Scientists say the reopening of schools in England, both primary and secondary, is ‘unlikely’ to lead to a second wave of coronavirus infections.
The gradual reopening of schools, starting with primary schools, wouldn’t drive the average coronavirus transmission rate above one, infectious disease experts claim.
Their mathematical modelling study shows that the impact of less social distancing on the part of adults would in fact be more likely to cause a ‘second wave’.
As part of a phased return to schools in effect since Monday, the government is allowing pupils in reception, year one and year six to return to classes.
While this policy could slightly raise the ‘R’ number – the average amount of people that one infection person would pass the virus on to – it’s unlikely to push it above one, the research team claims.
The act of reopening workplaces, pubs and restaurants and gyms would ‘exacerbate’ any potential impact of reopening schools, they say.
The gradual reopening of schools, starting with primary schools, is unlikely to lead to a second wave of infection, according to new mathematical modelling of the COVID-19 outbreak from University of Warwick researchers. Primary schools started to get up and running in England this week, with reception, years one and years six the first to return. Pictured, Stoneriase School near Carlisle
The experts support a ‘cautious’ reopening of schools along with close monitoring of the reproduction (R) number, they conclude from their research at the University of Warwick.
‘Our work indicates that the current policy of reception, year 1 and year 6 children returning to school is likely to result in a small increase in the reproduction number,’ said Professor Matt Keeling, director of the University of Warwick’s Zeeman Institute, which works to bring ‘sophisticated mathematics to challenges in biological sciences’.
‘In isolation this is unlikely to push R above 1 but there still remains uncertainty over the consequences of other recent changes that have relaxed the lockdown.’
In the UK, cases of COVID-19 – the disease caused by the SARS-CoV-2 strain of coronavirus that has killed 50,000 people in the country so far – have been declining since mid-April.
‘R’ RATE: THE AVERAGE OF SECONDARY INFECTIONS
The reproduction number (R) is the average number of secondary infections produced by one infected person.
It is a value that represents how many people one sick person will, on average, infect if the virus is reproducing in its ideal conditions.
An R number of one means that on average every person who is infected will infect one other person, meaning the total number of new infections is stable.
If R is two, on average, each infected person infects two more people.
If R is 0.5 then on average for each two infected people, there will be only one new infection.
R can change over time – for example, it falls when there is a reduction in the number of contacts between people, which reduces transmission.
The R number in the UK is updated on the government’s website and currently is just below one.
Since the decline there is evidence to suggest the government’s oft-mentioned ‘reproduction number’ – designed as a measurement of the severity of the disease – has dropped below one.
An R number of one means that on average every person who is infected will infect one other person, meaning the total number of new infections is stable, according to the government.
If R is greater than one, the epidemic is generally seen to be growing, while if R is less than one the epidemic is shrinking.
With a shrinking epidemic, a multi-phase relaxation plan for the country to emerge from lockdown has been laid out, starting with the return to school on Monday.
However, the decision has divided parents, with many expressing concerns that their child could become infected and bring the contagion into the family home.
Professor Keeling and his team say a range of sources suggests children are only mildly affected by the disease in general and have low mortality rates, although ‘there is less certainty regarding children’s role in transmission’.
The University of Warwick team compared different strategies for opening schools in England from June 1, focusing on particular year groups and the ‘epidemic consequences’.
They investigated a range of school re-opening scenarios, including the current policy, as well as children returning in ‘half-sized classes’ and all primary and secondary school children returning to full time education.
The team used a detailed mathematical model, calibrated against data on the age distribution of cases, as well as the changing numbers of those being hospitalised and dying as a result of the disease.
From this, they were able to forecast the impact of school re-opening upon the R number and the expected increase in the number of cases of COVID-19 as a result of the return to schools.
They found that reopening schools in a way that allows half-sized classes or focuses on the return of younger children is unlikely to push the R rate above one.
Less social distancing on behalf of the rest of the population, enabled by the reopening of pubs and restaurants, will generally have fare greater effects than reopening schools, the researchers said
Reopening secondary schools, meanwhile, would lead to larger increases in coronavirus transmission than only opening primary schools because older children have more social contacts, leading to increased mixing and transmissions.
Reopening both primary and secondary could push the R rate above one in some regions of the country, they say, although the opening of schools alone is unlikely to push the R rate above one.
The impact of less social distancing on the part of the rest of the population that don’t go to school would have ‘far larger effects’.
Reopening workplaces, leisure facilities such as gyms and pubs and restaurants would exacerbate the impact of reopening schools and likely drive the R rate above one, they warn.
The government is set to ease more of its lockdown restrictions as the R rate falls, ending with the reopening of pubs, clubs and restaurants
While any reopening of schools would result in increased mixing and infection above children and the wider population, reopening schools alone would likely keep R under one.
While there would likely be more infections as a result of opening schools, it shouldn’t cause a second wave and could leave an open path to a full emergence from lockdown.
‘It is important to note that any increase in mixing will likely lead to some increase in COVID-19 cases, even if the value of R remains below one,’ said Assistant Professor Dr Louise Dyson at the university’s Mathematics Institute.
A reintroduction of lockdown measures should be considered if any significant rise in cases is seen after any other social distancing rules are relaxed, they say.
Limited data on COVID-19 in children also means school reopening and its effects should be carefully monitored.
The full study has been published on the university’s website.