If there is any blessing when it comes to Covid-19, it's that our children aren't dying. One thing we've learnt in the past four months (that's how recent it is) is that Covid-19 is mainly a disease of older people. The numbers behind it tell us that children are largely being spared.
One number when it comes to children, however, is striking. This is a virus that has put one-third of the world's population into quarantine. Unprecedented in human history. And a major part of that quarantine is keeping children home from school - 1.1 billion children are currently being kept out of school. This has never happened before, not even during World War II, so Covid-19 breaks yet another record.
And in spite of all the effort being put into home schooling using technology, there is evidence that teachers working remotely with their pupils can provide 40pc of the education that would normally be provided. Many fear that the most vulnerable are being left behind. Some countries are carefully reopening schools. These include China, Taiwan, Germany, Sweden, Denmark and Norway.
Why close schools?
Why were schools closed, if children don't especially get sick with Covid-19? There was a fear that children might be 'super-spreaders' - but the science tells us this is not the case.
Does the science also tell us that schools in Ireland should begin to reopen?
It's perfectly understandable that once the virus began to spread, parents worried about their children. We now know there was no need to worry too much. An analysis of almost 80 studies by child healthcare experts has concluded that the vast majority of children who have been infected either show no symptoms at all, or very mild symptoms and recover. Mercifully, deaths have been very rare.
It's not fully clear why this is. Ideas include children having a stronger innate immune response to the virus. Innate immunity is like a shield against germs. It's a bit like the wall with all kinds of sensors to detect different germs including viruses. Children may have more of these sensors and can mobilise them more quickly than in older people.
It has also been suggested that children have less ACE2, the lock that the virus needs to open to get inside the cells it infects. Another possibility is that childhood vaccines offer some protection. The measles vaccine was shown to possibly protect against SARS. The BCG vaccine has generated much interest as a possible protector against Covid-19 and many millions of children have been vaccinated with it. These vaccines may be strengthening their defences. A final possible explanation is that children get more colds from other Coronaviruses which protect against Covid-19. Overall, this is good news.
But what about whether children can spread Covid-19? The evidence shows that they can, but at no higher a rate than grown-ups. Part of the fear here was that Covid-19 might be like flu, which children spread more than adults. Respiratory illnesses love children, most likely because of all the coughing, sneezing and spitting going on at close quarters in school. Children are more likely to catch flu when compared to adults, who have some protection from previous infections. They are also in contact more with other children from whom they might catch flu, which would justify the closing of schools.
Studies have shown, however, that children are less prone to infection with Covid-19 compared to adults. A study of the Italian town of Vo examined the entire population of around 3,000 people. No child under 10 was infected, comparedwith 3pc of the population as a whole.
Another study in Holland of 2,000 people revealed that the rate of infection in adults was twice that in children. And as ever, any children infected had a very mild disease.
Several studies have been carried out to estimate how many people caught Covid-19 from children compared to adults. One study found similar infection rates, while another showed less infection from children.
Studies in Iceland and Holland have revealed that children rarely infect adults, and the European Centre for Disease Prevention and Control has issued a statement saying that child-to-adult transmission 'appears to be uncommon'.
It's still not clear whether the closing of schools was an important factor in the slowing down of the spread of Covid-19, however, as some of these studies were done after schools were closed. We may well find out when schools start to reopen, but it will be difficult to disentangle the role of schools compared with other measures should we see a second surge.
This leaves us with a clear scientific basis for stating children are no more responsible than adults for spreading infection, and may in fact be less responsible. It was outrageous to hear of parents being prevented from bringing children into shops, and of insults being thrown at children or their parents. Hopefully this just reflects the generalised fear people have about Covid-19. The science now tells us there is no need to be afraid of children when it comes to catching it.
Should we reopen schools?
We are weighing up the economic damage being done by the lockdown (which has a health cost), against saving the lives of the vulnerable. We now need to weigh up the damage being done to our children by keeping them at home (and the economic damage of parents having to stay home to mind them), against the risk of the virus spreading again and targeting the vulnerable.
Studies show that when children were kept home from school (during storms in the US, or during the 2014-15 Ebola outbreak in West Africa, or during a two-month teacher strike in Belgium in 1990), children performed less well in education later in life. School closures have been shown to affect younger children most, who need more guidance and supervision. A worrying study in Norway concluded that school closures there cost the economy €160 for every day the school is closed per child - because of decreased parental productivity in the economy and lower earning potential for the children later in life. Less well-off children are predicted to suffer most, because of less access to online resources and difficult living circumstances.
Some countries have tried to lessen the impact. Finland only started distant learning when it concluded that almost every school child could take part. South Korea gave teachers time off teaching to allow them to adapt to new teaching methods. And when it comes to reopening, measures are in place to ensure social distancing and hygiene are maintained, and they may even provide transport for children to get to school.
Denmark has focused on the very young and those who have to sit final school exams, because the impact on them is greatest. Germany is also ensuring final-year students can sit their exams. If the science supports the conclusion that these two ends of the educational spectrum might suffer the most, shouldn't Ireland do the same?
The jury is still out on whether opening schools fully might lead to an increase in viral transmission. But shouldn't we think about the pupils who might suffer most from their schools being closed and take the risk on them going back to school? We want to make sure the brave new post-Covid-19 world of the future is as good as we can make it - if not better than before.
Opening schools is one way to do it. Otherwise we might be damaging the future prospects of our children. And who wants to do that?
Luke O'Neill is professor of biochemistry in the School of Biochemistry and Immunology at Trinity College Dublin