NINE children affected by a mysterious hepatitis (inflammation of the liver) all tested positive for a common pathogen called adenovirus 41 in Alabama, showed a study by the US Centres for Disease Control and Prevention (CDC) yesterday.

The children, who ranged in age from about 1 to 6 years old and were all previously healthy, are among 170 cases across 11 countries in recent weeks, according to the World Health Organisation.

Another state, Wisconsin, is investigating a death.

The CDC’s new paper is specifically about the cluster in Alabama, even as investigations continue nationwide.

“At this time, we believe adenovirus may be the cause for these reported cases, but other potential environmental and situational factors are still being investigated,” it said in a statement that accompanied the study.

Adenovirus 41 is known to cause gastroenteritis in children, but “not usually known as a cause of hepatitis in otherwise healthy children”, it added.

However, an investigation ruled out other common exposures, including Covid-19; hepatitis viruses A, B, and C (the most common causes of hepatitis in the US); autoimmune hepatitis; and, Wilson disease.

The nine cases occurred between October 2021 and February 2022. Three experienced acute liver failure, two of whom required liver transplants.

“All patients have recovered or are recovering, including the two transplant recipients,” said the paper.

Six tested positive for Epstein-Barr Virus but did not have antibodies, which implies an earlier infection, not active.

Before hospitalisation, most of the children experienced vomiting and diarrhoea, while some experienced upper respiratory symptoms. During hospitalisation, most had yellowing eyes and skin (jaundice), and enlarged livers.

The CDC last week issued a health alert to notify doctors and public health authorities to be on the lookout for similar cases.

Wisconsin is investigating four cases, including two children who had severe outcomes—one who needed a liver transplant and one fatality. Illinois and other places have also reported cases.

CDC recommends children stay up to date on their vaccinations, and parents and caregivers practice preventive actions such as hand hygiene, covering coughs and sneezes, avoiding sick people and avoiding touching the eyes, nose or mouth.

Adenoviruses are commonly spread by close personal contact, respiratory droplets and surfaces. There are more than 50 types of the virus, which most commonly cause the cold, but also many other diseases. – AFP, April 30, 2022.