Boris Johnson‘s hope to deliver normality in time for Christmas is an “enthusiastic approach that is premature” because the community infection rate is too high, a public health professor has said.
Linda Bauld, professor of public health at the University of Edinburgh, said social distancing could only be removed if there were no coronavirus cases across the UK.
And England’s chief medical officer, Professor Chris Whitty, said social-distancing measures will need to stay in place until a vaccine or highly-effective treatment is discovered.
Meanwhile the Department of Health said it was pausing daily death statistics while it investigated statistical flaws which could have inflated the figure.
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Boris Johnson may struggle to deliver 'significant return to normality' by Christmas, leading scientists warn
Boris Johnson may struggle to deliver his vision of a "significant return to normality" in time for Christmas, leading scientists have warned.
The prime minister signalled another significant easing of coroanavirus lockdown restrictions in England on Friday, relaxing work-from-home guidance and paving the way for theatres and sports stadiums to reopen.
At a No 10 press conference, he said it was his "strong and sincere hope" that ministers would be able to review the remaining restrictions from November onwards "possibly in time for Christmas".
However, Sir Mark Walport, a former chief scientific adviser, said it could prove difficult to achieve with respiratory illnesses tending to flourish in the colder weather.
He said while the disease was declining, there were still between 3,000 and 11,000 new cases a day in England.
"It is going to be difficult. We know that winter is when respiratory viruses thrive so it is going to be tough," he told BBC2's Newsnight.
"The prime minister said 'Hope for the best, plan for the worst'. Of course what we need to do as far as possible is prevent the worst."
His comments echoed the chief medical officer for England Professor Chris Whitty who warned measures such as hand-washing, isolation and household quarantine would be needed for a "prolonged period".
Giving evidence to the Lords Science and Technology Committee on Friday, he said: "It has not gone away. So, all of those need to continue for a long period of time."
The government's chief scientific adviser Sir Patrick Vallance - who had previously warned against easing the work-from-home guidance - told the committee the winter would be a "very complex time" with people going down with other illnesses which were not Covid-19.
England could return to normality by Christmas, transport secretary says
Grant Shapps said it is possible for the country to return to normality by Christmas.
The transport secretary told BBC Breakfast the prime minister's announcement was about giving people a "sense of direction".
He added: "It's giving people a road map, really, so we can give people some hope whilst planning for the worst as well.
"We want to give people some sense of direction, because a lot of people are running businesses or rely on the Christmas period and need to know that if everything goes well that this is our intention.
"But you can't get away from the fact that the virus is still, in many ways, a bit of an unknown, and of course it depends how millions of people respond and how good and alert we are in terms of all the things we know, like washing your hands and for the time being keeping that distance of one metre plus."
Mr Shapps said there is capacity on public transport for more people to use it to go back to work.
He added: "We are quite close to full capacity but the usage of public transport is way down.
"We have been very careful to ask people not to flood back too quickly and they have not, and so we are seeing many cases of quite empty, for example, trains.
"There's more capacity there, you can now return. Anyone, not just key workers, can use public transport.
"I would recommend trying to avoid the busier times of day, but as people return to work - and the prime minister asked employers and employees to look at doing that particularly from August 1 - the public transport is there."
Mr Shapps said social distancing rules are still in force on public transport.
"There's a lot of space on our public transport right now, it's probably being used less than 20%, and there's capacity even with social distancing which is now, of course, one metre plus with mitigating factors like face coverings.
"We don't have, right now, an issue with capacity on our railway and we can take a lot more people than we are at the moment."
Return to pre-lockdown normality 'a long way off', Sage scientist says
Professor John Edmunds, a member of the government's Scientific Advisory Group for Emergencies (Sage), has said a return to pre-lockdown normality is "a long way off".
"Unfortunately I think it is quite a long way away," he told the BBC Radio 4 Today programme.
"If what you mean by normality is what we used to do until February and the middle of March this year - go to work normally, travel on the buses and trains, go on holiday without restrictions, meet friends, shake hands, hug each other and so on - that's a long way off, unfortunately.
"We won't be able to do that until we are immune to the virus, which means until we have a vaccine that is proven safe and effective.
"If we return to those sort of normal behaviours the virus will come back very fast."
Social distancing may be necessary for some time, England's chief medical officer says
Social distancing may be necessary for a long time, England's top medic has said, warning that eliminating coronavirus is highly unlikely.
Professor Chris Whitty told the Lords Science and Technology Committee that, while certain hygiene measures will be around for the foreseeable future, keeping a safe distance from others will also need to be maintained.
He further told the peers on Friday that aiming to eliminate Covid-19 from the UK was "quite optimistic".
Prof Whitty said: "There are some things which we started right at the beginning, which absolutely have to continue for a prolonged period of time, washing hands, isolation, household isolation.
"And then we've added to that things like contact tracing, most recently face coverings.
"And these are issues of, and issues around distancing, which have been varied but the reality is distancing remains an important part of this mix and how it's interpreted in different governments has evolved.
"But it has not gone away. So, all of those need to continue for a long period of time."

Government health advisers pour cold water on Boris Johnson’s social distancing hopes
The government’s most senior health advisers appeared to cast doubt on Boris Johnson’s suggestion the UK could see a significant return to normality in time for Christmas, just hours after the prime minister made the prediction, political editor Kate Devlin reports.
Mr Johnson said that if progress in the fight against Covid-19 continued it might be possible to move away from social distancing measures, including the one metre-plus rule currently in force, by November.
He added: “It is my strong and sincere hope that we will be able to review the outstanding restrictions and allow a more significant return to normality from November at the earliest – possibly in time for Christmas”.
Patrick Vallance, the chief scientific adviser, and Chris Whitty, the chief medical officer, were not at Mr Johnson’s side at a press conference in Downing Street in which he announced a cautious lifting of the government’s ‘work from home’ message.
Later both appeared to suggest a less optimistic outlook for the UK.
US coronavirus cases rise by over 70,000 for second day in a row
For a second day in a row, US coronavirus cases rose by over 70,000.
Cases on Friday rose by at least 70,674 after climbing by a record 77,499 on Thursday, the largest increase posted by any country since the pandemic started, according to a Reuters tally.
US deaths on Friday rose by at least 912, the fourth day in a row that fatalities have risen by over 900 a day.
Coronavirus cases are rising in 41 of 50 states, according to a Reuters analysis of cases the past two weeks compared with the previous two weeks. Deaths are rising in 19 states.

English councils get powers to order local lockdowns
English councils have been granted new powers to impose local lockdown measures.
Local authorities will be able to shut down shops and cancel events in their area to control any coronavirus outbreaks, Zoe Tidman reports.
Boris Johnson said councils in England would have the enhanced powers from Saturday, after he set out new details for "a significant return to normality" by Christmas.
The prime minister said: “They will be able to close specific premises, shut public outdoor spaces and cancel events.
“These powers will enable local authorities to act more quickly in response to outbreaks where speed is paramount.”
Record increase in global coronavirus cases recorded
The World Health Organisation reported a record increase in global coronavirus cases on Friday, with the total rising by 237,743 in 24 hours.
The biggest increases were from the United States, Brazil, India and South Africa, according to a daily report.
The previous WHO record for new cases was 230,370 on July 12. Deaths have held steady and averaged less than 5,000 a day in July.
Total global coronavirus cases were approaching 14 million on Friday, according to a Reuters tally, marking another milestone in the spread of the disease that has killed more than 590,000 people in seven months.
Coronavirus vaccine research must not be stolen by spies, head of UN says
The head of the United Nations has condemned any attempt by countries to steal details of coronavirus vaccine research from their rivals.
Secretary-general Antonio Guterres said it was "very important" that the intellectual property rights of scientists seeking to develop a vaccine were protected.
At the same time he stressed it was essential that if a successful vaccine was produced, it was made available to "everybody, everywhere" around the world.
His warning came after Britain, the United States and Canada accused hackers linked to Russian intelligence of targeting vaccine researchers- including those in the UK - in an attempt to steal details of their work.
Moscow has strongly denied the allegations.
Mr Guterres told the BBC Radio 4 Today programme: "Any espionage in relation to vaccines is to be condemned as we must condemn any policies that divide the world instead of conceiving the vaccine as a global public good, conceiving the vaccine as a people's vaccine, that must be accessible to everybody, everywhere.
"Just to develop a vaccine for each country's population and forget about the others is also something that is unacceptable.
"It is very important the intellectual property is protected, that nobody spies on anybody, but it is also important that a vaccine must be available to everybody, everywhere and affordable by everybody, everywhere."
Mr Guterres lamented the failure of countries to come together to fight the virus, blaming the "dysfunctional" state of relations between the world's biggest powers such as the US, Russia and China.
He said it was essential that the developed countries did more to support the poorer ones, otherwise they would pay a "terrible price".
"We will not be safe in relation to the pandemic if everybody is not safe," he said.
"So to support the global south and to support global institutions to fight the pandemic is absolutely essential to preserve the interests of the most developed countries of the world.
"If the developed countries try to solve their own problems and forget about the rest in the end they will pay a terrible price."

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Some parts of Leicestershire lockdown to be lifted
Parts of Leicestershire will be freed from additional lockdown restrictions from as soon as this weekend following a review by public health experts, the government has said.
Areas outside of Leicester City and the borough of Oadby and Wigston will align with national lockdown rules in England from Saturday.
It means that from 18 July non-essential shops, bars, restaurants and hairdressers not in the continuing protected zone will be permitted to open.
Schools and childcare settings outside the protected area will also be able to open from the same date, in line with national restrictions.
But businesses and people living in Leicester City and the borough of Oadby and Wigston will have to wait longer to see their additional restrictions lifted, due to a higher prevalence of coronavirus, the government said.
Non-essential shops and schools in these areas will be allowed to open from 24 July, but bars, restaurants and hairdressers will stay closed, with a review due to take place by 1 August.
Thanking the people of Leicester for following public health advice, health secretary Matt Hancock said: "I know the past two weeks have been difficult for those living in and around Leicester, especially those who have been shielding for so many weeks.
"While we are not yet in a position to lift all the restrictions in place, we are now able to take cautious steps to allow areas outside of Leicester City and the borough of Oadby and Wigston to fall in step with national guidelines and introduce some relaxations within the City of Leicester and the borough of Oadby and Wigston.
"I realise that this will be frustrating for those areas that remain under additional restrictions and I am determined to be straight with you all, we will ease restrictions as soon as the data shows that it is safe to do so."
Australia delays opening of parliament due to coronavirus spread
Australia's prime minister has delayed the opening of parliament for several weeks due to the continued spread of coronavirus through the country's two most populous states.
Scott Morrison asked the speaker of the parliament to cancel a two-week session due to start on 4 August, out of concern about the Covid-19 pandemic.
The request was seen as a formality as the speaker is a member of Mr Morrison's Liberal Party and the opposition Labor Party accepted the call.
Lawmakers are to meet at the next planned session on 24 August.
"The government cannot ignore the risk to parliamentarians, their staff, the staff within the parliament and the broader community," Mr Morrison said in a written statement, adding he acted based on the advice of medical authorities.
Iran has as many as 25 million cases, president estimates
Iran's president estimated as many as 25 million Iranians could have been infected with the coronavirus since the outbreak's beginning, as he urged the public to take the pandemic seriously, the state-run IRNA news agency reported Saturday.
Hassan Rouhani cited a new Iranian Health Ministry study in offering the unprecedentedly high numbers.
Mr Rouhani also said about 30 to 35 million will be infected to the virus in the coming months.
"We have to estimate that 30 to 35 million people will be exposed to the virus, which is very important", Mr Rouhani added.
Iranians officials have not explained on what the report's estimates are based. The study has so far not been made publicly available.
Referring to the report, Mr Rouhani said it also predicts that the number of hospitalizations will soon be "twice as many as we have seen in the last 150 days."
Iran has seen the worst outbreak in the Middle East, with more than 270,000 confirmed cases and at least 13,979 deaths. That includes 2,166 new cases and 188 deaths in the last 24 hours, according to the Health Ministry.
UK pauses daily death toll updates
The UK has paused its daily coronavirus death toll updates after the government ordered a review into the calculation of the data over concerns the toll might have been exaggerated.
Academics have said the way Public Health England (PHE) calculates the figures in England means they may be distorted compared to other parts of the UK.
"Currently the daily deaths measure counts all people who have tested positive for coronavirus and since died, with no cut-off between time of testing and date of death," a message on the government's website said.
"There have been claims that the lack of cut-off may distort the current daily deaths number. We are therefore pausing the publication of the daily figure while this is resolved."
On Friday, Matt Hancock, the health secretary, ordered a review into PHE's reporting after the academics said patients who tested positive for coronavirus, but were successfully treated, would still be counted as dying from the virus "even if they had a heart attack or were run over by a bus three months later".
Local lockdown may not have been as effective in BAME communities, scientists say
Lockdown measures imposed in late March to slow down the spread of coronavirus may not have been as effective in black, Asian and minority ethnic (BAME) communities because of the "one-size-fits-all approach", scientists have said.
Academics at the University of Leicester found that Covid-19 cases continued to rise in BAME groups in certain parts of Leicester in the three weeks after the announcement was made, while rates in white groups "dropped off very sharply".
They said the findings, published recently in the journal EClinicalMedicine by The Lancet, raise "serious questions" on whether lockdown on its own is effective for a diverse population.
Dr Manish Pareek, an associate clinical professor in infectious diseases at the University of Leicester, told the PA news agency: "Obviously, lockdown has had a huge impact in reducing infection rates but the question is, is it enough for certain parts of the country?
"Lockdown as a whole is quite a blunt tool... perhaps what we should be thinking about is a more nuanced approach which allows people to work with local solutions."
Grant Shapps becomes first senior politician to declare he is taking a summer holiday abroad this year
Grant Shapps has become the first senior politician to break ranks and declare he is taking a summer holiday abroad this year.
The transport secretary said he and his wife Belinda had decided to take advantage of the relaxation of Foreign Office guidance on non-essential overseas travel.
"My wife looked at all of these new changes that were made and has now booked a break for the first time for a couple of years," he told the BBC Radio 4 Today programme.
South Africa poised to join top five worst-affected countries
South Africa is poised to join the top five countries most affected by coronavirus, while breathtaking numbers around the world were a reminder a return to normal life is still far from in sight.
Confirmed cases worldwide have topped 14 million and deaths have surpassed 600,000, according to Johns Hopkins University data, a day after the World Health Organisation reported a single-day record of new infections at more than 237,000.
Death tolls in the United States are reaching new highs, and India's infections are over one million.
Iran's president made the startling announcement that as many as 25 million Iranians could have been infected, the state-run IRNA news agency reported Saturday.
Hassan Rouhani cited a new Health Ministry study that has not been made publicly available. Iran has seen the worst outbreak in the Middle East with more than 270,000 confirmed cases.
Experts believe the true numbers around the world are higher because of testing shortages. And as countries try to ease lockdowns, new ripples of cases follow.
South Africa on Saturday could join the US, Brazil, India and Russia as the most badly hit countries, as its cases near 350,000. Current case trends show it will surpass Peru.
It comes as the world marks Mandela Day, remembering South Africa's first black president and his legacy of fighting inequality.
More than 140 offenders released from prison and housed in hotels during lockdown
More than 140 offenders were housed in hotels and bed and breakfasts after they were released from prison during lockdown.
The Ministry of Justice (MoJ) said the move was "a last resort" to prevent offenders from becoming homeless and to reduce the risk of spreading coronavirus.
Of the 304 offenders who were due for release and provided with accommodation, 136 were housed in hotels or B&Bs after all other options were exhausted, the MoJ said.
Additionally, of the 172 offenders released under the End of Custody Temporary Release scheme - in which prisoners who are within two months of their release date are temporarily released from custody - six were housed in hotels.