Britain’s two-metre social distancing rule is based on no evidence, leading scientists have claimed amid mounting calls to drop the measure.
Two University of Oxford experts argue there is little proof to support the restriction, after reviewing a World Health Organisation paper on the contentious topic.
Of 38 studies, only one looked specifically at coronavirus infections in relation to a specific distancing measure of two metres — and it found it had no effect.
The pair of scientists claimed the evidence in favour of the two-metre rule is of ‘poor quality’ and impacting Britain’s chance to go about normal daily life.
A senior statistician at the University of Dundee also found the data for two-metre guidelines — which informed experts at the WHO — is flawed.
It comes as Tory MPs and the hospitality sector have begged Boris Johnson to make an urgent decision on whether to ease the social distancing rule.
The Prime Minister confirmed at the weekend that he had ordered a ‘comprehensive’ review of the measure, in light of dwindling infection rates.
Results are not due until at least July 4 — the date when pubs, restaurants and salons are expected to open, giving businesses no time to prepare for changes.
Other scientists say ministers are balancing public health with the economy, and the infection rate across the UK is still too high to relax the rule.
Professors at the University of Oxford said there is little evidence to support the restriction after reviewing 172 studies on the topic. Pictured, a poster warning to stay two metres away on the London Underground
The pair of scientists said the evidence in favour of the two-metre rule is of ‘poor quality’ and is impacting our ability to go about daily life. Pictured: A social distancing sign is seen on the first day of reopening for places of worship, June 15
What is the science behind two-metre social distancing rule?
The World Health Organization (WHO) recommends a one metre distance between two people from separate households.
The reason for this, as stated on its website, is that: ‘When someone coughs, sneezes, or speaks they spray small liquid droplets from their nose or mouth which may contain virus. If you are too close, you can breathe in the droplets, including the COVID-19 virus if the person has the disease.’
But other countries have taken advice from their own health experts and social distancing varies from two metres (in the UK) down to one metre (in France)
The two metre rule can be traced back to research in the 1930s that showed droplets of liquid from coughs or sneezes would land within a one-two metre range.
Social distancing varies between different countries:
TWO METRES: UK, Switzerland, US, Spain, Italy
1.5 METRES: Germany, Poland, Netherlands
ONE METRE: Austria, Norway, Sweden, Finland
SO, WHAT HAVE THE STUDIES SHOWN?
Number 10’s chief scientific adviser – Sir Patrick Vallance – has said that the one metre rule is up to 30 times more risky than the two metre rule.
He told MPs earlier this month the risk of spending a minute next to a Covid-19 patient for two minutes was ‘about the same’ as being within a metre of a Covid-19 case for six seconds.
The latest evidence, published in The Lancet, found there was roughly a 2.6 per cent chance of catching the virus when one metre from a Covid patient. But doubling the gap cut the risk to only 1.3 per cent.
However, other scientists have called the data used in the study into question.
Oxford professors Carl Heneghan and Tom Jefferson said the data was ‘poor quality’, while Dr Mike Lonergan at The University of Dundee said: ‘These data give no indication that two metres is better than one metre.’
One of the top scientific advisers to the British Government said the two metre social distancing rule is based on ‘very fragile’ evidence.
Professor Robert Dingwall, a member of Nervtag, referred to it as a ‘rule of thumb’ rather than a scientifically proven measure.
Other experts have said the distance may be a non-scientific estimate that just caught on in countries around the world.
IS TWO METRES ENOUGH?
The UK’s coronavirus social distancing limit is four times too short and the gap should be 26 feet, said experts at the Massachusetts Institute of Technology in March.
They found viral droplets expelled in coughs and sneezes can travel in a moist, warm atmosphere at speeds of between 33 and 100ft per second.
This creates a cloud in the atmosphere that can span approximately 23ft to 27ft (seven metres to eight metres) to neighbouring people, the team said.
Another study by scientists in Cyprus, published a fortnight ago, added to the evidence when it found the two-metre rule may not be far enough.
Researchers found even in winds of two miles per hour (mph) – the speed needed for smoke to drift – saliva can travel 18 feet in just five seconds.
And scientists from the universities of California Santa Barbara and Stanford last week said the two metre rule may have to be trebled when winter strikes.
They found droplets that carry SARS-CoV-2 – the coronavirus that causes Covid-19 – can travel up to 20feet (six metres) in cold and humid areas.
Writing for The Telegraph, Oxford professors Carl Heneghan and Tom Jefferson said: ‘Social-distancing has become the norm.
‘The two-metre rule, however, is also seriously impacting schools, pubs, restaurants and our ability to go about our daily lives.
‘Handwashing and encouragement are what we need, not formalised rules.
‘This means trying to keep a distance from each other where possible and avoiding spending time indoors in crowded places. Much of the evidence informing policy in this outbreak is poor quality.’
The pair, who work at Oxford University’s Centre for Evidence-Based Medicine, combed through an influential review of research published in the medical journal The Lancet on June 1.
It was conducted to inform World Health Organization (WHO) guidance and reviewed data from 172 existing studies on the spread of Covid-19, SARS and MERS.
All 38 studies focused on the effect of social distancing supported one metre — which what the WHO says is substantial enough to avoid infection — or more.
The researchers said keeping one metre apart can slash the risk of catching coronavirus by 80 per cent.
There was roughly a 1.3 per cent chance of contracting the virus when two metres from an infected patient. But halving this gap raised the risk to only 2.6 per cent.
Now, Professor Heneghan and Jefferson have said the studies are unreliable because they use data which suffer recall bias, which is when there is a possibility participants studied can’t remember events accurately.
In this case, it’s not possible to rely on someone’s memory for how closely they stood to other people, and therefore what measure of distance is safe to avoid infection.
An independent review of 15 studies also showed some inconsistencies in the data, numerical mistakes and unsound methods in 13 of them.
The most concerning, the professors said, was only five studies reported specifically on Covid-19 exposure, with only 477 participants and 26 cases of infection.
In only one study was a specific distance measure reported — ‘came within six feet of the index patient’ — and it didn’t show an effect on contracting Covid-19. This means the distance didn’t make any impact on whether people got the virus or not.
A senior statistician and epidemiologist at The University of Dundee has also cast doubts on the research after reviewing the data.
Dr Mike Lonergan found avoiding contact with others is very important, and that staying one metre away may offer slightly more protection but the difference is unlikely to be much.
He said their conclusion – which essentially said two metres was better than one – was ‘based on misunderstandings of the datasets’.
‘These data give no indication that two metres is better than one metre,’ he said.
Former Cabinet ministers Iain Duncan Smith and Greg Clark were among the senior figures calling for an overhaul to the social distancing guidelines in the Commons yesterday.
They pointed out that other countries were using lower limits – including Germany and the Netherlands following 1.5 metres, and Austria and Sweden following one metre.
Chancellor Rishi Sunak hailed the ‘positive impact’ it would have on business and jobs.
Businesses are waiting on tenterhooks for the findings of a ‘comprehensive review’ of the two-metre rule by Downing Street – confirmed by Mr Johnson at the weekend.
If reduced, it means a significant proportion of the hospitality and retail sector could reopen on July 4 – the earliest date for the next phase of lockdown.
For example, figures from the British Beer and Pub Association figures show that, with the current two metre rule, only 20 to 30 per cent of premises will be able to open at a sustainable level.
However, if the rule was reduced to one metre, 70 per cent would be able to open.
The hospitality sector has welcomed the review, warning that it will simply not be viable for them to reopen unless the social distancing rule is cut to no more than one metre.
But Transport Secretary Grant Shapps said the Government would not make any decision until July 4 at the earliest, after No10 yesterday said the result may take ‘weeks’.
Speaking on BBC Breakfast today, Mr Shapps said: ‘We need to make sure that what we do next doesn’t mean that we end up in a situation where the virus comes back in a very big way again.
‘We’ve just had this big unlock of non-essential shops yesterday, we know the next big date is not before July 4.
Two professors at Oxford University’s Centre for Evidence-Based Medicine said research published in the medical journal The Lancet on June 1 was based on ‘poor quality’ data. It was conducted to inform World Health Organization (WHO) guidance. The researchers said keeping one metre apart can slash the risk of catching coronavirus by 80 per cent. There was roughly a 1.3 per cent chance of contracting the virus when two metres from an infected patient. But halving this gap raised the risk to only 2.6 per cent
A sign on the ground reminds people of the 2-metre social distancing guidelines in Belfast, on June 15 as some non-essential retailers reopen from their coronavirus shutdown
A sign reminds customers of the 2-metre social distancing guidelines at Utopia women’s wear store in York, northern England on June 15
London Zoo opened yesterday with two-metre markings on the floor ahead of a new decision on whether the rule is needed
‘At that time we will be expected to take a judgement call on things like the social distancing rules.’
MINISTERS WILL DECIDE ON TWO-METRE RULE. BUT COULD IT COST THEM THE CHIEF SCIENTISTS?
Senior ministers fear the top scientists advising the Government could quit over plans to ease the two-metre rule.
Professor Chris Whitty, the popular Chief Medical Officer, and Chief Scientific Adviser Sir Patrick Vallance have made it clear they believe the current guidance on safe distancing should stay.
But Boris Johnson will tomorrow pave the way for it to be relaxed amid fears it could spark millions of job losses, with hospitality particularly badly hit.
And Chancellor Rishi Sunak said ministers are ‘urgently’ looking at whether it can be relaxed to boost shops and allow more pubs and restaurants to reopen.
He said it would be a decision for ministers rather than scientists as to when the change comes.
The Sunday Times claims Downing Street is concerned at the scale of opposition among scientists, who fear it could lead to a second spike in coronavirus infections.
‘The worry is that Whitty and Vallance could resign,’ a source told the newspaper.
‘It is getting to the stage where they are threatening to minute their opposition to moving from two metres. Those minutes get formally released.’
The insistence of the Government’s Scientific Advisory Group on Emergencies (Sage) on maintaining the two-metre rule has caused an intense political backlash, with Tory MPs and the Treasury joining forces to express concern about the economic damage it is wreaking.
Figures released last week showed the economy suffered a 20 per cent drop in GDP in April, the largest ever monthly collapse.
Chancellor Rishi Sunak told the party’s backbench 1922 Committee last week that three-quarters of pubs could open if the distance was cut to one metre, and cited the fact that 24 countries had introduced the flexibility to reduce it.
Mr Johnson’s new review will take advice from a range of experts, including the Chief Medical Officer Chris Whitty and Chief Scientific Adviser Sir Patrick Vallance – but also behavioural scientists and economists. It will operate in addition to a rolling review of the guidance being carried out by Sage.
Prof Whitty has public spoken of the importance of the two-metre rule. He has said social distancing – as well as hand washing, ‘good cough etiquette’, the use of face coverings – will be in place ‘for as long as this epidemic continues’.
Sir Patrick Vallance, the chief scientific adviser, has said there was ‘relatively little room for manoeuvre’ in easing the lockdown measures.
A source told the Sunday Times that they were worried the scientists would ‘minute’ their opposition to any change, meaning it would be published in records of Sage meetings.
Katie Nicholls, chief executive of trade union UKHospitality, called for the Government to provide urgent clarity for the hospitality sector, a call echoed by Labour’s shadow business minister Lucy Powell.
Ms Nicholls told BBC Breakfast: ‘It employs 2.3million people, so it’s a huge industry that doesn’t have certainty about an opening date, doesn’t know when it can take bookings, doesn’t know what guidelines it will be opening under, and potentially could be opening within three weeks.
‘With all of that uncertainty it makes it a very anxious environment for our teams and our staff members, and we can’t reassure them about their jobs.’
Shadow business minister Lucy Powell said: ‘We urge the government to publish an action plan which maximises economic viability, whilst minimising the risk to the health of customers and staff.
‘If they fail to act, our communities will lose much-loved pubs, bars and restaurants, and we’ll see a wave of closures and unemployment which will damage villages, towns and cities across the country.’
Health minister Ed Argar said yesterday the two metre rule may be relaxed if changes are made to the rules around face coverings – which evidence is beginning to suggest is more protective than any other disease control intervention.
He said the possibility of compulsory face coverings in shops and the like was one of a ‘menu of options’ that was being considered in the review.
The two-metre review announcement comes as the WHO urged the Government not to lift the lockdown until it is proven its widely criticised coronavirus contact-tracing system works.
There are doubts in government over whether the test and trace system is ready to deal with the potential increase in cases.
Mr Johnson said falling numbers of diagnosed coronavirus cases has given the Government ‘more margin for manoeuvre’ in easing the two-metre rule.
But only last week Professor Catherine Noakes, part of the Scientific Advisory Group for Emergencies (Sage), said it was not safe at this time.
She said coronavirus transmission is still too high in Britain to relax the social distancing two-metre rule.
There were around 8,000 people still being infected every day two weeks ago, which has dropped to about 5,500 now, according to the Office for National Statistics.
Dr Michael Tildesley, infectious disease scientist at the University of Warwick, said reducing the social distancing restriction from two metres to one ‘will result in an increase in risk’.
He told the BBC: ‘The evidence is still slightly unclear – depending upon the studies, it could be anything from about twice the risk to 10 times the risk.’
Chancellor Rishi Sunak has said it would be ministers, not scientists, who would make the decisions on any easing.
It is feared this could rub top scientists advising the Government the wrong way, considering their focus is on protecting public health.
But the PM’s spokesman said the review ‘will draw on advice from scientific and medical experts as well as economists and papers from Sage’.