Giving emotional evidence to the Covid-19 Inquiry, Prof Fong described the pandemic as the ‘biggest national emergency that this country has faced since World War II'.
The former national clinical adviser said the scale of death experienced by intensive care teams was ‘truly astounding'.
He related how an intensive care doctor had told him: ‘It's been like a terrorist attack every day since this started and we don't know when the attacks are going to stop.'
He described scenes where staff had run out of body bags and were issued with ‘nine-foot clear plastic sacks and cable ties'.
Prof Fong said staff were ‘traumatised' and suffered recurring nightmares ‘about feeling like they were just throwing bodies away'.
The former clinical adviser said he had been at the scene of the Soho bombings in 1999 and had attended a number of major incidents but nothing had been as bad as Covid.
He described one unit as being like a ‘scene of hell' with staff forced to wear diapers because they did not have the time to go to the toilet.
Speaking later Professor Chris Whitty said the UK had a lower ICU bed capacity than peer countries which meant there was less reserve in terms of an emergency, which had been a ‘political choice'.