The cases are in the pediatric population and come from 11 countries in the WHO European Region and 1 country in the WHO Region of the Americas.
The World Health Organization has reported 169 cases of acute hepatitis of unknown origin in kids ages 1 month to 16 years old.1 The reporting comes as of April 23.
One death has occurred, and 17 patients have required liver transplantation.
According to the WHO report, cases have been reported in the United Kingdom of Great Britain and Northern Ireland (the United Kingdom) (114), Spain (13), Israel (12), the US (9), Denmark (6), Ireland (<5), The Netherlands (4), Italy (4), Norway (2), France (2), Romania (1), and Belgium (1).
The Adenovirus has been detected in at least 74 cases, and WHO has said this could represent a rare outcome occurring at levels not previously detected that is now being recognized due to increased testing. The WHO said that although this virus is potential cause, investigators say is does not fully explain the severity of the ongoing cases. Specifically, infection with adenovirus type 4, which 18 patients have been identified as F type 41, does not typically present with this severity. Adenovirus 41 has not been shown to cause hepatitis in healthy children.
The WHO said it is closely monitoring the situation and working with the United Kingdom health authorities, other member states to understand the ongoing cases.
WHO recommends testing the blood (with initial anecdotal experience that whole blood is more sensitive than serum), serum, urine, stool, and respiratory samples, as well as liver biopsy samples should be undertaken, with further virus characterization including sequencing. Other infectious and non-infectious causes need to be thoroughly investigated the organization said.
Reference
1. World Health Organization (23 April 2022). Disease Outbreak News; Multi-Country – Acute, severe hepatitis of unknown origin in children. Available at:
