Coronavirus: Are children at risk and do they spread it?
Coronavirus: Schoolchildren's risks of catching and spreading the disease
(3 days later)
Some children are set to go back to primary schools in England, but big questions remain about their role in the pandemic.
The announcement that some children in England are to go back to primary school on 1 June has sparked a debate over the safety of the government's plan.
Children can catch coronavirus but very rarely become seriously ill.
Though children can catch coronavirus, they very rarely become seriously ill - but it is unclear how much they might be spreading it to each other and to adults.
But it is unclear how much they might be spreading it to each other and to adults.
Here is what experts understand so far about the potential risks involved in reopening schools.
Here is what experts understand so far about young people and coronavirus.
Are children themselves safe?
Do children get sick?
Children are at extremely low risk of becoming ill from the virus, so going back to school is not putting them at risk.
It remains the case that, overall, older people are most at risk of complications from the virus.
Adults - and particularly older adults - are far more likely to be seriously ill and die from complications of the virus.
The average age of people being admitted to critical care units in England, Wales and Northern Ireland was 60 as of 24 April, an audit by a research charity suggested.
Across the UK, 0.01% of deaths were people under 15, 1% were aged 15-44 and about 75% were over 75.
"Children have so far accounted for between 1% and 5% of diagnosed Covid-19 cases, have often milder disease than adults and deaths have been extremely rare," according to Prof Adilia Warris, a paediatric infectious diseases specialist at the University of Exeter.
The median age of people with confirmed coronavirus being admitted to critical care units in England, Wales and Northern Ireland was 60 as of 15 May, an audit by a research charity suggested - meaning half were older than 60 and half were younger.
The majority were over 50 and fewer than 10% were younger than 40.
Of all diagnosed cases, children have so far accounted for between 1% and 5%, according to Prof Adilia Warris, a paediatric infectious diseases specialist at the University of Exeter. They have "often milder disease than adults" and deaths have been rare, she says.
There have been some extremely rare cases of children developing an inflammatory syndrome similar to Kawasaki disease and a possible delayed immune response to coronavirus is being explored.
Can children pass on coronavirus?
Can children pass on coronavirus?
So far they appear to be at low risk of becoming ill from the virus - but one of the missing pieces of the puzzle is how much children carry coronavirus and spread the disease to others.
This is one of the missing pieces of the puzzle about coronavirus and how it spreads.
It is still not clear how infectious people are if they have very mild symptoms or no symptoms at all - of any age.
It is still not clear how infectious anyone is if they have very mild symptoms or no symptoms at all - of any age. To understand this we would need widespread antibody testing to find out who has had the virus across the whole population.
Coronavirus is transmitted in a similar way to the flu virus - through coughing or touching objects contaminated by droplets, such as pens and door handles.
One study looking at cases in Shenzhen in China at the beginning of the year suggested children were just as likely to catch the virus, raising the fear that they were transmitting it without showing any symptoms. But since then studies have had more reassuring findings.
Keeping 2m (6ft) away from other people at all times and washing your hands before touching your face or eating food helps stop the spread of coronavirus. These preventive measures are challenging even for adults to maintain.
Studies of clusters of infections in family groups across China have concluded, based on contact tracing, that none of the infections were likely to have been introduced by children.
Whether children are spreaders or not remains "one of the many unknowns with the current coronavirus outbreak", says Prof Matthew Snape from the University of Oxford. He is beginning research into how many children and teenagers have been infected and developed immunity.
A study of a cluster of infections in the French Alps found a child who tested positive for the virus did not pass it on to any of the more than 100 people they had contact with during the time they had symptoms.
"We know from the current data that children have fewer symptoms and appear to have different transmission dynamics to adults," says Prof Saul Faust, professor of paediatric immunology and infectious diseases, from the University of Southampton and University Hospital Southampton NHS Foundation Trust.
Community studies in Iceland, South Korea, the Netherlands and Italy all found evidence children were less likely to have - or have had - the virus than adults. The Italian region studied tested 70% of its population.
"Children may possibly have shorter/fewer viral excretions from coughing or speaking," he added.
A review of the evidence by a global team of researchers concluded: "The role of children in transmission is unclear, but consistent evidence is demonstrating a lower likelihood of acquiring infection, and lower rates of children bringing infections into households."
One theory for why children generally have no symptoms or milder ones is that their lungs might contain fewer of the receptors that coronavirus uses to infect cells. But experts say there is not yet any good evidence to support this.
What about staff?
More children in schools means more teachers working, and more parents at the school gates - it's not yet clear how those extra contacts will affect the spread of infection.
Dr Jenny Harries, deputy chief medical officer for England, said that seven different "return to school" scenarios had been modelled by the government's Scientific Advisory Group for Emergencies (Sage) and the government had adopted the one estimated to give the smallest increase in the R number - the measure of how fast the disease is spreading.
It was reported that in 22 European Union countries where schools were partially reopened, there hadn't been a significant increase in cases, including among staff. These countries all opened up schools to different extents.
France did report a small uptick in cases after partially re-opening schools.
Why send primary school children back to school first?
Why send primary school children back to school first?
Government guidelines say they are starting with Reception, Year 1 and Year 6 children because:
Government guidelines say they are starting with Reception, Year 1 and Year 6 children because:
World Health Organisation (WHO) chief scientist Dr Soumya Swaminathan says that children are "less capable" of spreading the virus, and are at "very low risk" of getting ill from the disease.
World Health Organization (WHO) chief scientist Dr Soumya Swaminathan says that children are "less capable" of spreading the virus, and are at "very low risk" of getting ill from the disease.
"What we have seen in countries where schools have remained open is that there have not been big outbreaks in schools," Dr Swaminathan said.
"What we have seen in countries where schools have remained open is that there have not been big outbreaks in schools."
Should children wear masks at school?
While face coverings may help reduce the chance of spreading the disease when social distancing rules are difficult to follow, the government is not recommending their use in UK schools.
Guidance explains that young children may find it difficult to use them without assistance and that focus should be on washing hands and other good hygiene measures.
Are children immune?
One theory for why children generally have no or milder symptoms is that their lungs might contain fewer of the receptors that coronavirus uses to infect cells. But experts say there is no good evidence to support this.
And there have been reports of a very small number of children with coronavirus getting very sick and developing an overactive inflammatory immune response.
What about Kawasaki-like disease?
Scores of children in the UK, US and across Europe have been affected by a rare inflammatory disease linked to coronavirus. In a tiny number of children it can cause serious complications, with some needing intensive care.
Symptoms appear similar to Kawasaki disease - a potentially fatal syndrome that affects blood vessels - including a high temperature, low blood pressure, a rash and difficulty breathing.
The syndrome appeared to be similar to the over-active immune response, known as a "cytokine storm", seen in some adults with Covid-19. In many cases, it seems it is the body's immune response rather than the virus itself that proves life-threatening.
But these symptoms identified in children are very rare events - known to affect about up to 100 children in the UK so far - and not all of them tested positive for Covid-19.
The majority of children who have had the condition have responded to treatment and are getting better, said Prof Russell Viner, president of the Royal College of Paediatrics and Child Health.
"This shouldn't stop parents letting their children exit lockdown," Prof Viner added.
When to seek help
While children can catch coronavirus, it is rarely serious. If your child is unwell it is likely to be a non-coronavirus illness, rather than coronavirus itself.
The Royal College of Paediatrics and Child Health advises parents seek urgent help (call 999 or go to A&E) if their child is:
What about pre-existing conditions?
Underlying health conditions also play a role, regardless of age.
For example, there are about five-and-a-half million people in the UK of all ages who have asthma - and this puts you at higher risk of severe illness if you contract coronavirus.
Children with existing health conditions that put them at much higher risk of complications from coronavirus are being advised to stay at home - a protective precaution called shielding.
