Food and Drug Administration (FDA), a US drug regulator, has warned that Pfizer Inc (PFE.N)/BioNTech (22UAy.DE) and Moderna (MRNA.O) COVID vaccines could trigger rare heart inflammation in some recipients after the second jab.

FDA directed the drug manufacturers on Friday, June 25, to update their literature to include the rare myocarditis and pericarditis which have been noted but not on widespread scale.

The regulator tweeted: ‘‘As part of our commitment to vigilant safety monitoring of COVID19 vaccines, FDA updated the public on its on-going evaluation of adverse event reports of myocarditis and pericarditis following vaccination with Moderna and Pfizer-BioNTech COVID-19 vaccines.’’

Attached in the FDA tweet was a reassurance by the FDA Acting Commissioner Janet Woodcock that ‘although myocarditis and pericarditis incidents are rare, and could present some minute degree of risks; the benefits of the inoculation generally outweigh the risks.’

She proceeded by saying that the jabs are a sure bet against patients’ chances of developing severe illnesses.

Reuters reported on Friday that as of June 11, the U.S. Vaccine Adverse Event Reporting System (VAERS) had registered 1,200 cases of the health problem out of the 300 million doses administered so far.

According to Reuters, US Centre for Disease Control and Prevention (CDC) had noted 309 hospitalisations from the rare condition, out of which 295 were successfully treated and patients discharged.

The problem has been reported to be rampant in younger men below 30. The drug makers are yet to give a statement about the development.

Past cases

It is not the first health condition being detected in the administration of the vaccine. Earlier this year, AstraZeneca had to battle various safety fears after many consuming countries noted concerns over its use.

Some European countries played hardball in endorsing the drug citing health risks in the population under the age of 60.