The World Health Organization (WHO) has published an update reporting on at least 169 cases of minors affected by acute hepatitis of unknown origin in 12 countries, most of them located in Europe. These are children between one month and 16 years old; in 17 cases (approximately 10% of the total) a liver transplantation was required, and there was one reported death. The WHO is investigating the origin of the outbreak and acknowledges that “it is not yet clear whether there has been an increase in hepatitis cases or an increase in awareness of hepatitis cases that occur at the expected rate but go undetected.”
The WHO has admitted that one of the hypotheses focuses on the origin being due to an adenovirus (which has been detected in at least 74 cases). But the statement adds that “while adenovirus is currently one hypothesis as the underlying cause, it does not fully explain the severity of the clinical picture.” Adenoviruses are very common pathogens that almost always cause mild or very mild respiratory or gastrointestinal symptoms.
The United Kingdom was the first country to notify the increase in cases of hepatitis of unknown origin on April 15 and health authorities there have already reported 114 patients. The second country that accumulates the most cases so far, according to information released on Saturday by the WHO, is Spain with 13, followed by Israel (12), the United States (9), Denmark (6) and Ireland (5).
In identified cases it is an acute hepatitis (inflammation of the liver) with markedly elevated liver enzymes, explains the WHO. Many cases reported gastrointestinal symptoms including abdominal pain, diarrhea and vomiting that preceded severe acute hepatitis and elevated liver enzyme levels. “Most of the cases did not have a fever,” explains the WHO. The origin is unknown because “the common viruses that cause acute viral hepatitis” have not been detected in any of the cases.
All eyes are turning to adenovirus because the UK, where most cases have been reported so far, has recently seen a significant increase in adenovirus infections in children. The health authorities of the Netherlands have reported something similar, says the WHO. But this agency does not rule out that this increase in the detection of adenoviruses may be due to an improvement in laboratory tests to detect this infection.
The first investigations pointed to the possibility of this being a side effect of Covid – the coronavirus was identified in several hepatitis cases. An adenovirus, an infection of toxic origin or an entirely unknown virus were not ruled out either.