The first case was reported on April 25, followed by the second on April 28. Four more possible cases were reported on May 6, the ministry said in a statement (pdf). The patients are all under the age of 16.
One of them tested positive for COVID-19, and another Adenovirus Type 1, the ministry said according to The Japan Times, without mentioning whether these were two separate people or one person who caught both viruses.
It stated that the seven recorded cases comprised children admitted to hospitals between October, 1. 2021 and May, 6. 2022, with some having already been discharged. None of the patients received a liver transplant.
The World Health Organization (WHO) told news outlets on May 3 that there were at least 228 probable cases of hepatitis worldwide in at least 20 countries, including Denmark, the United States, the United Kingdom, Italy, and France.
WHO stated on April 23 that the cases involved children aged one month to 16 years old, many of whom developed gastrointestinal symptoms, including abdominal pain, diarrhea, and vomiting preceding presentation with severe hepatitis and jaundice (yellowing skin and eyes).
“The common viruses that cause acute viral hepatitis (hepatitis viruses A, B, C, D, and E) have not been detected in any of these cases. International travel or links to other countries based on the currently available information have not been identified as factors,” it said.
In Indonesia, a mysterious form of hepatitis has been linked to the deaths of three children ages two, eight, and 11, The Jakarta Post reported on May 3. The Health Ministry said the children developed diarrhea and jaundice, adding that the case was still under investigation.
The U.S. Centers for Disease Control and Prevention (CDC) said Friday that it was investigating more than 10 cases of a mysterious form of hepatitis in children, saying that five have died so far.
Dr. Jay Butler, the CDC’s deputy director of infectious diseases, said during a briefing said the agency is investigating 109 cases of acute hepatitis in 24 U.S. states and Puerto Rico. The cause of the outbreak is not yet clear, he stressed, adding that about half of the children had adenovirus infections.
The UK Health Security Agency reported that (pdf) the country’s case count had risen to 163, dating back to early January, adding that 11 children have received liver transplants so far. UK officials ruled out the COVID-19 vaccine as a potential cause.
“There are fewer than five older case-patients recorded as having had a COVID-19 vaccination prior to hepatitis onset,” the report said, adding that most of the impacted children are too young to receive the shot. “There is no evidence of a link between COVID-19 vaccination and the acute hepatic syndrome.”
Jack Phillips contributed to this report.