Last month we learned of mysterious unexplained hepatitis cases popping up in children around the world, including in the United States:

Bad news: It's getting worse and there's still no explanation for it.

The U.S. Centers for Disease Control and Prevention is investigating mysterious cases of hepatitis among young children.

In 109 cases since October being investigated, five children died and several more needed a liver transplant. About half of the children had confirmed cases of an adenovirus, a common class of viruses that can cause congestion and flulike symptoms.

Doctors don't yet know the cause of these cases but are researching whether there may be a link between hepatitis and adenovirus, as well as other potential contributing factors.

The U.S. Centers for Disease Control and Prevention is investigating mysterious cases of hepatitis among young children.

In 109 cases since October being investigated, five children died and several more needed a liver transplant. About half of the children had confirmed cases of an adenovirus, a common class of viruses that can cause congestion and flulike symptoms.

Doctors don't yet know the cause of these cases but are researching whether there may be a link between hepatitis and adenovirus, as well as other potential contributing factors.

The nature of the hepatitis infections is particularly troubling:

Health experts say a majority of them were infected by what's known as an adenovirus which is a fairly common virus. But this particular form of the virus is different.

"More infecting the kids, more directly to the G.I. tract but rarely in the past go to the liver, and this one goes to the liver. That's what really concerns us," said Dr. Naoky Tsai, a liver specialist.

They gotta solve this one. Bring in House, Doogie Howser, I don't care—somebody needs to figure this out and quick.

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