Twelve children aged between 15 and 17 are among those reported with suspected heart inflammation after having the Comirnaty COVID-19 vaccination, according to the TGA’s latest safety update.

The report comes as vaccination of 12-to-15-year-olds is set to begin on Monday.

The cases — 10 boys and two girls — are among 370 reports of suspected myocarditis and/or pericarditis made to the TGA up to 7 September from an estimated 10.7 million Pfizer vaccinations given so far in the rollout.

Speaking to Australian Doctor, paediatric infectious diseases specialist Professor Robert Booy said that a one in 10,000 risk of myocarditis in adolescents after the Pfizer vaccine was probably a good estimate.