infection compared to mRNA Covid-19 immunisation.