April 4, 2023 – Researchers have found that co-infection by several common viruses could have caused a mysterious hepatitis outbreak in children world wide.
As of October 2021, greater than 1,000 children in 35 countries have been affected by these infant hepatitis cases. Although most kids survived, of the roughly 350 patients identified within the United States as of May 2022, 22 required a liver transplant and 13 died.
Most of those children were under 6 years old.
Not only are these cases of hepatitis acute and severe, but their cause can be a mystery. They don't fit into the common categories of liver inflammation often known as hepatitis A through E.
Now researchers have identified a possible offender. They identified a virus strain called adeno-associated virus type 2 (AAV2) because the major player within the outbreak. And in the event that they are right, AAV2 isn't acting alone.
In fact, this virus isn't strong enough to cause these severe cases without help. Instead, affected children will need to have at the least one other “helper virus” at the identical time, akin to a human adenovirus (which may cause symptoms much like a chilly or flu). according to CDC), Epstein-Barr virus and/or human herpesvirus 6.
The new study was published online within the journal on March 30 Nature.
Reference to the pandemic
According to the researchers, there isn't any evidence that the illnesses are linked to the virus that causes COVID-19, however the pandemic could still be a consider these infections. Because many children weren't exposed to the viruses related to the hepatitis cases as they normally would have been during lockdowns and social isolation, they didn't develop immunity to them.
“So it's possible that they were suddenly and briefly exposed to multiple viruses after restrictions were lifted,” said lead study writer Charles Chiu, MD, PhD, a laboratory medicine and infectious disease specialist on the University of California San Francisco School of Medicine.
This constellation and the shortage of a robust immune system to cope with these specific viruses “would have increased their risk of becoming seriously ill.”
William Balistreri, MD, a pediatric hepatitis specialist who was not involved within the study, agreed that this was possible.
This is a widely held theory, especially given the timing of nearly all of cases, which peaked at the peak of the COVID-19 pandemic and associated isolation measures,” said Balistreri, who is also professor of pediatrics and director emeritus of the Pediatric Liver Care Center at Cincinnati Children's Hospital Medical Center.
What you should pay attention to with children
His most important message for parents and medical staff is: “The key is education and reassurance,” Balistreri said.
Vigilance is also advised if a child exhibits symptoms that often occur shortly before hepatitis, including respiratory symptoms, nausea, vomiting, diarrhea and abdominal pain. Even if Jaundice or yellowing of the eyes due to jaundice (scleral icterus) occurs, hepatitis must be suspected.
“The excellent news that almost all children with acute hepatitis get well gives us reassurance. Should a case occur, it's advisable to maintain the kid well hydrated, offer him a standard weight-reduction plan and avoid medications that could possibly be broken down by the liver,” Balistreri said, noting that COVID vaccination is “strongly advisable.”
Working on solving the puzzle
Chiu and his colleagues were not completely in the dark at first. They knew from previous research that adenoviruses might be involved. So they used genome sequencing and other modern technologies to look for the virus in 27 blood, stool and other samples from 16 children with this severe hepatitis. They also wanted to know what other viruses might be present.
And for comparison, they looked for the same viruses in a group of 113 children without this severe hepatitis of unknown cause.
Their findings were supported by two other studies conducted at different institutions and published at the same time in the same journal. One of them was a Genomic study Confirmation of the presence of AAV2 and other suspected viruses, and the other was a Genomic and laboratory study to further substantiate the results.
The average age of the 16 affected children studied by Chiu and colleagues was 3 years. About half were boys. These children were diagnosed with severe hepatitis from the first diagnosis on October 1, 2021, to May 22, 2022.
Key findings
Of the three studies conducted in Nature, through the use of various diagnostic instruments, A constant presence of adeno-associated virus type 2 was found in all or almost all children, while “helper viruses” of various types were also detected.
What was also striking in the studies was: What not found. In a comparison group of 113 children, AAV2 was much less common in those with diagnoses other than the mysterious ailments – including stomach flu, hepatitis of known origin, and those hospitalized for liver failure.
There was also little evidence of the “helper viruses”.
“I'm pretty confident that we've identified the important thing viruses” because they did extensive genetic sequencing “to search for possible infections by any virus or non-viral pathogen,” Chu said.
Moving forward
The next steps in research could transcend determining the presence of those viruses and aim to find out which virus or viruses contribute most to acute hepatitis in children.
In addition, a study was conducted within the UK that identified a particular genetic factor related to the condition, and Chiu and his colleagues may investigate this query further.
They also said they might investigate other things related to the COVID pandemic, including whether and for a way long COVID suits into it and whether there may be a resurgence of other viruses akin to respiratory syncytial virus (RSV) and influenza.