The World Health Organization said one child died and more than a dozen who underwent liver transplants as a result of a mysterious outbreak of severe acute hepatitis in children in the United Kingdom, the United States and 10 other countries.
The World Health Organization said in a statement on Saturday that health authorities are trying to determine the source of the hepatitis infection that has infected at least 169 children, aged between one month and 16 years, as of April 21. Typical causes of viral hepatitis were excluded.
The UN agency was notified on 5 April of 10 cases among previously healthy children in central Scotland with jaundice, diarrhoea, vomiting and abdominal pain. Three days later, 74 cases were identified in the UK
As of April 21, the UK had 114 cases followed by 13 in Spain, 12 in Israel, nine in the US, and another 21 cases spread among Denmark, Ireland, the Netherlands, Italy, Norway, France, Romania and Belgium. Many have been infected with a strain of adenovirus, a family of viruses that cause a range of illnesses including the common cold.
“It is not yet clear whether there has been an increase in cases of hepatitis, or an increase in awareness of cases of hepatitis that are occurring at the rate expected but not detected,” the WHO said. “While adenovirus is a possible hypothesis, investigations into the causative agent are ongoing.”
The Geneva-based agency said 17 children, or about 10 percent of cases, required a liver transplant, and at least one death was reported. With more extensive research, she added, “it is very likely that more cases will be detected before the cause is confirmed and more specific control and prevention measures can be implemented.”
Symptoms include hepatitis, with marked elevation of liver enzymes, and jaundice, preceded by abdominal pain, diarrhea and vomiting. The World Health Organization said the common viruses that cause acute viral hepatitis – hepatitis A, B, C, D and E viruses – were not detected in any of the cases.
No international travel or links to other countries have revealed any evidence so far. Additional toxicology and microbiological testing are underway in the affected countries, which have also started enhanced surveillance activities.
Adenovirus is detected in more than 40 percent of cases. Of the virus samples that underwent molecular testing, 18 were identified as type F 41, the World Health Organization said. 19 cases were found to have SARS-CoV-2 and co-infection.
“Because of improved laboratory testing of adenovirus, this may represent the identification of a rare existing result occurring at previously undetected levels that are now being recognized due to increased testing,” the agency said.
More than 50 types of adenoviruses can cause infection in humans, according to the World Health Organization. Usually the cause of self-limited infectious infections, they mostly cause respiratory diseases. Depending on the type, they can also cause other diseases such as gastroenteritis, conjunctivitis and cystitis.
Type 41 adenoviruses, the strain implicated in outbreaks of liver disease, usually cause diarrhea, vomiting, and fever, often with respiratory symptoms. The World Health Organization said that although adenovirus has been investigated as a possible cause of the outbreak, it does not fully explain the severity of symptoms.
“While there have been reports of cases of hepatitis in immunocompromised children with adenovirus infection, type 41 adenovirus is not known to be a cause of hepatitis in healthy children,” she added.