Canadian health officials are investigating cases of severe acute hepatitis of “unknown origin” found in children across the country.

The Public Health Agency of Canada (PHAC) told Global News on Wednesday it is aware of reports of this illness as other regions in the world report cases of liver disease in kids with an unknown cause.

“These are being investigated further to determine if they are related to cases in the United Kingdom and the United States,” PHAC said. “As the investigation evolves, we will keep the public updated accordingly.”

Here’s what we know so far.

So far, 190 children worldwide have developed sudden liver disease for reasons unknown. At least one child died and several others needed to have liver transplants, the WHO said.

Otherwise healthy children are developing hepatitis, or liver inflammation often caused by viruses. Children impacted so far range in age from one month to 16 years.

Most cases have occurred in Europe. The first U.K. cases were recorded in January, while the U.S. detected its first cases in October in Alabama. The Centers for Disease Control and Prevention made that announcement last week.