Tuesday, April 12, 2022

UKHSA Update On Hepatitis Outbreak In Children

 #16,690

Six days ago the UKHSA announced an outbreak of acute hepatitis of unknown etiology in scores of children in England and Scotland, some of whom have required liver transplants.  On Saturday, we followed up with an Update/Guidance On the Hepatitis Outbreak.

As I mentioned in my last update, some on social media are suggesting (without evidence) the COVID vaccine is to blame for this surge - despite most of these cases have occurred in children under the age of 5 - who are too young to receive the vaccine.

Today the UKHSA is making is clear that none of the confirmed cases have received the vaccine

While the cause remains unknown, the UKHSA is exploring the possibility that an adenovirus infection might be behind these hepatitis cases, although they haven't ruled out other viruses, including COVID. 

Adenoviruses have been linked to acute hepatitis, although it is most commonly seen in immunocompromised patients.  A recent, notable exception was described in Adenovirus Hepatitis in Immunocompetent Adults

Adenoviruses - of which there are dozens - are a common cause of (generally mild) respiratory illnesses in both adults and children. Serious illness can sometimes occur however, particularly in immunocompromised or medically fragile individuals.

We've looked at severe adenovirus outbreaks in the past, including a multi-state outbreak of virulent serotype Ad14 15 years ago (see 2007 MMWR Acute Respiratory Disease Associated with Adenovirus Serotype 14 --- Four States, 2006—2007and in 2012, China: Hebei Outbreak Identified As Adenovirus 55.

In 2016, we looked at a report in the EID Journal: Human Adenovirus Associated with Severe Respiratory Infection, Oregon, USA, 2013–2014, that described a relatively large outbreak in the Pacific Northwest.
During October 2013–July 2014, Oregon health authorities identified 198 persons with respiratory symptoms and an HAdV-positive respiratory tract specimen. Among 136 (69%) hospitalized persons, 31% were admitted to the intensive care unit and 18% required mechanical ventilation; 5 patients died. 

For now, the cause of this hepatitis outbreak remains unknown.  Today's update from the UKHSA follows. I'll have a brief postscript after the break. 

Increase in hepatitis (liver inflammation) cases in children under investigation

The UK Health Security Agency (UKHSA) has recently detected higher than usual rates of liver inflammation (hepatitis) in children. Similar cases are being assessed in Scotland.

From:UK Health Security Agency  Last updated 12 April 2022 — See all updates

Latest

Public health doctors and scientists at the UK’s public health agencies are continuing to investigate 74 cases of hepatitis (liver inflammation) in children since January 2022, where the usual viruses that cause infectious hepatitis (hepatitis A to E) have not been detected.

Of the confirmed cases, 49 are in England, 13 are in Scotland and the remainder are in Wales and Northern Ireland.

One of a number of potential causes under investigation is that a group of viruses called adenoviruses may be causing the illnesses. However, other possible causes are also being actively investigated, including coronavirus (COVID-19), other infections or environmental causes.

There is no link to the COVID-19 vaccine. None of the currently confirmed cases in the UK has been vaccinated.

Adenoviruses are a family of common viruses that usually cause a range of mild illnesses and most people recover without complications. They can cause a range of symptoms, including colds, vomiting and diarrhoea. While they don’t typically cause hepatitis, it is a known rare complication of the virus.

Adenoviruses are commonly passed from person to person and by touching contaminated surfaces, as well as through the respiratory route.

The most effective way to minimise the spread of adenoviruses is to practice good hand and respiratory hygiene and supervise thorough handwashing in younger children.

Dr Meera Chand, Director of Clinical and Emerging Infections at UKHSA, said:
We are working swiftly with the NHS and public health colleagues in Scotland, Wales and Northern Ireland to investigate a wide range of possible factors which may be causing children to be admitted to hospital with liver inflammation known as hepatitis.
One of the possible causes that we are investigating is that this is linked to adenovirus infection. However, we are thoroughly investigating other potential causes.
Normal hygiene measures such as good handwashing – including supervising children – and respiratory hygiene, help to reduce the spread of many of the infections that we are investigating.
We are also calling on parents and guardians, to be alert to the signs of hepatitis – including jaundice – and to contact a healthcare professional if they are concerned.
UKHSA, working with partners, will continue to make the public aware of findings throughout the course of the investigation.

It isn't clear why the UKHSA is focusing on an adenovirus infection, but presumably something in their epidemiological investigation has raised red flags in that direction.  

While it might be unusual for an adenovirus to spark an outbreak of hepatitis in (presumably) immunocompetent children, it wouldn't be the first time that an old virus learned new tricks. 

Unusual, yes.  But with viruses, we never like to say `never'.