There have been a total of 222 cases of hepatitis in children aged 10 and under in the UK, the UK Health Security Agency (UKHSA) confirmed on 27 May. Of these, 11 children have needed a liver transplant. No children in the UK have died due to the disease.
Scientists do not yet know the cause of the sudden surge in cases of child hepatitis – an illness that sees the liver inflamed and/or injured, leading to gastrointestinal symptoms like diarrhoea and vomiting. However there are several hypotheses among the medical community and in the general public.
Some have speculated as to whether vaccination for COVID-19 in children could have caused hepatitis, however there is no evidence of any link between the jabs and the disease. Globally, 75.4 per cent of cases have been found in children under five years of age, who are too young to have received the vaccine.
Due to the sudden onset of hepatitis, research is still ongoing to confirm the cause, or causes, but some of the countries that have seen cases have also reported an increase in adenovirus infections, a common type of virus that can cause illnesses such as colds, fevers, pneumonia, and diarrhoea. In the UK, testing found that 72 out of 84 children with hepatitis also had an adenovirus infection.
No connection between the surge and one geographic area or common factor (such as particular foods or animals, travel or toxin) has been identified.
At the time of writing, a total of 650 probable hepatitis cases have been reported by the World Health Organization (WHO), from 33 countries around the globe. There have been nine deaths attributed to child hepatitis since the sudden rise was reported on 5 April, and the WHO say at least 38 liver transplants have been performed.
We spoke to liver immunologist Dr Zania Stamataki to find out what scientists know about the rise of child hepatitis.
What is hepatitis?
The word hepatitis means inflammation of the liver, and there is no one cause. A patient might have been infected with a virus that caused liver inflammation, or they might have consumed a toxin that inflamed their liver. Some people might get hepatitis because they have an autoimmune disease that causes their immune system to attack their own body, leading to inflammation.
“In fact, a lot of the cases of hepatitis that we are getting nowadays are because of our high fat diet; that injures the liver as well,” said Stamataki.
But the language around this recent increase in child hepatitis cases can cause confusion as to its source, said Stamataki.
“When you read things like ‘hepatitis outbreak’, it might imply that its definitely caused by an infectious agent. The way we’re talking about it, a lot of people can mistake hepatitis for a viral illness. But actually, liver inflammation can occur from multiple different aetiologies.
“So. because we don't know [the cause] yet, it's better if we use language that describes this as a disease of unknown origin.”
Is hepatitis serious in children?
In cases of acute, short-term hepatitis, the inflammation usually resolves itself quickly.
“The liver is a tremendous organ. It's our biggest internal organ and it's the only one that has the ability to grow back,” said Stamataki. “You can cut a healthy liver and it will grow back and regenerate to the size that it needs to support your body.”
It’s not uncommon for someone to have mild hepatitis without ever recognising any symptoms. But, even if the damage to the liver is broader and causes more symptoms, the hepatitis clears up quickly, particularly in children. If the cause of the hepatitis is a virus, such as the common cold-causing adenovirus, the liver will usually recover as soon as the virus has gone away.
In the UK, babies are vaccinated against one certain type of viral-induced hepatitis as part of their regular vaccination programme.
What are the symptoms of child hepatitis?
Symptoms of child hepatitis to look out for are tummy aches and pains, diarrhoea and vomiting, and jaundice – where the skin and the whites of the eyes appear yellow.
“These are clues that something is happening in the liver,” said Stamataki. “If this occurs, you go to the doctors’ and they take a blood test, looking for liver enzymes. If they're found to be elevated, that means that there's been some damage into your liver.”
According to the NHS, symptoms of acute hepatitis can also include things like muscle and joint pain, a high temperature, loss of appetite, and dark urine.
Can a child recover from hepatitis?
Most instances of hepatitis resolve themselves quickly and do not need treatment.
However, the newly identified cases are linked to more severe hepatitis, requiring hospitalisation and treatment. So far, 12 per cent of children with this severe, sudden onset hepatitis have needed a liver transplant globally.
How many children have hepatitis?
As of 27 May, 650 children worldwide have been reported to have severe hepatitis. At this point in the year, doctors would not expect to see this many cases.
However, occurrences are still rare. Of the roughly 8.7 million children under the age 10 in the UK, there are 222 cases currently under investigation by UKHSA. Of these, there are 158 children living in England, 31 in Scotland, 17 in Wales and 16 in Northern Ireland.
“This is a very, very rare disease. So, as a mum, I’m not hugely concerned,” said Stamataki. “But as a viral immunologist, it is raising an eyebrow, because the incidence of these cases are higher compared to pre-pandemic levels.”
It could be that more children have had hepatitis by the same cause as with the severe cases, but that their symptoms were mild and their recovery quick, so they went unnoticed, said Stamataki.
What is causing the new cases of child hepatitis?
There are several hypotheses for what is causing the sudden rise in child hepatitis. It could be due to an infection with a virus, that then damaged the liver. This infection could have occurred quite a while ago, causing damage to the liver that just hasn’t resolved, Stamataki said.
One possible cause being investigated by researchers is a particular type of virus called adenovirus 41, which can cause cold-like symptoms but also diarrhoea and fever.
“Adenovirus 41 has been identified in some of these children… and it could be that it's related [to the hepatitis onset], but it could be that it's completely unrelated to these cases, because adenoviruses currently circulating as with other seasonal viruses [in the general population].”
“Now, adenovirus 41 previously has not really been linked to liver injury… So it is unusual that adenovirus 41 could be causing this,” said Stamataki.
Studies are ongoing to investigate the possible cause of the rise in cases, with some looking at the immune response, genetics and rates of adenovirus within hospitals.
Is the increase in hepatitis cases due to COVID-19 lockdowns?
Some have suggested that the sudden rise in cases could be due to COVID-19 lockdowns, as children had not been exposed to as many viruses and infections that have enabled them to build up their immune systems.
“It’s an interesting hypothesis,” said Stamataki. “Children need viral infection over the years to build up their immunity to incoming viruses. But this still doesn't explain why only a handful of those children had severe disease, and how this has affected the liver.”
Again, of the 8.7 million children affected by lockdown, only 222 hepatitis cases have been reported so far – an occurrence of around 0.0026 per cent.
Could the COVID-19 virus have caused hepatitis?
Health officials have said that around 15 per cent of UK cases were positive for coronavirus when they were admitted to hospital. However, as levels of COVID-19 were high in the general population at that time, it would not be unexpected for the children to test positive.
The UKHSA are looking into whether infection with COVID-19 could be linked to severe hepatitis.
“Before the pandemic, cases of sudden onset hepatitis were never linked to coronaviruses,” said Stamataki. “But SARS-CoV-2 is a new virus, so we're only starting to understand how it works. It's possible that the virus affects cells and organs in different people differently, and we know that it can take a little while for the body to recover [sometimes resulting in cases of long COVID].
“The question is, with so many thousands of children are getting COVID at the moment, why are these children getting liver failure? I suspect that it is more than one thing causing this liver injury that's difficult to recover [from].”
How can I protect my child from hepatitis?
The NHS recommends parents engage in good hygiene practices, such as supervising young children as they wash their hands, to prevent infections that can cause hepatitis.
Parents are encouraged to see their GP if their child has hepatitis symptoms, including jaundice. Any child experiencing vomiting and diarrhoea should stay at home and only return to school or nursery once 48 hours have passed without these symptoms.
"It’s important that parents know the likelihood of their child developing hepatitis is extremely low," said Dr Renu Bindra, Senior Medical Advisor at UKHSA. "However, we continue to remind everyone to be alert to the signs of hepatitis – particularly jaundice, look for a yellow tinge in the whites of the eyes – and contact your doctor if you are concerned."
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