Relaxing stay-at-home orders and allowing some non-essential businesses to reopen are the lowest risk measures to get the UK out of lockdown, according to research from the University of East Anglia.

Researchers studied the success of different social distancing measures across 30 European countries, in terms of how effective they have been at reducing the number of Covid-19 cases and deaths.

They found that closing schools, prohibiting mass gatherings and the closure of some non-essential business, particularly in the hospitality sector, were the most effective at stopping the spread of the disease.

Eastern Daily Press: Paul Hunter, professor in medicine at the University of East Anglia. Picture: UEAPaul Hunter, professor in medicine at the University of East Anglia. Picture: UEA (Image: Archant)

Enforcing the wearing of face masks in public was not found to make additional impact.

Due to the rapid response nature of the research, it has not yet been peer-reviewed.

Eastern Daily Press: The UEA study looked whether stay-home restrictions had been effective in helping stop the spread of coronavirus. Picture: Getty ImagesThe UEA study looked whether stay-home restrictions had been effective in helping stop the spread of coronavirus. Picture: Getty Images (Image: Getty Images)

But it is hoped that the findings could help policy makers decide the next steps for carefully lifting Covid-19 lockdown measures.

Prime minister Boris Johnson will review coronavirus lockdown measures with ministers today - ahead of an expected easing of restrictions from Monday.

Lead researcher Professor Paul Hunter, from UEA’s Norwich Medical School, said: “Countries across Europe have dealt with Covid-19 in different ways. We wanted to see which social distancing measures are most effective at controlling the pandemic.”

The researchers looked at the number of cases and deaths taken from daily published figures by the European Centre for Disease Control. The measures looked at the restriction of mass gatherings, the closure of schools and different types of businesses, stay at home orders and the wearing of face masks.

Eastern Daily Press: School closures had the greatest association with a subsequent reduction in the spread of covid-19 the UEA study found. Picture: Tim Goode/PA ImagesSchool closures had the greatest association with a subsequent reduction in the spread of covid-19 the UEA study found. Picture: Tim Goode/PA Images (Image: PA Wire/PA Images)

The research was carried out at UEA, in collaboration with researchers at the University of Newcastle, the London School of Hygiene and Tropical Medicine and Tshwane University of Technology in South Africa.

It is one of the first analyses that tries to determine what the most effective community scale interventions are, at least in Europe.

Eastern Daily Press: McDonalds in Haymarket, Norwich, boarded up during the coronavirus pandemic. Picture: Simon ParkinMcDonalds in Haymarket, Norwich, boarded up during the coronavirus pandemic. Picture: Simon Parkin (Image: Archant)

The study shows that imposing non-pharmaceutical measures have been effective in controlling the spread of Covid-19. But not all interventions have been equally successful.

Dr Julii Brainard, also from UEA’s Norwich Medical School, said: “We found that banning mass gatherings, closing some non-essential businesses and closing educational facilities are most strongly associated with reduced incidence after a certain lag period.

Eastern Daily Press: A taxi driver in Dereham wears a face mask amid lockdown due to coronavirus. Picture: Denise BradleyA taxi driver in Dereham wears a face mask amid lockdown due to coronavirus. Picture: Denise Bradley (Image: Copyright: Archant 2020)

“But widespread closure of all non-essential businesses and stay-at-home policies do not appear to have had a significant effect on the number of Covid-19 cases across Europe.”

Has closing schools been effective?

There has been a lot of uncertainty about whether schools and nurseries should be closed – particularly given that children seem to show mild or no symptoms.

Throat swabs from children have shown similar viral load to those in adults, yet other studies have not found evidence of children transmitting the infection to adults.

Prof Hunter said: “Our study shows that school closures in Europe had the greatest association with a subsequent reduction in the spread of the disease.

“But this study does not resolve the lack of consensus about whether children can pass Covid-19 to adults. And it does not identify which level of school closure has the most impact whether it is primary, junior, senior school or even higher education.

“It’s also important to remember that our results are based on total closure, so it is possible that partial school closures could have worthwhile impacts on the spread of infection.”

Has banning mass gatherings helped stop the spread of the virus?

Banning public and private mass gatherings has had the second greatest impact on the spread of Covid-19, the research found. These findings are backed up by past experience.

Prof Hunter said: “In the past there have been several outbreaks of other respiratory infections linked to music festivals. For example, in 2009, outbreaks of swine flu were recorded at three of Europe’s six largest music festivals, while at one point some 40pc of pandemic flu cases that season in Serbia were linked with the Exit music festival.

“How big a mass gathering may need to be to have been prohibited varied between countries so it is not clear what size of mass gathering would have been important.”

Have stay-home restrictions been effective?

The study shows stay-home policies were not associated with a decline in incidence, and actually showed a positive association with cases. As the number of lockdown days increased, so did the number of cases.

Dr Brainard said: “This result really surprised us and shows that stay at home orders may not be required to control the outbreak, provided that this does not lead to more mass gatherings.

“However there have been considerable differences in how countries have carried out stay-home policies.

“Acceptable reasons for being outdoors has varied between countries, and stay-home orders in some countries have been advisory rather than enforced by police with penalties.

“Because of this, the results for the potential of stay-home advisories may be under-estimated.”

What effect has closing businesses had?

The study found that the first wave of non-essential closures in each country had the biggest impact on the spread of infection. Those initial closures tended to be directed at businesses where people congregate such pubs, leisure centres, restaurants and venues.

Prof Hunter said: “This suggests that keeping some businesses closed, particularly in the hospitality and leisure sector, would have the most impact.

“However, we also know that while outbreaks of food poisoning are frequently linked with restaurants, outbreaks of other respiratory infections generally in the hospitality sector are fairly rare.

“The closure of other types of business, such as non-essential shops, seems to have made little impact on the spread of Covid-19.”

Would face masks help?

Wearing face masks in public was not associated with any independent additional impact, the study found. But the researchers say these results are too preliminary to reliably inform policy.

Dr Brainard said: “The use of face coverings initially seems to have had a protective effect. However, after day 15 of the face covering advisories or requirements, we saw that the number of cases started to rise – with a similar pattern for the number of deaths.

“Face coverings may even be associated with increased risk, but the data quality for this is very uncertain.

“The results on face coverings are too preliminary to reliably inform policy, but what results are available do not support their widespread use in the community.

“Wearing face covering as an intervention certainly merits close monitoring.”

What the study doesn’t tell us

It is also very hard to separate out individual intervention effects, not least because interventions were implemented in different ways and at different points in different countries.

Prof Hunter said: “We looked broadly at a range of interventions but there will be a lot of granular difference between countries. For example in Sweden schools for under 16s stayed open, but schools for over 16s, universities and colleges have been shut.

“Face covering interventions have also varied hugely between countries.

“It is important to remember that single epidemiological analyses do not prove cause and effect, especially where multiple interventions have been implemented very close to each other as in the case here.

“It is vital that we carefully monitor the future trajectory of the pandemic as restrictions are gradually relaxed across Europe, only then will we know with greater certainty what interventions were beneficial and what were not”.

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