Pierpaolo Sileri, Italy‘s deputy health minister, claimed he had mentioned the plan in a call with the country’s prime minister, Giuseppe Conte, on March 13.
Herd immunity occurs when enough of the population has had a disease that it can no longer spread effectively.
For it to develop against Covid-19, scientists say around two thirds of people would have to had the virus – a process that would kill tens of thousands of Britons.
The controversial herd immunity plan was briefly touted as an option by Number 10’s chief scientific adviser Sir Patrick Vallance in March.
It was later abandoned because of public outrage. Downing Street has since denied that it ever planned to seriously pursue the plan.
Another scientist, Professor Graham Medley, said he and SAGE colleagues were ‘dismayed’ in the epidemic’s early stages that politicians weren’t taking the virus seriously.
Mr Sileri’s and Professor Medley’s revelations come in a Channel 4 Dispatches documentary which airs tomorrow, Wednesday, at 9pm.
In response to the documentary the Government insists ‘we have taken the right steps at the right time’ and said the public should avoid ‘accepting the claims of a rushed documentary’.
Boris Johnson allegedly told the Italian Prime Minister, Giuseppe Conte, that he was considering a policy of developing herd immunity to the coronavirus at a time when Italy was in lockdown, the country’s deputy health minister said
Pierpaolo Sileri, a qualified surgeon and Italy’s deputy health minister since last year, was diagnosed with the coronavirus himself in mid-March.
He recalled speaking to the country’s prime minister, Mr Conte, who had had a phone call with Boris Johnson on March 13.
Mr Sileri told Dispatches: ‘I spoke with Conte to tell President Conte that I’d tested positive.
‘And he told me that he’d spoken with Boris Johnson and that they’d also talked about the situation in Italy.
‘I remember he said: “He told me that he wants herd immunity”.
‘I remember that after hanging up, I said to myself that I hope Boris Johnson goes for a lockdown.’
For herd immunity to develop, a majority of a population must have a disease, recover from it and build up a tolerance to stop them getting it again.
Scientists believe that for this to work for Covid-19, around 60 per cent of people would have to have the virus – about 40million people in the UK.
Currently, the coronavirus appears to have a death rate of around one per cent, suggesting that 400,000 people could have died in the process.
And scientists still do not know if people actually develop long-lasting immunity against the coronavirus, or whether they are able to catch it more than once.
Pierpaolo Sileri, a qualified surgeon and Italy’s deputy health minister (left) and Professor Graham Medley, a member of the Scientific Advisory Group for Emergencies (SAGE), have come out in criticism of the British Government’s handling of the coronavirus crisis
Sir Patrick Vallance, chief scientific adviser to the UK Government, spoke about herd immunity in March as if officials were genuinely considering it as an option.
When asked about lockdown on March 13 – Italy was already in lockdown by that point – Sir Patrick said that it was ‘impossible’ for a country to attempt to self-isolate its entire population.
WHAT IS HERD IMMUNITY?
Herd immunity is a situation in which a population of people is protected from a disease because so many of them are unaffected by it – because they’ve already had it or have been vaccinated – that it cannot spread.
To cause an outbreak a disease-causing bacteria or virus must have a continuous supply of potential victims who are not immune to it.
Immunity is when your body knows exactly how to fight off a certain type of infection because it has encountered it before, either by having the illness in the past or through a vaccine.
When a virus or bacteria enters the body the immune system creates substances called antibodies, which are designed to destroy one specific type of bug.
When these have been created once, some of them remain in the body and the body also remembers how to make them again. This provides long-term protection, or immunity, against an illness.
If nobody is immune to an illness – as was the case at the beginning of the coronavirus outbreak – it can spread like wildfire.
However, if, for example, half of people have developed immunity – from a past infection or a vaccine – there are only half as many people the illness can spread to.
As more and more people become immune the bug finds it harder and harder to spread until its pool of victims becomes so small it can no longer spread at all.
The threshold for herd immunity is different for various illnesses, depending on how contagious they are – for measles, around 95 per cent of people must be vaccinated to it spreading.
For polio, which is less contagious, the threshold is about 80-85 per cent, according to the Oxford Vaccine Group.
He said: ‘We want to suppress it [the virus], not get rid of it completely, which you can’t do anyway, and also allow enough of us who are going to get mild illness to become immune to this to help with the sort of whole population response which would protect everybody.’
Sir Patrick added: ‘We think that this virus is likely to be one that comes back year on year, become like a seasonal virus, and communities will become immune to it, and that’s going to be an important part of controlling this longer term.’
However, public backlash against the plan which would see millions infected and tens or even hundreds of thousands of people die, took herd immunity of the table.
It stopped being mentioned in discussions and 10 Downing Street has denied considering it as a plan ever since.
But top scientists say they had to battle hard to get officials to take the virus seriously in the outbreak’s early days.
Professor Graham Medley, an infectious disease expert at the London School of Hygiene & Tropical Medicine and member of the Scientific Advisory Group for Emergencies (SAGE), told Channel 4: ‘We already knew that this virus was going to cause an awful lot of death and disability and would require an awful lot of NHS resource…
‘So it was with some dismay that we were watching senior politicians behaving in a way that suggested that this was not something that was too serious.’
Professor Medley said the Government was told in late February that half a million Brits could die if there was no lockdown, but the country didn’t go into lockdown until March 23.
‘We had been saying it on SAGE… from the end of February,’ he said.
‘It was a public perception that something changed on the 16th March, but nothing changed within SPI-M [a SAGE sub-group] or within SAGE other than a palpable relief that this was being seen as a very serious event.’
In response to Mr Sileri’s claim that Boris Johnson said he planned to pursue herd immunity, a UK Government spokesperson said: ‘This is an unprecedented global pandemic and we have taken the right steps at the right time to combat it.
‘The Government has been very clear that herd immunity has never been our policy or goal.
‘At every stage, the Government has been guided by the advice of experts from Sage and its sub-committees – advice which has now been published on gov.uk.
‘Our response has ensured that the NHS has capacity for everyone who needs it and that it can provide the best possible care for people who become ill.
‘Instead of accepting the claims of a rushed documentary which set out to find failings rather than to inform, we advise viewers to read the published evidence themselves.’
Britain’s Coronavirus Catastrophe: Did the Government Get it Wrong? will air on Channel 4 at 9pm on Wednesday, June 3