Ilias Mosialos: What do we know about cases of hepatitis of unknown cause in children?

The correlations with the vaccine for the coronavirus of increased cases of hepatitis – cause unknown at this time– in children under 10 years of age, according to a Facebook post by Professor of Health Policy, Elias Mosialos of the School of Economics & Political Science and Imperial College London.

An increase in such cases has been noted in recent months in the United Kingdom, the United States, Spain, Denmark, Ireland, and the Netherlands. In the United Kingdom, 74 cases have been recorded since January 2022, of which 49 were in England, 13 in Scotland, and 12 between Wales and Northern Ireland. As the Greek scientist points out, «the numbers are obviously small, but to understand the difference, a typical number of cases of hepatitis of unknown cause across Scotland is less than 4 per year. First of all, let's say that none of the currently confirmed cases in the UK have been vaccinated for coronavirus.» So there is no question of a link between hepatitis and Covid-19 vaccines.

On April 15, the World Health Organization (WHO) issued a statement saying that on April 5, the WHO was informed of 10 cases. Severe acute hepatitis of unknown cause in children under 10 years of age in Scotland. By April 8, 74 cases had been identified in the United Kingdom. Hepatitis viruses (A, B, C, E, and D, as applicable) have been ruled out following laboratory testing, and further investigations are ongoing to understand the cause of these cases.

Health officials in Alabama, USA, also issued a statement reporting nine cases of hepatitis dating back to November 2020. None of the children had underlying health problems, the statement said, but two of the nine required liver transplants.

One of the possible causes under investigation is that a group of viruses called adenoviruses may cause the disease. However, other possible causes are also being thoroughly investigated. Adenoviruses are a family of common viruses that usually cause a range of mild symptoms, and most people recover without complications. They can cause colds, vomiting, and diarrhea. They do not usually affect the liver (to cause hepatitis), but this has been reported as a known but rare complication of the virus.

Adenoviruses are usually transmitted from person to person, from contaminated surfaces, and through the respiratory tract. Therefore, the most effective way to minimize the spread of adenoviruses is through standard hygiene measures, such as washing your hands thoroughly and being careful when coughing or sneezing, or when someone else coughs or sneezes near you. Younger children also need to be taught and supervised during thorough hand washing.

The World Health Organization guidelines recommend caution and priority in determining the cause of cases so that further clinical actions and public health measures can be coordinated. Any epidemiological links between cases may provide clues to the cause of the disease. The temporal and geographical information of cases, as well as their contacts, should also be examined.

While some cases tested positive for SARS-CoV-2 and/or adenovirus, genetic characterization of the viruses should be performed to determine any possible associations between cases. Health authorities should identify, investigate, and report possible cases where symptoms are consistent with hepatitis.

«At the same time,» concludes Mr. Mosialos, «parents should be alert to unusual reactions, including jaundice. If they notice any strange symptoms, it is advisable to contact their children's pediatrician.».