Health officials in several countries are investigating mysterious cases of severe liver disease in children, and they think it may be related to a kind of virus usually associated with colds.

The U.K. has been investigating at least 74 cases in which children came down with hepatitis, or liver inflammation, the World Health Organization said Friday. Three similar cases in Spain and a few in Ireland are being investigated, the WHO said.

Meanwhile, U.S. health officials say they are looking into nine similar cases. All were in Alabama, but officials say they are looking to see if there are more elsewhere.