On Tuesday, the World Health Organization reported that 348 likely instances of hepatitis of unknown cause had been detected.

20 countries have reported such cases, while additional 70 such cases from 13 different countries were awaiting classification and confirmation after completion of tests. Only six countries have recorded more than five cases, with the United Kingdom reporting more than 160. The severity of the disease resulted in liver transplants in some cases. Several patients complained of stomach pain, diarrhea, and vomiting.

According to Philippa Easterbrook of the WHO′s global hepatitis programme, the genetics of the children affected, their immune response, viruses, and further epidemiological studies are being carried out to establish the etiology of hepatitis mystery. Experts think that the involvement of Adenovirus might be the primary cause however, the role of Covid was also investigated. She stated that testing in the last week indicated that roughly 70% of the cases tested positive for adenovirus, with sub-type 41, which is usually associated with gastroenteritis, being the most common sub-type. Around 18% of cases actively tested positive for Covid-19, according to testing. Serological testing for previous Covid exposure and infections was also carried out.

Microscopic examinations of liver samples and biopsies have ruled out adenovirus-induced liver inflammation. The WHO stated that common viruses that cause acute viral hepatitis (hepatitis viruses A, B, C, D, and E) were not found in any of the first 169 cases. So, the WHO has declared it an epidemic of severe liver inflammations known as acute hepatitis of unknown cause affecting young children.