April 21, 2022, at least 169 cases of acute hepatitis of unknown etiology have been reported from 11 countries in the WHO Europe Region and one country in the WHO Americas Region. Cases have been reported in the United Kingdom of Great Britain and Northern Ireland (United Kingdom) (114), Spain (13), Israel (12), United States (9), Denmark (6), Ireland (< 5), Netherlands (4), Italy (4), Norway (2), France (2), Romania (1), and Belgium (1).

Cases include infants and children aged 1 month to 16 years. Seventeen children (about 10%) required liver transplantation; at least one death has been reported. The clinical syndrome that appears is acute hepatitis (liver inflammation) with marked elevation of liver enzymes. Many cases report gastrointestinal symptoms including abdominal pain, diarrhea and vomiting prior to the appearance of acute severe hepatitis, and elevated levels of liver enzymes (aspartate transaminase (AST) or alanine aminotransaminase (ALT) greater than 500 IU/L) and jaundice. Most cases do not have a fever. The common viruses that cause acute viral hepatitis (hepatitis A, B, C, D and E viruses) have not been detected in these cases.

Adenovirus has been detected in at least 74 cases, and of the number of cases from molecular testing information, 18 have been identified as type F 41. SARS-CoV-2 was identified in 20 cases tested. Subsequently, 19 were detected with SARS-CoV-2 and adenovirus coinfection. While adenovirus is currently one of the hypotheses as the underlying cause, this does not fully explain the severity of the presenting clinical picture. Adenovirus type 41 infection, the type of adenovirus involved, has not previously been associated with such a clinical presentation.

Further investigation is needed to identify additional cases, both in the currently affected countries and elsewhere. The priority is to determine the causes of these cases with the aim of further improving control and prevention measures. Common preventive measures for adenovirus and other common infections involve regular hand washing and respiratory hygiene.

WHO recommends that blood testing (with initial anecdotal experience that whole blood is more sensitive than serum), serum, urine, stool, and respiratory samples, and liver biopsy samples (where available) should be performed, with further virus characterization including sequencing. Other infectious and non-infectious causes need to be thoroughly investigated.

WHO does not recommend restrictions on travel and/or trade with the United Kingdom, or any other country where cases are identified, based on currently available information.

 

Source :

https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON376