Health officials in the UK say they are focusing on a possible adenovirus link to cases of severe hepatitis—or liver inflammation—in children.
There have been at least 169 cases of “acute hepatitis of unknown origin” recorded worldwide, and one death, while 10 children in the UK alone have needed liver transplants.
Hepatitis can be life-threatening if left untreated.
The cause of the spike in cases among children remains unknown, but British health officials say a strain of adenovirus called F41 could be the most probable cause.
Adenovirus, a viral infection that usually causes the common cold, was detected in 75 percent of the confirmed cases tested, the UK Health Security Agency (UKHSA) said in a statement on Monday.
Adenovirus, a common group of viruses, is now circulating in children at higher than average levels after dropping to unusually low levels during the pandemic. One avenue of inquiry being explored is that the outbreak may be linked to a surge in common viral infections after COVID-19 restrictions were phased out. Children who weren’t exposed to adenovirus over the last two years may now be getting hit harder when they are exposed to the viruses.
“Information gathered through our investigations increasingly suggests that this rise in sudden onset hepatitis in children is linked to adenovirus infection,” said Dr. Meera Chand, director of clinical and emerging infections at UKHSA. “However, we are thoroughly investigating other potential causes.”
The British health agency said in a briefing Monday that there may be “a cofactor causing a normal adenovirus to produce a more severe clinical presentation in young children.”
This could be an “increased susceptibility due to reduced exposure during the pandemic, prior SARS-CoV-2 or other infection, or a yet undiscovered coinfection or toxin,” it said.
“Alternatively, there may have been emergence of a novel adenovirus strain with altered characteristics,” UKHSA said.
The majority of children affected are under the age of 5 and have presented symptoms of gastroenteritis illness—diarrhoea and nausea—as well as jaundice, which is the yellowing of the skin and whites of the eyes.
UK public health officials have ruled out any links to COVID-19 vaccines, saying none of the affected children were vaccinated.
The Centers for Disease Control and Prevention (CDC) issued a health advisory last week after children in Alabama were discovered to have adenovirus and hepatitis infections.
The CDC said that five pediatric patients with significant liver injury, including three with acute liver failure, who also tested positive for adenovirus, were reported to the agency by an Alabama hospital.
The CDC added that the children were previously healthy and that none had COVID-19.
Two cases were also identified in North Carolina, health department officials said.
Cases have also been found in Denmark, Spain, and the Netherlands, according to the European Center for Disease Prevention and Control.
