The cause of a new type of hepatitis in children is found

cases of hepatitis, an inflammation of the liver, began appearing in children around the world. They were not caused by the hepatitis viruses that typically cause the illness. The World Health Organisation has reported more than 1,000 probable cases in 35 countries. Some children have required liver transplants and at least 22 have died. Researchers have been scrambling to find the cause.Two studies posted this week on medRxiv, a preprint server, propose an answer—co-infection with two common and usually innocuous viruses, probably helped by certain gene variations in the children who fell ill. -o-2 was ruled out as a culprit. One of the infections seems to be from human adenovirus, a common bug in children that causes stomach upsets but does not make them very ill. A cluster of the strange hepatitis cases appeared shortly after a spike in adenovirus infections, though it was unclear what role the virus might be playing, because it is often present in healthy children too.