Children’s hepatitis outbreak linked to lockdown

Infants may not have been exposed to viruses because of restrictions during pandemic, says UK health chief

LOCKDOWN and social distancing have been linked by health chiefs to a surge of hepatitis cases in young children.

Officials said a lack of exposure to common infections during children’s formative years because of pandemic measures may be fuelling a global outbreak of the deadly liver disease.

Some 114 cases of “acute hepatitis of unknown origin” have been reported in Britain since the first spate was detected in Scotland less than four weeks ago.

UK health officials said they had detected as many cases in the past three months as they would normally expect to see in a year, with the vast majority involving children aged five and under.

They added that three quarters of cases in Britain have been linked to adenoviruses, a viral infection that usually causes the common cold. If someone’s immune system cannot fend off the virus, it can develop into hepatitis.

Dr Meera Chand, who is heading the UK Health Security Agency’s (UKHSA) investigation, said the virus might be hitting young children hardest because lockdown restrictions meant they were not exposed to it in their early years.

This suggests “a susceptibility factor”, she said, such as a lack of exposure for young children whose early years coincided with the pandemic.

Speaking at the European Congress of Clinical Microbiology and Infectious Diseases in Lisbon yesterday, she said: “I think our leading hypothesis … would probably be that we have a normal adenovirus circulating. We may not have seen as much of it as we have for the past couple of years. But we have a co-factor affecting a particular age group of young children, which is either rendering that infection more severe or causing it to trigger some kind of an immunopathology.

“Co-factors include a lack of prior exposure of that particular age group during the formative stages they’ve gone through during the pandemic.”

Experts have previously raised concerns about the long-term impact of lockdown on children’s education and physical and mental health. However, this is the most serious potential health complication to have emerged so far.

In total, 169 children have been diagnosed in 12 countries since last October, the World Health Organisation has announced. But liver experts said these cases might be the “tip of the iceberg” as some symptoms could be missed.

Around the world, 17 children – including 10 in the UK – have required liver transplants, while one child has died abroad. In the UK, the average age of children involved is three, with twothirds of cases involving those aged between three and five.

Detailed data for England show that in 53 per cent of cases the children have recovered.

While rates of adenoviruses fell to almost nothing during lockdown, between 200 and 300 cases are now being reported weekly, compared with rates of between 50 and 100 per week in a normal year, experts said.

There are also concerns that a common adenovirus could have mutated to become more severe.

UK health officials have ruled out the Covid vaccine as a possible cause.

None of the affected children aged 10 and under in Britain had been vaccinated, officials said. Scientists say there were no links between the children, who were not in contact with one another, or with travel.

Officials are examining whether current or prior infections with Covid are playing a part. One in six of the children admitted to hospital tested positive on admission, but officials said this was not unexpected at a time when background levels in this group were high.

They have not ruled out other environmental factors such as a poison or environmental exposure, but said this

seemed less likely, given the spread of cases around the world.

Aikaterini Mougkou, from the European Centre for Disease Prevention and Control, said the emerging trends were “really worrying” and appeared to reflect a rise in cases of adenoviruses after restrictions were eased.

“Because of the physical distancing restrictions during the pandemic, there were only a few cases in 2020 and 2021. But there was the high circulation in the beginning of 2022, especially in the age group under five,” she said.

Thirteen cases have been detected in Spain, 12 in Israel and 11 in the US, with cases also found in Denmark, Ireland, the Netherlands, Italy, France, Norway, Romania and Belgium.

Prof Deirdre Kelly, an expert in paediatric hepatology at Birmingham Women’s and Children’s Hospital, said the number of cases identified might continue to rise. She said: “I do think that what we’ve seen so far may be the tip of the iceberg because unless they’re yellow [with jaundice], it probably doesn’t come to medical attention. The other early symptoms are tummy ache, vomiting and diarrhoea – which aren’t very specific in children.”

While the latest figures are “huge” compared with normal trends, she said it was possible that some cases could “fade out” after spring as there is normally a bump in hepatitis infections of unknown cause at this time of year.

“We may see it fade out, hopefully as children build up their immunity. What will be really interesting is if there’s something different about the children who have got it, and that’s where the genetic work will come through.”

Dr Chand, the UKHSA’S director of

‘What we’ve seen may be the tip of the iceberg as unless they’re yellow, it doesn’t come to medical attention’

clinical and emerging Infections, said: “Information gathered through our investigations increasingly suggests that this rise in sudden onset hepatitis in children is linked to adenovirus infection. However, we are thoroughly investigating other potential causes.

“Parents and guardians should be alert to the signs of hepatitis (including jaundice) and contact a healthcare professional if they are concerned.”

She added that children with vomiting and diarrhoea should not return to school or nursery until 48 hours after symptoms have stopped.