Older cases of pediatric hepatitis have been reported, adding to the CDC's investigation of illness in otherwise healthy children.
More than 200 cases of hepatitis in children are under investigation, according to the US Centers for Disease Control and Prevention. The majority of these cases are retrospective cases, which means older cases are just now being reported as the CDC's investigation into liver damage of unknown cause continues. Five children have died from liver damage, but no additional deaths have been reported since February, according to a May 18 update by the CDC.
Although it's rare, children have developed hepatitis with an unknown cause, Dr. Jay Butler, CDC deputy director for infectious diseases, said during an early May media briefing. But the number of hepatitis cases in otherwise healthy children is what prompted the CDC to start investigating and pinpoint a link reported in some European countries as well as the US.
A preliminary analysis in the US didn't find a significant increase in pediatric hepatitis cases or liver transplants, Butler noted earlier this month. But other countries with universal medical records and better health care tracing have reported an increase in hepatitis cases in children under age 5, Healthline reported.
Adenovirus has been detected in about half of the children, according to the CDC, and continues to be "a strong lead." The CDC is specifically looking at adenovirus type 41, which usually causes gastrointestinal symptoms in children.
"It's important to note that this is an evolving situation," Butler said earlier this month. "We're casting a wide net to help broaden our understanding." The CDC is conducting a review of these reports, which date back to 2021, he said.
Adenoviruses are common viruses that can cause coldlike symptoms, bronchitis, diarrhea, pinkeye and other problems. Hepatitis is an inflammation of the liver that can lead to liver failure in some cases. The liver's role is to filter blood, help fight infections and other important functions.
Because adenoviruses aren't known to cause hepatitis in otherwise healthy children who aren't immunocompromised, the CDC is asking public health authorities to report all hepatitis cases with unknown causes to their local and state health departments.
The reports of hepatitis in children are still rare occurrences overall, but health officials are investigating the cases because it's unusual for otherwise healthy children to develop severe hepatitis. The CDC is investigating reports in children under age 10 with signs of hepatitis.
The CDC is investigating over 200 pediatric reports of hepatitis in the US across 38 states and territories over the past several months. Over 90% of children were hospitalized, and some needed liver transplants, Butler said at the media briefing. The United Kingdom is investigating similar cases in children.
The original CDC alert was based on a report of nine children ranging ages 1 to 6 years old who were treated at a hospital in Alabama for hepatitis. Some tested positive for adenovirus type 41. Adenovirus 41 is more typical in immunocompromised patients, and isn't known to cause hepatitis in otherwise healthy children, Butler said. He added that the nine initial cases haven't been linked to COVID-19 infection, and none of the sick children had been vaccinated. Most weren't even eligible for a COVID-19 vaccine, which is only available to kids age 5 and up.
The CDC said it's asking parents and caregivers to be aware of the symptoms of hepatitis and contact their health care provider with any concerns.
Some symptoms of hepatitis, according to the American Academy of Pediatrics, include:
There are vaccines for hepatitis A and hepatitis B.
Hepatitis can have different causes, including drug use, alcohol use and even certain medical conditions. It can also be caused by a virus; the most common types of viral hepatitis in the US are hepatitis A, B and C. The CDC has ruled out all three of these types of hepatitis in the pediatric cases it announced.
Some cases of hepatitis are acute (they don't last more than six months) while others are chronic (lasting more than six months). Hepatitis C, which is spread through blood contact, causes chronic liver infection in 75% to 85% of patients, according to the Cleveland Clinic.