The U.S. Centers for Disease Control and Prevention has issued a health alert regarding severe hepatitis in young children after several cases have been reported in Alabama. Public health officials in the United Kingdom are also investigating more than 100 cases. While the source of the infections is unknown, “a possible association between pediatric hepatitis and adenovirus infection is currently under investigation,” according to the CDC alert.
Internationally, 108 cases have been reported in the United Kingdom, with 79 cases occurring in England. There are three documented cases in Spain, and similar cases are being reported in Denmark and the Netherlands, according to an article in Science. In the United Kingdom, cases have been reported in children up to 16 years old, but most affected children are between 2 and 5 years old. Eight children in the United Kingdom have required liver transplants.
On April 14, the CDC said that nine cases have been recorded in Alabama since the fall of 2021. All of these cases have been in children between 1 and 6 years old, and two children have needed liver transplants. Two additional cases have been reported in North Carolina, according to Stat News, and both children have since recovered.
Hepatitis A, B, C, D, and E viruses—common causes of hepatitis—have been ruled out in the U.K. and Spanish cases. More than three-fourths (77%) of the children sickened in the United Kingdom and all nine cases in Alabama have tested positive for a form of the adenovirus. While adenovirus can cause hepatitis in children, it is usually in those who are immunocompromised.
The CDC health alert advises clinicians who have cases of unexplained hepatitis in children to test for adenovirus and report these cases to the CDC as well as state public health authorities. The agency recommends nucleic acid amplification testing to detect adenovirus using respiratory swabs, stool samples or rectal swabs, or blood.
Officials are exploring whether these cases are linked to a version of the virus called adenovirus 41, which is associated with gut inflammation. The most recent case in Alabama was reported in February, and five of the nine children in the state with these puzzling cases of hepatitis have tested positive for adenovirus 41.
There have yet to be any links among the cases in Alabama or North Carolina, and investigators in the United Kingdom have also not found any connections in their cases, STAT News reports.
“CDC is working with state health departments to see if there are additional U.S. cases and what may be causing these cases,” said Kristen Nordlund, a CDC spokesperson, in a statement to STAT News. “At this time, adenovirus may be the cause for these, but investigators are still learning more – including ruling out the more common causes of hepatitis.”
Looking for other explanations
None of the children in the United States with hepatitis had COVID-19, but a few children in the United Kingdom have tested positive for the virus; none of these children have received the COVID-19 vaccine.
While the U.K. Health Security Agency says their investigation “continues to point toward a link to adenovirus infection,” they are also considering other contributing factors such as an environmental cause or COVID-19.
“COVID has been consistently shown to increase liver test numbers,” Nancy Reau, MD, the section chief of hepatology at Rush University in Chicago, said in an interview with this news organization. “It has been shown to cause other organ involvement besides just pulmonary symptoms and respiratory failure. As this virus evolves, it might be that in children, it is more able to present as hepatitis.”
A version of this article first appeared on Medscape.com.
This article was updated 4/22/22.