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.
Today the UKHSA is making is clear that none of the confirmed cases have received the vaccine.
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.
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.
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
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.
- In 2014, a rare - but known for decades - non-polio enterovirus EV-D68 sparked a nationwide outbreak of respiratory illness (see CDC HAN Advisory On EV-D68), and caused hundreds of cases of AFM (Acute Flaccid Myelitis).
- In 2015-2016, the Zika arbovirus sparked a tragic epidemic of congenital microcephaly in South America (see Lancet: Case-Control Study Confirms Association Between Zika and Microcephaly).
- And some scientists have suggested the mysterious neurological epidemic of Encephalitis Lethargica - which ran for about 10 years after the start of the 1918 pandemic - may have been caused by an enterovirus (see Evidence for an enterovirus as the cause of encephalitis lethargica).