Could lockdown have left children with life-long immunity problems?

As spring approaches, the UK may finally turn the corner on one of the worst winters the health service has ever seen – particularly for child sickness. There have been mysterious infections, huge waves of respiratory illness and bugs on top of bugs.

Parents will be breathing a sigh of relief. But some experts warn many of these are pandemic-related problems that may be far from over.

Professor Tracy Hussell, a director at the Lydia Becker Institute for Immunology and Inflammation, told The Mail on Sunday that lockdowns, which were necessary to prevent the spread of Covid, may have had unintended consequences for children’s developing immune systems which could affect them for some time to come.

The most recent wave of infections were expected, she says. But – while it’s too early to say – they could represent a ‘smoking gun’ for the NHS which could ‘indicate what’s ahead for that generation’.

But why?

Schools returned in September 2020 following lockdown, but many still had measures in place to mitigate against the risk of spreading Covid-19

It is well known that when Covid hit the UK, children avoided the gauntlet of common childhood illnesses. School closures, social-distancing and mask-wearing meant those infections didn’t have the usual chances to spread.

But as a result, children’s immune systems haven’t developed to fight them. In fact, the immunity of the entire population has waned.

Now, with society largely back to normal, those illnesses have returned – and there is a much bigger pool of susceptible people they can infect. This is what scientists refer to as the ‘immunity gap’.

Most experts say that next winter, once these viruses have spread through the population again, allowing immune systems to recognise the bugs and fight them off more effectively, we’ll see smaller, more normal waves of infection.

But Prof Hussell says it is possible that, for some children, it may take longer to catch up. Being infected with viruses in early life, and being vaccinated, can be ‘an education’ for the immune system, she says.

Without either – or both, as we know childhood vaccination rates fell sharply during the pandemic – children may not only continue to pick up these bugs but become sicker from them because the immune system over-reacts when it encounters them.

Prof Hussell says: ‘The very early years are important for setting your immune system. These are shaped by the pollutants, bugs and viruses we encounter.

‘If you encounter very little to trouble that immune system – as happened to children during the Covid pandemic – it ends up being rather naive, and may over-react when it comes into contact with a bug or virus later on.

‘What we don’t yet know is at what stage someone’s immune system is set. But if it’s within a window of just a few years, many children may react more severely to common infections for a long time. Could these waves of infection be a smoking gun for the NHS, a sign of what’s to come? It’s too early to say.’

If this does happen, it may represent just one of the enduring issues children are facing as a result of the pandemic.

On Tuesday, the first preliminary hearing of the independent UK Covid-19 Inquiry will be held, which will investigate the harms of key decisions the Government made during the pandemic.

Young people have, surprisingly, only recently been added to the agenda. They were initially left out of the draft scope, until Ministers bowed to pressure from campaigners, including former children’s commissioner Anne Longfield. This was despite that fact the Government’s pandemic advisory group SAGE was presented with evidence of harms to children in the autumn of 2020. Recently, more evidence has provided further proof.

Last week, an annual Government report which assesses child wellbeing found that loneliness and mental health problems have worsened, particularly among girls, while rates of eating disorders, self-harm and obesity have soared since the pandemic. Referrals for serious mental health problems such as depression, anxiety and self-harm also rose 39 per cent last year to 1.1 million.

Separate NHS Digital data shows hospital admissions for under-18s with eating disorders have risen 82 per cent to 7,719 since the year before the pandemic. Neurologists also noted an increase in the number of girls developing tics – repeated, twitching movements – which are thought to be linked to high levels of stress and anxiety.

Many children are still more than a month behind in reading and weeks behind in maths, which according to a recent National Audit Office report is putting their future earning potential at risk. Education watchdog Ofsted has found ten per cent more five- and six-year-olds than usual need support with speech and language in schools. Meanwhile, Ofsted chief Amanda Spielman has also warned of an increase in persistent school absences since the pandemic – with nearly 100,000 disappearing almost entirely from school.

Anne Longfield told The Mail on Sunday that children were ‘still paying the price’ for Covid-related school closures, ‘and potentially will be for a very long time to come’. In contrast, the impact of the Covid virus itself on most children has been limited – 141 children died from the virus, a tiny fraction of the UK total of more than 200,000 people.

However, the latest data from the Office for National Statistics suggests about 71,000 children in the UK are suffering from long Covid, which includes symptoms such as debilitating fatigue, brain fog, sleep problems and muscle pain. And as the evidence of long-term harm mounts, many experts are increasingly convinced the well-meaning measures brought in to protect children from Covid were actually worse than the disease.

The fact many different infections have spent the winter circulating at the same time – outside their normal seasonal patterns – has exacerbated the situation, scientists say. And when they coincide like this, they can cause significant problems.

Latest data from the Office for National Statistics suggests about 71,000 children in the UK are suffering from long Covid, which includes symptoms such as debilitating fatigue, brain fog, sleep problems and muscle pain

Take, for example, group A strep, a bacterial infection more commonly known as scarlet fever. There have been more than ten times the average number of cases this winter season. These aren’t always problematic and generally cause just a sore throat and flu-like symptoms. But if the infection comes after the body has just fought a virus – any one of many in circulation at the moment – the body finds it harder to fight off, says Professor Neil Mabbott, who specialises in immunopathology at the University of Edinburgh.

About 30 children are known to have died from this invasive form of group A strep.

‘It’s possible there’s piggy-backing, where a secondary bacterial infection takes hold after a virus and causes more damage,’ Prof Mabbott adds. ‘Or it may be a more serious strain. We just don’t know.’

Another unusual illness affecting children has been hepatitis, an inflammatory liver condition normally caused by a virus, alcohol abuse or other toxins. There were 274 cases of the condition in children under 16 between January and July 2022 – which led to 15 needing a liver transplant. This compares with just six cases in April 2021.

Experts believe that the condition may have been triggered by children becoming infected with two viruses at once – adenovirus, a common respiratory bug, and another called AAV2, which alone is typically harmless.

Other explanations have also been cited, including the lowered immunity which children are facing due to lockdowns, the wave of adenovirus infections in the wake of Covid measures being lifted and changes to the pattern of how viruses usually circulate.

But Prof Mabbott is not convinced of long-term repercussions for children’s immune systems.

‘It’s likely, as we move forward, things will return to a more normal, seasonal pattern,’ he says. ‘There’s no evidence for longer-term effects on the immune system.’

Arabella Skinner, a director at children’s campaign group Us For Them, said: ‘By autumn 2020, the Government knew the damage children had suffered and chose to sacrifice their wellbeing for the rest of society. We need to make sure that, in the future, any decisions regarding children and school closures must be accompanied by a proper risk/benefit analysis.

‘Knowing what we know now, can they honestly say it was worth it?’