At Least Four European Countries Limit Use of Moderna Vaccine in People Below 30, Citing Cardiovascular Side Effects

Denmark, Norway, Sweden and now Finland have recommended against the use of the Moderna Covid-19 vaccine for younger people, a move prompted by cardiovascular side effects that though rare, have caused concerns among health authorities in those countries.

Finland's Institute of Health said Thursday it would pause use of the Moderna Covid-19 vaccine among men under the age of 30. Swedish regulators took similar steps Wednesday, according to the Wall Street Journal. Also on Wednesday, Denmark said it would not offer the Moderna vaccine to people under 18 as a precautionary measure.

Similarly to Denmark, Norway announced that people under 18 should not take the Moderna vaccine even if they had already taken the first shot. Norway also recommended that men under 30 take the Pfizer Covid-19 vaccine instead of the Moderna drug, citing U.S. and Canadian data along with research from Nordic countries. The data point to inflammatory heart conditions called myocarditis and pericarditis that occur in very rare cases after Covid-19 vaccination from either Moderna or Pfizer. Leaders are recommending against Moderna in the aforementioned age groups because the rare conditions occur more often with that drug, though both vaccines use the mRNA technology.