At least 650 children across 33 countries have been diagnosed with mysterious, acute hepatitis infections since October 2021, roughly one-third of which have been detected in the United States, according to the World Health Organization.
In a statement issued Friday, WHO officials confirmed that 38 children have required a transplant due to unexplained liver inflammation, nine children have died and the lion’s share of the confirmed infections were diagnosed between April 5 and May 26.
An additional 99 cases are pending classification, the agency stated.
Data compiled by the agency - documenting all known cases between Oct. 1, 2021, and May 2 6- indicated that the United Kingdom has confirmed the highest number of cases at 222, followed closely by the United States with 216. Outbreaks in Japan, Spain and Italy round out the five most prolific to date with 31, 29 and 27 cases, respectively.
According to CBS News, 75% of the children who fell ill in Europe were under the age of five.
Of the 181 cases tested for adenovirus, typically associated with the common cold, 60% were positive, while 12% of the 188 children tested for COVID-19 were positive, the network reported.
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According to the WHO, cases have been atypically severe with this outbreak, and a “higher proportion develops acute liver failure compared with previous reports of acute hepatitis of unknown etiology in children.”
“While adenovirus is a plausible hypothesis as part of the pathogenesis mechanism, further investigations are ongoing for the causative agent; adenovirus infection (which generally causes mild self-limiting gastrointestinal or respiratory infections in young children) does not fully explain the more severe clinical picture observed with these cases,” the agency stated.
The cause of the outbreak remains under investigation, and the WHO classifies the global risk level as moderate, CBS News reported.
According to the U.S. Centers for Disease Control and Prevention, parents should remain vigilant for the following symptoms of acute hepatitis:
- fever
- fatigue
- loss of appetite
- nausea
- vomiting
- abdominal pain
- dark urine
- light-colored stools
- joint pain
- jaundice (yellowing of the skin)