UNIDENTIFIED HEPATITIS IN CHILDREN

UNIDENTIFIED HEPATITIS IN CHILDREN

By SNEHA MAVIS

Since January 2022, doctors have been treating unexplained occurrences of acute hepatitis in young children, a few of whom have undergone liver transplants and some of whom have passed away. The reason for the outbreak, which began in Scotland and extended to over 1,000 cases worldwide, has remained unknown.

According to two recent, separate, but related studies, the unexplained occurrences of hepatitis in children are probably caused by one, two, or more interacting viruses, as well as maybe by a gene mutation.

Both investigations were done in the United Kingdom, one at the University of Glasgow in Scotland and the other at the UCL Great Ormond Street Institute of Child Health in London.

The investigations found high quantities of Adeno-associated virus 2, or AAV2, the genetic material in nearly all affected children, but not in healthy children served as controls. AAV2 is extremely prevalent, infecting almost everyone in childhood, and it may stay in the body at low levels permanently. AAV2 is thought to be safe and has not been linked to any illnesses, adding to the enigma. AAV2's presence is intriguing because it can only multiply in the presence of other adenoviruses or herpes viruses, raising the possibility that one of them is responsible for these unexplained episodes of hepatitis.

Researchers from Scotland did discover evidence of human herpes virus 6B  and likely adenovirus HAdV species C and F. HAdV C and F were detected in six of the nine affected children, and HHV6B in three of the nine.

A gene mutation called HLA-DRB1*04:01 was also present in eight of the nine children in the Scottish study who had acute hepatitis. Only about 15.6% of Scottish blood donors have the trait.

The Scottish study's lead author, Professor Emma Thompson, told "The first step is for additional cohorts around the world to screen for AAV2 and the HLA relationship". We already have two separate studies that support this, but it will be interesting to see if this holds true in other nations as well, she added.

Prof. Thompson proposed the following explanation for why children may be the only ones who are experiencing these unexplained incidents of hepatitis: "I believe this is a ‘multi-hit' scenario, in which the children have the underlying vulnerability and are being exposed to both HAdV and AAV2 for the first time, whereas most adults have already been exposed to these viruses."