Authorities are scrambling to investigate the potential cause of an unusually high number of acute hepatitis cases in children around the world and the UK, which some say may be caused by COVID-19 lockdowns which have weakened immunity.
In a statement on Tuesday, the UK Health Security Agency (UKHSA) said it working with the National Health Service (NHS) and the public health agencies of England, Wales, Scotland, and Northern Ireland, to investigate the potential cause of an unusually high number of acute hepatitis cases being seen in children in the past few weeks.
In the UK, as of 20 April 2022, there have been 111 cases of “hepatitis of unknown origin” identified in children aged under 16 years old, since Jan. 1. Of these cases, 10 children have received a liver transplant. No UK cases have died. A small number of children over the age of 10 are being investigated.
The usual viruses that cause infectious hepatitis (hepatitis A to E) have not been detected.
While still under investigation, officials believe that one potential cause is a group of viruses called adenoviruses that may be causing the illnesses. Adenovirus has been detected in at least 74 cases.
“At the time of publication, the leading hypotheses centre around adenovirus—either a new variant with a distinct clinical syndrome or a routinely circulating variant that is more severely impacting younger children who are immunologically naïve. The latter scenario may be the result of restricted social mixing during the COVID-19 pandemic,” wrote Eurosurveillance.
Authorities said that there is no link to the COVID-19 vaccine. None of the currently confirmed cases in the UK has been vaccinated.
“The point is what we’ve done with lockdowns is that we’ve massively disrupted the way that we interact with each other and consequently we’ve interrupted microorganisms and the way we spread them to one another,” she said.
“Adenoviruses have been linked previously to hepatitis, but nearly all cases have been in the severely immunocompromised,” it added.
“As early as June 2020, warnings were issued during the lockdowns that restricting mixing of children, and the consequent reduced exposure to the normal range of viruses, could have deleterious effects, creating an ‘immune debt’ which would have to be ‘repaid’ eventually,” added HART.