Health bosses have warned of “extremely rare” side effects causing heart inflammation in people who have received a Pfizer/BioNTech or Moderna Covid-19 vaccine.
The Medicines And Healthcare Products Regulatory Agency (MHRA) said medics and people who have received the jab should learn the signs of myocarditis and pericarditis.
Both relate to inflammation of different parts of the heart, and can cause chest pain, shortness of breath and palpitations.
But with 109 reports out of almost 30 million jabs, and generally only mild illness from it, medical chiefs say the benefits of getting vaccinated still “outweigh the risks”.
Who does it affect?
This week the MHRA and Commission On Human Medicines (CHM), a panel of independent expert advisors to the UK government, updated the guidance around the two vaccines.
They said cases occurred “most frequently” in men under 40, and within 10 days of their second dose.
A vaccine update said: “Most of these cases were mild and individuals typically recovered within a short time and with symptomatic treatment and rest.”
But the organisations warned that anyone who has been vaccinated and experiences any symptoms of myocarditis and pericarditis should seek “immediate” medical attention.
They said similar cases have been reported after the Oxford/AstraZeneca vaccine as well, but so far there is “insufficient evidence” to extend the warning.
How rare is this?
The announcement was made after patients reported their illness through the Yellow Card system, used to monitor side effects after the Covid jabs.
Clinical trials all found the vaccines to be safe, with ongoing safety monitoring standard practice for any new medication brought into use in the UK.
The MHRA said, as of June 23, an estimated 18 million first doses and 11 million second doses of the Pfizer/BioNTech vaccine have been administered so far.
Of these, there have been 60 reports of myocarditis and 42 of pericarditis.
Around 880,000 Modern jabs have been given, leading to five myocarditis and two pericarditis reports.
Benefits ‘outweigh the risks’
The MHRA said: “Vaccinated individuals should be advised to seek immediate medical attention should they experience new onset of chest pain, shortness of breath, or symptoms of disturbance of cardiac rhythm.
“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.”