Mystery liver illness cases in kids swell to more than 900 worldwide, WHO says

More than 920 probable cases of severe acute hepatitis of unknown origin in children have been reported across 22 countries, the World Health Organization confirmed Friday.

>> Read more trending news

That figure represents a more than three-fold increase since May, according to Reuters.

To date, half the probable cases have been detected in the WHO’s European region, including 267 cases in the United Kingdom, while roughly one-third of the cases have been detected in the United States, the agency confirmed.

The latest WHO data includes information reported as of Wednesday but excluded data from four countries with reported cases yet to be classified, Reuters reported.

The outbreak of unexplained liver inflammation among children was first reported in the U.K. in April but has since spread to nearly two dozen other countries.

Closer to home, 296 probable acute pediatric hepatitis cases had been identified in the United States by Friday, according to the U.S. Centers for Disease Control and Prevention.

While the figure sounds high, the 2022 U.S. cases have not exceeded the expected yearly number of severe pediatric hepatitis cases, NBC News reported, noting that the majority of U.S. cases were actually identified in retrospect, some as far back as October 2021.

Per the CDC:

  • Most U.S. cases were in children under 5 years old, and the average age was 2.
  • Nearly 90% of ill U.S. children required hospitalization.
  • 6% of ill U.S. children needed a liver transplant.
  • 11 ill U.S. children died.
  • Just under half of 224 U.S. pediatric patients were tested for an adenovirus infection, and 45% tested positive.

Globally, 18 children have died from the unexplained illness and 45 have required liver transplants, according to the WHO.