CLAIM: A recent outbreak of unexplained hepatitis cases among children is being caused by the adenovirus vector used in some COVID-19 vaccines, including the Johnson & Johnson shot.
THE FACTS: Medical experts say this isn’t the case, mainly because the dead adenovirus used in the J&J vaccine is a different strain than the one linked to the recent hepatitis cases.
British health authorities this month have documented more than 100 cases of unexplained hepatitis, inflammation of the liver, among young children, and some social media users are suggesting the cases could be linked to J&J’s vaccine. While it isn’t clear what’s causing the illnesses, which have also been identified in the U.S., a leading suspect is adenovirus, a common group of viruses that can cause cold-like symptoms, fevers, sore throats and intestinal issues. Adenovirus was detected in 75% of the recent juvenile hepatitis cases tested, U.K. health officials have said.
Viral vector vaccines, like the J&J vaccine, use dead, nonreplicable adenovirus to help trigger an immune response, according to the Centers for Disease Control and Prevention. The AstraZeneca and Sputnik V COVID-19 vaccines also use viral vectors. Social media users are highlighting this connection to push the baseless claim that the adenovirus vector is causing the mysterious cases.
But experts say that’s not possible. Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, told The Associated Press that current evidence indicates these hepatitis cases could be caused by adenovirus type 41, which is associated with intestinal infections. The adenovirus used as a vector in the J&J vaccine is type 26. Offit added that the adenovirus used as a vector in the vaccine cannot reproduce itself in the body and spread.
“The combination of the fact that it’s not the type of adenovirus that’s expected to cause hepatitis, nor is it a virus that reproduces itself, makes the claim ludicrous,” Offit said. Dr. Mark Slifka, a professor of microbiology and immunology at Oregon Health & Science University, pointed to an April paper by researchers with Scotland’s public health department describing their initial investigation into the first Scottish cases of the sudden liver disease. The investigation noted that none of the children had been vaccinated against COVID-19, nor were the other patients in the U.K.
“What appears to be happening on social media, is that people are jumping to conclusions that are not based on current evidence,” Slifka wrote in an email. A spokesperson for Public Health Scotland also told the AP that “there is no evidence to support the claims” linking the juvenile hepatitis cases to COVID-19 vaccines. Further, no increased risk of hepatitis was identified in clinical trials of the vaccines, or after emergency use authorization allowed many people to be vaccinated, Slifka noted.
Adenovirus is currently circulating in children at higher than average levels after dropping during the pandemic. One theory being explored is that children who weren’t exposed to adenovirus over the last two years as COVID-19 restrictions were in place may now be getting hit harder upon exposure.
— Associated Press writer Sophia Tulp in Atlanta contributed this report.