There is a "likely" link between cases of inflammation in the heart and injection of messenger RNA Covid vaccines but the benefits of these sera outweigh the risks, the WHO said on Friday, confirming American expertise.
In a statement, experts from the World Health Organization's (WHO) Global Advisory Committee on Vaccine Safety explain that cases of myocarditis - an inflammation of the heart muscle - and pericarditis - an inflammation of the membrane surrounding the heart - have been reported in several countries, particularly in the United States.
More common cases in young men
"The reported cases generally occurred in the days following vaccination, more frequently in young men and more often after the second dose of the messenger RNA vaccines against Covid-19", they indicated.
After reviewing the information available to date, WHO experts conclude that “current data suggests a probable causal link between myocarditis and messenger RNA vaccines”.
However, they point out, "the benefits of messenger RNA vaccines outweigh the risks in reducing hospitalizations and deaths from Covid-19 infections."
Evaluate the long-term effects
WHO experts also indicate that the available data suggest that the immediate course of myocarditis and pericarditis after vaccination is generally mild and responds to treatment.
"A follow-up is underway to determine the effects on the long term", they specify.
WHO experts will continue to assess the situation in order to update their recommendations.
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According to the WHO, the Pharmacovigilance Risk Assessment Committee of the European Medicines Agency (EMA) examined, at its meeting from July 5 to 8, the latest data from Europe and confirmed the existence of a plausible causal relationship between myocarditis and messenger RNA vaccines.
Myocarditis is a rare disease, which experts believe is usually triggered by a virus. The most common symptom is chest pain, and it is often treated with anti-inflammatory drugs, or if needed, by providing oxygen support. The first cases of myocarditis were reported in Israel, where the immunization campaign was faster than in most countries.