The mysterious severe hepatitis outbreak afflicting children worldwide has now hit 25 U.S. states, with reports of possible cases coming in from two dozen others -- New York included -- since the CDC confirmed nine in Alabama last month, the federal health agency said in a conference call update on Friday.
Neither New Jersey nor Connecticut is included in the list of states that have submitted cases to the CDC for investigation. It wasn't clear from the CDC's update how many potential case reports are linked to the Empire State either.
Altogether, the CDC said it is now investigating 109 pediatric patients for possible infection linked to the outbreak. It initially sent out its advisory on the nine Alabama cases of hepatitis, or inflammation of the liver, 15 days ago. Much is still unknown.
Of the 109 potential reported U.S. cases, which the CDC says it is working "diligently" to evaluate, five children have died. More than 90% of those patients were hospitalized, 14% had liver transplants and more than half had confirmed adenovirus infections, the CDC said. All were sick in the last seven months.
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The kids in Alabama all were previously healthy, came from different parts of the state and all were hospitalized with significant liver injuries with no known cause. Some had acute liver failure. All tested positive for the typically mild adenovirus.
Health officials stressed, though, that they don't know if an adenovirus is the cause.
Most of the kids, who were diagnosed between October 2021 and February 2022, have recovered fully or are expected to recover fully, the CDC said. Asked about potential links to COVID-19, the agency said none of the Alabama kids had previously been clinically diagnosed though noted some may have still had it.
None were vaccinated for COVID-19 either, but the median age of the nine patients in Alabama was 2, which is below the eligible age for COVID vaccinations. Outside Alabama, the CDC says it is not aware of a potential connection to COVID infection.
Ultimately, the CDC described the hepatitis outbreak as an "evolving situation" and said it was casting a wide net to broaden its understanding. That includes working with public health officials across the globe, including in the UK, which has seen the most cases of the severe liver disease in kids linked to this investigation.
The agency is also looking into whether other factors like environmental exposure, medication or different infections could be contributors.
Concerned parents should be aware of the symptoms of liver inflammation, which include fever, fatigue, diarrhea, abdominal pain and other cold-like issues. Learn more about the CDC's investigation and what families can do to protect themselves.