Mysterious Hepatitis Outbreak

 

Last week the Centers for Disease Control and Prevention issued a Health Alert Network Health Advisory warning pediatricians and other health providers to keep their eyes peeled for new cases of acute hepatitis. Lucy Hicks reports that 11 young children in two states — all previously healthy — developed the liver inflammation in the last 6 months, some quite severely:

On April 14, the CDC said that nine cases have been recorded in Alabama since the fall of 2021. All of these cases have been in children between 1 and 6 years old, and two children have needed liver transplants. Two additional cases have been reported in North Carolina, according to Stat News, and both children have since recovered.

 

The mysterious outbreak is occurring simultaneously in Europe:

Internationally, 108 cases have been reported in the United Kingdom, with 79 cases occurring in England. There are three documented cases in Spain, and similar cases are being reported in Denmark and the Netherlands, according to an article in Science. In the United Kingdom, cases have been reported in children up to 16 years old, but most affected children are between 2 and 5 years old. Eight children in the United Kingdom have required liver transplants.

 

Infectious hepatitis is most commonly caused by viruses, although inflammation and liver damage can also be due to alcohol use, illicit drug use, exposure to environmental toxins and synthetic chemicals, and certain medications. Laboratory analysis has failed to reveal the usual viral suspects known to cause acute liver infections: hepatitis A, hepatitis B, and hepatitis C. Scientists at the CDC have identified adenovirus 41 as the possible culprit of this outbreak:

Adenoviruses are doubled-stranded DNA viruses that spread by close personal contact, respiratory droplets, and fomites. There are more than 50 types of immunologically distinct adenoviruses that can cause infections in humans. Adenoviruses most commonly cause respiratory illness but depending on the adenovirus type they can cause other illnesses such as gastroenteritis, conjunctivitis, cystitis, and, less commonly, neurological disease. There is no specific treatment for adenovirus infections.

Adenovirus type 41 commonly causes pediatric acute gastroenteritis, which typically presents as diarrhea, vomiting, and fever; it can often be accompanied by respiratory symptoms.

 

Most of the hepatitis cases have occurred in children under six. While most tested positive for adenovirus, a handful showed evidence of COVID-19, according to the World Health Organization:

The United Kingdom has recently observed an increase in adenovirus activity, which is co-circulating with SARS-CoV-2, though the role of these viruses in the pathogenesis (mechanism by which disease develops) is not yet clear. No other epidemiological risk factors have been identified to date, including recent international travel. Overall, the aetiology of the current hepatitis cases is still considered unknown and remains under active investigation. Laboratory testing for additional infections, chemicals and toxins is underway for the identified cases

 

This new variety of hepatitis appears to spread like hepatitis A — from touching infected people or contaminated surfaces and then ingesting the virus unsuspectingly by mouth, or by eating contaminated food (such as undercooked shellfish). Before the vaccine to prevent it became widely available in the late 1990s — the 2-dose series is now given routinely to children at 12 and 24 months old — hepatitis A was considered a mild disease in children, causing minimal if any symptoms in most kids who were infected with the virus. Complications requiring liver transplantation or resulting in death were exceedingly rare. (Hepatitis A is a much more serious infection in adults, which explains the rationale for immunizing young kids who might be asymptomatic but risk passing along the virus to others without knowing it.)

Meredith Wadman describes a theory which might explain the current outbreak:

“The leading hypotheses center around adenovirus—either a new variant with a distinct clinical syndrome or a routinely circulating variant that is more severely impacting younger children who are immunologically naïve,” the Scottish investigators wrote.

Isolation of the youngest children during the pandemic lockdown may have left them immunologically vulnerable because they haven’t been exposed to the multiplicity of viruses, including adenoviruses, that typically attend toddlerhood. “We are seeing a surge in typical childhood viral infections as children come out of lockdown, [as well as] a surge in adenovirus infections”—but can’t be sure that one is causing the other, says Will Irving, a clinical virologist at the University of Nottingham.

 

Pediatricians are trained to detect the symptoms (abdominal pain, vomiting, diarrhea, diminished appetite, fatigue, sometimes fever) and signs (liver tenderness and jaundice) of hepatitis in their patients. While scientists in the U.S. and around the world are monitoring the situation as it develops, parents and caretakers should be reassured that the number of children who develop hepatitis from any cause is extremely small. It’s also good to know that the most effective layer of protection against the infection may also be the simplest: good hand washing with soap and water.

 

(Google Images)

 

source http://www.thepediablog.com/2022/04/26/mysterious-hepatitis-outbreak/