Earlier this month was reported that 11 children aged between one and five had been admitted to hospitals in Lanarkshire, Glasgow, Tayside and Fife.

Mid-April the WHO issued a note "Acute hepatitis of unknown aetiology – the United Kingdom of Great Britain and Northern Ireland"

This now has been found in four European countries and the US.

The CDC has now issued a notice:  

 

The first U.S. cases were identified in October 2021 at a children’s hospital in Alabama that admitted five children with significant liver injury (including some with acute liver failure) without known cause, who also tested positive for adenovirus. Hepatitis A, hepatitis B, and hepatitis C viruses were ruled out.

 

Upon investigation, a review of hospital records identified four additional cases, all of whom had liver injury and adenovirus infection; laboratory tests identified that some of these children had adenovirus type 41, which more commonly causes pediatric acute gastroenteritis. No known epidemiological link or common exposures were found among these children. A statewide alert to elicit additional cases on February 1, 2022, has not yielded any further reports.

 

CDC is also aware of an increase in cases of pediatric hepatitis without a known cause recently reported in Europeexternal icon, and has been in contact with our European counterparts to understand what they are learning.  Adenovirus has been confirmed in several of the European cases, but not all.

 

Symptoms of hepatitis, or inflammation of the liver, include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, light-colored stools, joint pain, and jaundice and can be caused by viruses. Adenoviruses spread from person-to-person and most commonly cause respiratory illness, but depending on the type, can also cause other illnesses such as gastroenteritis (inflammation of the stomach or intestines), conjunctivitis (pink eye), and cystitis (bladder infection). Adenovirus type 41 typically presents as diarrhea, vomiting and fever, often accompanied by respiratory symptoms. While there have been case reports of hepatitis in immunocompromised children with adenovirus infection, adenovirus type 41 is not known to be a cause of hepatitis in otherwise healthy children.

 

CDC is working with state health departments to see if there are additional U.S. cases, and what may be causing these cases. At this time, we believe adenovirus may be the cause for these reported cases, but investigators are still learning more – including ruling out other possible causes and identifying other possible contributing factors. So far, other common causes of viral hepatitis, such as Hepatitis A, B, and C have been ruled out. CDC and state public health officials will continue to work together in close collaboration with clinicians to identify and detect unusual patterns or clusters of illness to prevent further disease.

 

CDC is asking physicians to consider adenovirus testing for pediatric patients with hepatitis of unknown etiology, and to report any possible cases of hepatitis of unknown origin to CDC and state public health authorities.