Hepatitis is not rare in children. If fact, we have several vaccines that protect kids from viral hepatitis. What is rather uncommon is to have a prolonged outbreak of severe hepatitis, sometimes leading to liver failure, with no known cause.
Hepatitis of Unknown Cause in Children
And that is what we have been seeing since October 2021, when five children with hepatitis of unknown cause were first identified.
“A possible association between pediatric hepatitis and adenovirus infection is currently under investigation after subsequent laboratory testing identified adenovirus type 41 infection in several cases.”Clinical Guidance for Adenovirus Testing and Typing of Patients Under Investigation
Since those first cases, at least 180 children with hepatitis have been identified in 36 states.
Cases (at least 276) have also been reported in Austria, Belgium, Cyprus, Denmark, Greece, Ireland, Italy, the Netherlands, Norway, Poland, Portugal, Republic of Moldova, Serbia, Spain, Sweden, and the United Kingdom.
“Many cases reported gastrointestinal symptoms including abdominal pain, diarrhoea and vomiting preceding presentation with severe acute hepatitis, and increased levels of liver enzymes (aspartate transaminase (AST) or alanine aminotransaminase (ALT) greater the 500 IU/L) and jaundice. Most cases did not have a fever.”Multi-Country – Acute, severe hepatitis of unknown origin in children
We also know that:
- affected children have ranged in age from 1 month to 16 years, with a mean age of two years
- while most children have recovered, at least 29 children have required a liver transplant, including 15 in the United States (551 pediatric liver transplants were done in the US in 2019…)
- at least six children have died, include five children in the United States
- adenovirus has been detected in many of the cases
- although a current SARS-CoV-2 infection has not been detected in many children, serology for past infection was not in many cases
- some of the cases had a SARS-CoV-2 and adenovirus co-infection
- the vast majority of affected children did not receive COVID-19 vaccination
So is adenovirus causing these kids to get sick?
“While adenovirus is currently one hypothesis as the underlying cause, it does not fully explain the severity of the clinical picture. Infection with adenovirus type 41, the implicated adenovirus type, has not previously been linked to such a clinical presentation. Adenoviruses are common pathogens that usually cause self-limited infections.”Multi-Country – Acute, severe hepatitis of unknown origin in children
While suspicious, since so many of the kids had an adenovirus infection, adenovirus infections don’t usually cause severe hepatitis. And they have not detected adenovirus in the liver of affected children.
That leaves us waiting for the experts to continue doing their investigations.
Can you do anything else to protect your kids from hepatitis?
And while there is no publicly available adenovirus vaccine (there is one available for folks in the military), since one theory is that these cases of severe hepatitis could be caused by a “SARS-CoV-2 superantigen mechanism in an adenovirus-41F-sensitised host,” then getting vaccinated to prevent that SARS-CoV-2 infection could be a good idea.
“One hypothesis suggests the damage is being done by adenovirus, a common childhood infection that normally causes coldlike symptoms and could be treated with an antiviral drug. Another suggests the cause is a rogue immune response to previous infection by SARS-CoV-2—which could be treated with immune-suppressing drugs such as steroids. A third hypothesis proposed earlier this week brings them together, suggesting adenovirus infection forms a destructive partnership with SARS-CoV-2 that sets the immune system loose on the liver.”What’s sending kids to hospitals with hepatitis—coronavirus, adenovirus, or both?
While it might not protect them from this kind of hepatitis, it certainly wouldn’t hurt and has the added benefit of protecting your child against COVID-19!
Hepatitis of Unknown Cause in Children Hype or Hazard?
While certainly a hazard to the kids who get sick and go on to develop severe hepatitis, this is still fortunately very rare.
“It’s important to note that severe hepatitis in children remains rare. However, we encourage parents and caregivers to be aware of the symptoms of hepatitis – particularly jaundice, which is a yellowing of the skin or eyes – and to contact their child’s healthcare provider with any concern.”Update on Children with Acute Hepatitis of Unknown Cause
If you are getting worried, keep in mind that worldwide, even as cases are on the rise, only about 500 children have been affected so far and only a small percentage of them have had severe disease.
And most have recovered.
More on Hepatitis of Unknown Cause in Children
- Are More People Dying of Viral Hepatitis?
- What to Do If Your Child Is Exposed to Hepatitis A
- What to Do If Your Child Is Exposed to Hepatitis B
- Don’t Skip Your Baby’s Hepatitis B Shot
- CDC – Children with Hepatitis of Unknown Cause
- CDC – Clinical Guidance for Adenovirus Testing and Typing of Patients Under Investigation
- CDC – Clinical Recommendations for Adenovirus Testing and Reporting of Children with Acute Hepatitis of Unknown Etiology
- CDC – Children with Acute Hepatitis of Unknown Etiology: Persons Under Investigation
- WHO – Multi-Country – Acute, severe hepatitis of unknown origin in children
- CDC – Updated Recommendations for Adenovirus Testing and Reporting of Children with Acute Hepatitis of Unknown Etiology
- MMWR – Acute Hepatitis and Adenovirus Infection Among Children — Alabama, October 2021–February 2022
- ECDC – Epidemiological update: Hepatitis of unknown aetiology in children
- Joint ECDC-WHO Regional Office for Europe Hepatitis of Unknown Origin in Children Surveillance Bulletin
- UK – Increase in hepatitis (liver inflammation) cases in children under investigation
- AAP – Red Book Online Outbreaks: Hepatitis Cases Possibly Associated with Adenoviral Infection
- Updates on severe hepatitis of unknown etiology
- Severe acute hepatitis in children: investigate SARS-CoV-2 superantigens
- What’s sending kids to hospitals with hepatitis—coronavirus, adenovirus, or both?
- Pediatric Hepatitis Cases May Be Linked to Adenovirus, No Connection to COVID-19 Vaccination
- Unexplained hepatitis: severe liver inflammation among young children
- The CDC and WHO Have Reported an Unusual Cluster of Severe Pediatric Hepatitis Cases
- Organ Procurement and Transplant Network:SRTR 2019 Annual Data Report: Liver
Last Updated on May 23, 2022 by Vincent Iannelli, MD