Children play jump-rope on the street off 5th Avenue in New York City on March 7, 2022. - New York City has dropped several Covid-19 safety protocols, including a mask mandate in public schools and vaccination requirements for businesses.

A dangerous liver disease is spreading among kids in the US, and could be more out there nationwide.

According to LiveScience, the disease is "seemingly" related to a liver-compromising virus not caused by the infamous COVID-19.

The Centers for Disease Control and Prevention (CDC) issued a Health Alert Network (HAN) Health Advisory on Thursday to warn clinicians and public health providers of a cluster of at least nine unusual pediatric hepatitis cases and adenovirus infection.

According to the agency, the first US cases were identified in October 2021 at a "large children's hospital" in Alabama.

By November 2021, five pediatric patients were reported to have "significant" liver injury, including three with acute liver failure, who also tested positive for adenovirus, where all are previously healthy.

Two of the patients required liver transplants, with no reported deaths.

Upon further efforts to identify the extent of the virus, four additional pediatric patients were diagnosed with hepatitis and adenovirus infection, a total of nine patients admitted from October 2021 through February 2022.

Culprit Behind the Infection

Earlier this month, similar cases were reported in the UK, Spain, and Ireland.

Stat reported a number of unusual cases of serious hepatitis in young children, the causes of which are currently unknown.

Investigations from public health officials suggested that the cases of liver inflammation seem to be caused by a pathogen called adenovirus 41, a virus similar to COVID which can be transmitted through close contact, and respiratory excretions.

Adenovirus can also spread through fecal matter, as per Alabama public health.

The health agency said that adenovirus 41 typically only infects immunocompromised children, and is "not known to be a cause of hepatitis in otherwise healthy children", yet it infected even the healthy ones.

There is currently no cure for the illness, CDC added.

Adenovirus 41 often causes pediatric acute gastroenteritis, with symptoms including diarrhea, vomiting, fever, and other respiratory symptoms.

Also read: Rare Tick-Borne Virus Kills a Resident in Maine

CDC Recommendation

"It is not common to see children with severe hepatitis," said Karen Landers, district medical officer for the Alabama Department of Public Health, also a pediatrician for 45 years.

"Seeing children with severe [hepatitis] in the absence of severe underlying health problems is very rare. That's what really stood out to us in the state of Alabama."

With the range of adenoviruses that can infect people, genetic sequencing is underway to try to determine if one or multiple types of adenoviruses are implicated.

Some scientific findings suggested that while the cause for the liver disease is adenovirus infection, and although inflammation of the liver is caused by a number of factors, there may be a link to the pandemic, noting that young children may have become more vulnerable when masks were no longer required and social distancing measures were lifted.

For now, CDC recommended that medical providers test kids with hepatitis of unknown etiology using PCR tests.

This can be done on respiratory specimens, stool or rectal swabs, or blood.

However, anecdotal reports suggest that testing whole blood by PCR may be more sensitive than testing plasma by PCR, which is why the former could be considered in those unusual cases who tested negative for adenovirus in plasma samples.

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