The World Health Organization (WHO) on Tuesday reported nearly 230 probable cases of hepatitis of unknown origin in children reported in 20 countries.
“More than 50 other cases are under investigation,” said WHO spokesperson Tarik Jasarevic during a press briefing in Geneva.
Cases of these severe liver inflammations whose origin remains to be determined have been reported by four of the six WHO regions, he said.
The majority of cases have been reported in Europe, first in the United Kingdom.
The first cases of severe acute hepatitis of unknown etiology in children under 10 were detected in early April in central Scotland. By April 8, 74 cases had been identified in the UK.
This hepatitis mainly affects children under the age of 10, and is manifested by symptoms such as jaundice, diarrhea, vomiting and abdominal pain. Some cases required liver transplantation. At least one child has died.
The usual viruses that cause acute viral hepatitis (A to E) were not detected in any of the cases, according to the European Center for Disease Control and Prevention (ECDC) and WHO.
An analysis of these mysterious cases of hepatitis in the United States led the American health authorities to favor the track of an adenovirus last week without however establishing it as a definitive cause.
Commonplace, adenoviruses are generally rather known to cause respiratory symptoms, conjunctivitis or even digestive disorders.
Transmission occurs by the faecal-oral or respiratory route, with epidemic peaks often in winter and spring, and more often in communities (nurseries, schools, etc.). The majority of humans are infected before they are 5 years old.