CDC investigating 109 cases of severe hepatitis in children across 25 states and territories, including 5 deaths

The Centers for Disease Control and Prevention (CDC) headquarters in Atlanta, Georgia.

Tami Chappell | Reuters

The Centers for Disease Control and Prevention is investigating 109 cases of severe hepatitis, including five deaths, the public health agency said on Friday.

More than 90% of the children were hospitalized and 14% required liver transplants, according to the CDC. More than half of the kids had a confirmed adenovirus infection. However, public health officials said they don’t know yet if adenovirus is the actual cause.

Adenovirus is not a known cause of hepatitis in otherwise healthy children, though it has been linked to the illness in kids with weak immune systems.

The cases under investigation were found across 25 states and territories and occurred over the past seven months. The CDC has not documented a significant increase in hepatitis cases in kids or liver transplants, but that’s based on preliminary data and could change. However, the United Kingdom — which first alerted the world to the issue — has documented a significant increase, CDC officials said.

Covid-19 vaccination is not the cause of the illnesses, the CDC officials said. The children had a median age of two years, which means most of them were not eligible to receive the vaccine.

The CDC issued a nationwide health alert in late April about a cluster of severe hepatitis cases among nine children in Alabama. The World Health Organization is also closely monitoring cases of severe hepatitis in children globally.

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