CDC scrambling to understand cause of over 100 hepatitis cases in kids

The Centers for Disease Control and Prevention said it is casting a “broad net” to understand why the U.S. and other countries are seeing a cluster of mysterious hepatitis cases in children that have resulted in five American deaths since October.

Officials said they are investigating 109 U.S. cases that have appeared in half the country since Alabama officials reported an initial cluster of nine cases in children 10 or younger in the fall. About 90% of the patients have been hospitalized and 14% required a liver transplant.

The cases don’t seem to be related to the strains of hepatitis — inflammation of the liver — that are typically found, giving the situation an air of mystery. But scientists believe an adenovirus might be involved because about half of the children tested positive for the pathogen.

CDC officials said they are scrambling to check for environmental or other factors that might be to blame. For instance, the U.K. Health Security Agency said it is investigating whether exposure to household dogs had something to do with the cases.

“We really are casting a broad net and keeping an open mind,” said Jay Butler, the CDC’s deputy director for infectious diseases.

The World Health Organization this week said more than 200 cases have been reported from 20 countries.

In the U.S., cases have been recorded in Alabama, Arizona, California, Colorado, Delaware, Florida, Georgia, Idaho, Illinois, Indiana, Louisiana, Michigan, Minnesota, Missouri, North Carolina, North Dakota, Nebraska, New York, Ohio, Pennsylvania, Puerto Rico, Tennessee, Texas, Washington state and Wisconsin.

Cincinnati Children’s Hospital in Ohio said Wednesday they’ve seen seven patients, all of whom were previously healthy kids ages 18 months to 10 years, according to NBC News.

“We’re all putting our heads together to try to understand what is going on,” Dr. Jorge Bezerra, director of the Pediatric Liver Care Center at Cincinnati Children’s Hospital, told the outlet.

Complicating matters, the CDC said the number of reported hepatitis cases in children is not higher than the baseline that would be expected in the U.S.. However, they were concerned about a sudden uptick in the United Kingdom and the fact that the pathogen — adenovirus 41 — previously caused hepatitis in immunocompromised children, while the newer cases are afflicting healthy kids.

“Are we recognizing something that happens many years at regular intervals and for whatever reasons we’re seeing it now because perhaps there is expanded use of adenovirus testing?” Dr. Butler said. “Are we seeing now some ‘catch-up’ infections as the COVID-19 mitigation are being lessened?”

The development raised questions about whether the coronavirus might be involved, but federal scientists don’t think so at this juncture. They said none of the children had evidence of prior coronavirus infection, but they are conducting serological tests to see if there are antibodies that would reveal infections that were missed.

Scientists tried to quash online speculation about the vaccines, saying the median age of cases occurred in children who are 2 years old and not eligible for the shots.

“COVID vaccination is not the cause of these illnesses,” Dr. Butler said.

For now, the CDC wants parents and doctors to be on the lookout. Signs of hepatitis may include vomiting, changes in the color of urine, or the yellowing of the skin.

The CDC issued a health advisory in April that said doctors should be on the lookout for the condition and any links to an adenovirus, though it said no one should panic.

“It’s important to remember, that severe hepatitis in children is rare even with the potential increases in cases we are reporting today,” Dr. Butler said.