An analysis of mysterious cases of hepatitis in very young children in the United States led the American health authorities to favor Friday the track of an adenovirus to explain these severe inflammations of the liver, without however establishing it as a definitive cause.
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Fairly banal viruses, adenoviruses are generally rather known to cause respiratory symptoms, conjunctivitis or even digestive disorders.
The United States is far from being the only country affected by this phenomenon of unexplained hepatitis: dozens of cases have been identified all over Europe, raising fears of a new epidemic.
“At this time we believe an adenovirus may be the cause of these cases, but other environmental factors are still being investigated,” wrote the Centers for Disease Control and Prevention (CDC), the lead federal agency. public health in the country.
More specifically, the CDC points the finger at the so-called “type 41” adenovirus, hitherto best known for causing severe gastroenteritis.
Adenoviruses are well identified as causes of hepatitis, but so far only in immunocompromised children (ie whose immune system is weakened).
A total of nine cases identified in Alabama between October 2021 and February 2022 have been studied in detail.
The children were approximately one to six years old, and were all otherwise healthy.
Most children experienced vomiting and diarrhea, and some respiratory symptoms.
Two children had to undergo a liver transplant. All are currently cured or in remission.
The nine little patients were found to be carriers of adenovirus. Five cases could be analyzed in the laboratory, and type 41 adenovirus was then detected.
The CDC has ruled out several other causes, including COVID-19 infection, and hepatitis A, B, and C viruses.
Six of the nine patients also tested positive for the Epstein-Barr virus, but they “did not have antibodies, which implies a past infection, no longer active”, wrote the American agency.
She assured to be in close contact with the European health authorities.
Cases are also being investigated in other US states. Wisconsin health authorities said this week they are reviewing four possible cases in children, including one death.
Last week, the CDC issued a health alert for physicians to notify authorities of any suspected cases of hepatitis of unknown origin.