The Pfizer/BioNTech and Moderna jabs have been linked to cases of mild heart inflammation – but the benefits still outweigh the risks, according to European and UK health agencies.
Myocarditis – inflammation of the heart muscle – and pericarditis – inflammation of the lining around the heart – have been observed in a small number of people who had the vaccines.
Both the European Medicines Agency (EMA) and the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) say that younger men were most likely to see the complication, especially after their second jab.
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The EMA and MHRA are recommending that healthcare professionals and the public be on the lookout for symptoms of heart inflammation in people who have had the two vaccines.
This includes chest pain, shortness of breath, palpitations and an irregular heartbeat.
Anyone with these symptoms who has been vaccinated should seek “immediate medical attention”, the MHRA said.
But most cases were “mild” and people who reported the symptoms tended to recover with normal treatment and rest.
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The Pfizer and Moderna jabs are mRNA vaccines, which work by training your body to recognise and destroy a particular part of the coronavirus called the spike protein, should you get infected with the real thing.
The MHRA says it has received 102 reports of inflammation following doses of the Pfizer jab, and seven cases following administration of the Moderna jab.
Roughly 18 million first and 11 million second doses of the Pfizer vaccine have been given out in the UK, while around 880,000 Moderna first doses have been given.
The EMA says, after 177 million total Pfizer doses were given out, 283 inflammation cases were reported.
And after 20 million Moderna doses, 38 inflammation cases were reported.
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While five of the European cases saw someone die, the EMA says these were all in older people or those with other conditions.
The cases were most commonly found in men under 40 and within 10 days of a second dose.
The majority of those recovered quickly with the normal treatments for myocarditis and pericarditis as well as rest.
The EMA is also making updates to list myocarditis and pericarditis as side effects of the jabs.
The MHRA said: “The COVID-19 vaccines remain highly effective in protecting people from COVID-19 and have already saved thousands of lives.
“These events are extremely rare and tend to be mild when they do occur.
“Our advice remains that the benefits of getting vaccinated outweigh the risks in the majority of people.
“It is still vitally important that people come forward for their first and second vaccination when invited to do so, unless advised otherwise.”
No causal link has been found between the AstraZeneca or Johnson & Johnson shots and heart inflammation.