Scientists May Have Found the Culprit Behind Mysterious Hepatitis Outbreaks in Kids

Several teams of scientists believe they have uncovered a possible cause of Rise of Mystery A severe hepatitis that hospitalized and killed children around the world last year. to three In a study published this week, the group found evidence that a common but not usually pathogenic virus was strongly associated with cases, likely fueled by co-infection with other common viruses. It is also possible that the children affected were genetically unlucky.

Earlier last year, UK health officials said first reported above A cluster of severe hepatitis, with cases dating back to fall 2021. Hepatitis is a general term for inflammation of the liver, often accompanied by symptoms such as fever, fatigue, and jaundice (yellowing of the skin and eyes). Severe cases can lead to complete liver failure or death. These children did not test positive for any known cause of hepatitis, including the unrelated group of viruses named after the condition.

Will report other locations soon similar cluster.By July 2022, according to world health organizationSince then, more than 1,000 cases of this severe, unexplained childhood hepatitis have been reported in 35 countries. Most of the children were hospitalized. About 5% became ill and required a liver transplant. As a result, 2% eventually died.

There are various theories about the origin of these clusters. Many, but not all, children tested positive for adenovirus. Adenoviruses are commonly encountered microorganisms that can cause disease. Some people have recently been infected with SARS-CoV-2, the cause of covid-19. However, the harm caused by these viruses was not accompanied by the severe liver damage normally seen in these children, indicating that other catalysts were at work here. The theory debunked blamed the covid-19 vaccine, but many victims the children were too young received the shot.

of three paper It was published In this week’s Nature, a team of independent scientists explains: Evidence points to a common culprit, adeno-associated virus type 2 (AAV-2), which did not work alone. Each group found that the majority of cases they studied were recently infected with AAV-2, a much higher rate than similarly matched controls or those who developed hepatitis from known causes. Some teams have also found indirect evidence that AAV-2 is infecting the children’s livers and resulting organ damage.

AAV-2 is strange, among others microbes. This is a satellite virus. That is, it can make more of itself in a cell only if another “helper” virus is infecting the same cell. As the name suggests, adenovirus is her AAV-2’s common helper virus, but herpes virus can also be its partner. In many of these children, scientists have also found these helper viruses, sometimes multiple viruses.

AAV-2 isolated from affected individuals The children do not appear to be genetically different in any significant way from other known strains, but one study by British researchers suggest Another important factor behind the clusters: most cases carried the same variants in genes known to affect immune responses, with a higher proportion than the general population. Having this variant may have made children more vulnerable to scenarios that are less likely to lead to hepatitis, the authors say.

“On rare occasions, a full storm-like event could turn out to be happening,” said Charles Chiu, an infectious disease specialist at the University of California, San Francisco. The authors behind the study that examined Said New York Times.

These studies alone Prove that AAV-2 is the cause of the cluster. For one, they were all based on small samples of patients, and two of the many countries with reported cases (the United States and the United States)K.).there is Exactly how AAV-2 can do this in children is still unanswered.Also, I’m not sure why these clusters occur when they occur.

The relative lack of other common infections in the first few years of the pandemic led to an immunological gap, and as people began to socialize regularly again, these diseases (and their rare complications) ) may have been temporarily larger than usual. Data still from the United States Indicated The recorded rate of unexplained hepatitis cases in children has not increased from pre-pandemic baselines last year.In other words, AAV-2 always rare but consistent It was caused by hepatitis, but I finally realized it because I was looking for it. It is also possible that some countries experienced a true surge last year while others did not.

Thankfully, the reported incidence of these unexplained hepatitis cases is The imminent crisis appears to be over, as it peaked last summerBut to confirm what these scientists have found, and to better understand what happened to these children, and whether something can be done to prevent or reduce similar risks, further research is needed. need to do research. future case.