The World Health Organization (WHO) detected at least 169 cases of acute hepatitis of unknown origin in children aged 1 month to 16 years, according to a statement based on the latest data. At least one child has died and 17 have required a liver transplant.
“It is not yet clear if there has been an increase in hepatitis cases, or an increase in awareness of hepatitis cases that occur at the expected rate but go undetected,” the statement says.
Hepatitis that causes liver inflammation in the human organism has a variety of triggers. They include four hepatitis viruses (A, B, C, or E), other viruses, as well as bacteria, alcohol abuse, metabolic or autoimmune diseases.
The severe form of hepatitis among children is extremely rare, especially in cases when doctors fail to determine the trigger. Such cases were first reported in Scotland last month, when 12 children at once were diagnosed with hepatitis. Later other countries, including Spain, Ireland, Denmark, the Netherlands and the USA (Alabama), reported similar cases of children with acute hepatitis symptoms.
The cause of the inflammation remains unknown. According to a report by Scottish doctors, published in Eurosurveillance, none of the patients had hepatitis viruses, as well as many other viruses that can affect the liver, such as enteroviruses and some herpesviruses. Almost all of the children were healthy; none of the patients had immunodeficiency. Moreover, none of them had been vaccinated against COVID-19, so the hepatitis wasn’t attributed to a side effect of the vaccine.
Doctors suspect other viruses to be the cause of the disease as in some patients, antibodies to SARS-CoV-2 were detected, which have been already said to trigger diabetes in children, which means it could hypothetically cause hepatitis as well. In addition, doctors drew attention to adenovirus, which has been also found in several children. Normally, it rarely causes inflammation of the liver, but the researchers suggested that during the years of the pandemic, children spent a lot of time in isolation and did not have time to develop immunity to it, which is why adenovirus affected them in such a severe form.
“While adenovirus is a possible hypothesis, investigations are ongoing for the causative agent,” the WHO said.
According to the organization, adenovirus was detected in at least 74 patients, and adenovirus group F (type 41) was found in 18 people during molecular testing. The WHO advised member countries to investigate and report each case, but didn’t recommend any restrictions.