Heart conditions, myocarditis and pericarditis, must be listed as possible side effects of the two mRNA vaccines, the safety committee of the European Medicines Agency (EMA) said today.

Such cases primarily occurred within 14 days from vaccination, more often after the second dose and in younger adult men, the EMA said. This is in line with findings from US health officials last month.

The EMA panel also recommended that people who have a history of capillary leak syndrome (CLS) must not be vaccinated with J&J’s single-shot vaccine. The watchdog in June asked CLS to be added as a side effect from AstraZeneca’s shot.

Both AstraZeneca and J&J vaccines use different versions of a cold virus to deliver instructions for making coronavirus proteins to produce an immune response.