Marcus de Brun repeated a claim made in a controversial tweet in July 2021 that injecting a child with a genetic-based vaccine was “a crime against humanity”

An expert witness told a fitness-to-practise hearing of the Medical Council that Marcus de Brun, who operated his own medical practice in Rush, Co Dublin, had disagreed with all sorts of public health guidelines and initiatives in a large number of posts on his Twitter account.

A memo on the terms of reference for the inquiry is expected in the coming weeks.