The World Health Organization has warned that young people across Europe could trigger coronavirus spikes, with the continent on the brink of a second wave.
The organization's European director said there is a higher proportion of new cases among young people.
But is that the case in the UK? And if there are higher rates among young people – especially if it is documented that young people overall are less affected by COVID-19 – is this cause for concern?
Dr. Hans Kluge did not go to specific countries when he told Wednesday's BBC Radio 4 program today: "More and more countries are experiencing localized outbreaks and a resuscitation in cases … This is a result of a change in human behavior.
"We have received reports from multiple health authorities about a higher proportion of new infections among young people, so for me the call is loud enough to rethink how young people can be better involved."
His warning comes at a time of growing concern about the risk of communities being reinfected by people returning from vacation hotspots. Some of them have been accused of observing less social detachment than might be the case at home, as well as reports of street parties after the closure and raves.
The European Center for Disease Prevention and Control, which collects data on coronavirus infection rates across Europe, has inconsistent information on the increase in rates between different age groups.
Britain is one of several European countries that publish data on the number of people of different ages who have tested positive, but not all.
Austria, Denmark, Slovakia, Spain, Latvia and Estonia publish infection rate figures between different age groups, and indeed some of their graphs show slightly increasing rates among younger groups.
In Belgium – which is said to be on the verge of a second wave – there are no obvious signs of a clear trend among young people in the other Baltic and some Scandinavian countries.
Exceptions where clear trends can be observed are Luxembourg – which is currently experiencing the worst outbreak in Europe – and Croatia, where the incidence in young groups is increasing significantly.
However, Germany, France and Italy – the largest countries in the EU – have not provided the ECDC with statistics on the prevalence of COVID-19 in different age groups for a few months, if at all.
In the UK, Public Health England has been publishing infection rates for different age groups for several months.
The numbers show that infection rates were highest in older groups in the majority of pandemics.
However, the graph is deceptive because the effects of loosening the lock are difficult to see when so many people aged 65 and over were affected in earlier stages.
A look at recent figures suggests that at least infection rates among young people in England are becoming more important.
Excluding those over the age of 85, the 15- to 44-year-old age group currently has the highest infection rate of all age groups – almost one and a half times the next higher group.
And rates are rising – albeit slowly and only for the two weeks before the last weekly PHE monitoring report.
But how do we know if young people are to blame if the PHE numbers only look at an age group as big as the 15 to 44 year olds?
Additional data suggesting that young adults may have the highest infection rates were recently provided by a pre-print study by Imperial College London, which found that out of around 120,000 swabs collected in England in May, the highest infection rates were found in the 18-24 years.
Why is that so bad? Especially when countless studies have shown that young people are generally much less likely to die if they become infected with the virus.
Experts say there are ramifications and they could get worse.
While young people often take the disease less seriously, they can still take a form that has a lasting impact on their health.
The greater risk is for others in the community – and redistribution within the community will lead to a further increase in deaths among vulnerable groups.
Dr. Jeremy Rossman, a lecturer in virology at the University of Kent, told Sky News that it could be worse than official figures suggest, as many younger people – who are less affected by the virus – are not tested.
Because their symptoms are mild, they never appear in figures from Public Health England, but they can still be passed on to others.
He said, "This rate in the healthy young adult population is actually underestimated because … the tests are skewed … and everyone, regardless of symptoms, is not tested."
A study of the rise in coronavirus cases in Florida, which has seen thousands of new infections every day for the past few weeks, found that the group had an earlier rate of infection than that of 20-24 year olds.
The graph's curves show how the number of cases increased in the next oldest infected group and then in the next oldest, etc. as soon as the cases began to increase between 20 and 24 years.
According to researchers, this is exactly what is going to happen in some European countries and would be expected in the UK if rates went up among younger people.
Studies have shown that younger age groups have higher contact rates – that is, they hit more people than others in older age groups – and are therefore more likely to catch the virus and spread it to others.
Yuliya Kyrychko and Dr. Konstantin Blyuss, a math reader at the University of Sussex, examined the spread of COVID-19 in the South Sussex region and found that this was exactly what happened in the earlier phase of the pandemic – a younger age structure was spreading from Brighton Environments with older age structures.
Dr. Kyrychko said: "Younger people tend to socialize, go to clubs, bars and restaurants and try to have as much fun as possible.
"Vulnerable and elderly people will still shield. In a way, younger people are not so interested in it. They are not afraid in the sense that at such a high rate, it does not cause them to die.
"So these people will be sick earlier and then … it will obviously go into the next age group and the next age group and then it will go on and on and on."
Dr. Rossman said the reason is that young people are interpreting the messages they receive so that they are less at risk and respond to the end of the ban.
"The virus is now not suddenly affecting another population," he told Sky News. "It’s like we’ve had some very strong news about protecting older and vulnerable people for some time … there’s a consistent message saying that younger people are at much less risk … and I believe that There's this setting that says, "I'm locked up all the time during the lockout. The pubs are finally open. I want to go out. "And that's exactly what we see.
"At the same time, it is not unexpected that there is a significant decrease in compliance with safe precautions such as physical distance, face covering, and adequate hand hygiene."
The experts say that more needs to be done to get the message across to young people.
Dr. Rossman added: "Germany was one of the first countries where the shift to a healthy young adult population showed the highest positive rate. This correlated with a lower precautionary rate. They saw this very early in the pandemic. And now we see that in Great Britain.
"We have to increase the precautions. We have to reduce the transmission in this age group. We have to change the framework and say that most cases are mild because many cases are incredibly serious and can affect any age group. That is one aspect that we do to have." must be news. "