Thirteen other children in the UK have been struck down with mysterious hepatitis which has been spotted in more than 20 countries.
There are now 176 cases of fatal liver disease in children under 10 in Britain, with the majority (128) in England.
The UK Health Security Agency (UKHSA) said it was also investigating a “small number” of suspected cases in children over the age of 10.
It came as a child in Ireland became the latest victim of the outbreak, with a second child receiving a liver transplant.
The latest fatality is believed to bring the global death toll to nine, including five in the United States and three in Indonesia. There hasn’t been one in Britain so far.
There have been around 350 cases of “severe hepatitis of unknown origin” in children registered in 21 countries since April.
At least 26 young people have needed liver transplants, according to the latest update from the World Health Organization (WHO) last week.
Experts have warned that the current cases may just be the tip of the iceberg due to poor surveillance in some countries.
Scientists are puzzled as to the cause of this unusual disease, but the main theory is that it is triggered by a group of viruses that normally cause the common cold.
There have been around 350 cases of ‘severe hepatitis of unknown origin’ in children registered in 21 countries since April
Ireland’s Health Service Executive (HSE) did not reveal the age of the latest victim, but said its cases involved children under 12.
Since March, six children have been hospitalized with hepatitis in Ireland, which the HSE says “is more than you would usually expect over this period”.
The HSE said none of the cases in Ireland were linked and they were not linked to any of the patients in the UK. None had Covid either.
Ireland is working closely with the WHO and colleagues in the EU and Britain to identify the cause of the illnesses.
Parents are advised to see their GP if their child develops symptoms of hepatitis, including pale gray stools, very dark urine or yellowing of the eyes and skin.
Common viruses that cause hepatitis: hepatitis A, B, C and E viruses; have not been detected in any of the reported cases worldwide.
In its latest update on May 9, the WHO said there had been 348 probable cases of hepatitis of unknown origin since the first was reported in Scotland in April.
All of the cases are in children aged 11 months to five years and ‘many’ have tested positive for the adenovirus.
The virus has not yet been identified in the analyzed liver tissue samples “and therefore could be a coincidence rather than a causative factor”, the WHO said.
In new guidelines this week, the Centers for Disease Control and Prevention (CDC) in the United States told doctors treating children with hepatitis to take liver samples for testing.
US STATES WITH CASES: The map above shows the 26 states that have confirmed or suspected cases of hepatitis according to the CDC. Massachusetts and Hawaii became the 25th and 26th states to reveal they are investigating suspected cases of the disease (yellow), with Puerto Rico also reporting at least one case.
According to an analysis, three-quarters of children with hepatitis in the UK have tested positive for adenoviruses.
Scientists are investigating whether a mutated strain of adenovirus has evolved to become more severe, or whether a lack of social mixing during the pandemic has weakened children’s immunity. They cannot rule out that an old Covid infection is involved.
In a bizarre twist last week, UK health chiefs are also investigating whether ‘dog exposures’ are to blame.
The UKHSA said last week that a “high” number of UK children with hepatitis came from families with dogs.
Officials have not explained how the dogs could potentially be to blame, but they are known carriers of strains of adenovirus.
However, health officials have ruled out the Covid vaccine as a possible cause because the majority of sick British children have not been vaccinated due to their young age.
Hepatitis is generally rare in children, but experts have already spotted more cases in the UK since January than they would normally expect in a year.
Q&A: What is the mysterious global hepatitis epidemic and what is behind it?
What is hepatitis?
Hepatitis is an inflammation of the liver that is usually caused by a viral infection or liver damage caused by alcohol consumption.
Some cases resolve on their own with no lingering problems, but a fraction can be fatal, requiring patients to need liver transplants to survive.
What are the symptoms?
People with hepatitis typically experience fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, pale stools, and joint pain.
They can also suffer from jaundice – when the skin and the whites of the eyes turn yellow.
Why are experts concerned?
Hepatitis is generally rare in children, but experts have already spotted more cases in the current outbreak than they would normally expect in a year.
The cases are of “unknown origin” and are also serious, according to the World Health Organization. It has caused up to two deaths and 18 liver transplants.
What are the best theories?
Experts say the cases may be linked to adenovirus, commonly associated with the common cold, but more research is ongoing.
This, in combination with Covid infections, could be behind the spike in cases.
Adenovirus reported by WHO was detected in at least 74 of the cases. At least 20 of the children have tested positive for coronavirus.
British experts investigating the wave of illness believe the endless cycle of lockdowns may have played a contributing role.
The restrictions may have weakened children’s immunity due to reduced social mixing, leaving them at increased risk of adenovirus.
This means that even the “normal” adenovirus could be the cause of the serious consequences, because children do not react to it as they did in the past.
Other scientists said it may have been the adenovirus that had acquired “unusual mutations”.
This would mean that it might be more transmissible or better able to circumvent children’s natural immunity.
New Covid Variant
UKHSA officials included “a new variant of SARS-CoV-2” in their working hypotheses.
Covid has caused inflammation of the liver in very rare cases during the pandemic, although these have been in all ages rather than isolated in children.
The CDC noted that environmental triggers are still being researched as possible causes of illnesses.
These could include pollution or exposure to particular drugs or toxins.