MRNA Vaccine Benefits Outweigh Heart Risks, CDC Reports

(Bloomberg) -- The benefits of messenger RNA Covid-19 vaccines clearly outweigh the risks despite heart complications seen in a relatively small number of mostly young men, according to the U.S. Centers for Disease Control and Prevention.

Roughly 1,200 cases of myocarditis, or inflammation of the heart wall, were reported in people who received mRNA vaccines, the CDC said in its Morbidity and Mortality Weekly Report on Tuesday. But with about 296 million doses of mRNA vaccines having been administered as of June 11, the benefit is clear in all populations, including adolescents and young adults, the researchers reported.

Vaccines made by Moderna Inc. and the Pfizer Inc.-BioNTech SE partnership are the only mRNA inoculations authorized for emergency use in the U.S. The issue was first explored in a June 23 meeting of the CDC's Advisory Committee on Immunization Practices.

There has been increasing concern that these possible cardiovascular side effects could threaten vaccine uptake among young Americans as the highly transmissible delta variant is hitting under-vaccinated hot spots of the country.

The agency report said that fact sheets should be provided before mRNA vaccinations. The U.S. Food and Drug Administration Emergency Use Authorization has been modified to include information on myocarditis after receipt of mRNA Covid-19 vaccines.

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