What is hepatitis and what do we know about mysterious cases in children – explainer


On April 5, the United Kingdom reported an unexpected and significant increase in cases of severe acute hepatitis of unknown origin in young, previously healthy children, all under 10 years of age.

Since then, 11 other countries, including Ireland, the US, Israel, the Netherlands, Romania and, as of Tuesday, Japan, have reported an increase in cases to the World Health Organization (WHO). On Wednesday it was reported Canada is also investigating an undisclosed number of cases. to see if they are related to the outbreak.

Affected children range from one month to 16 years. One child died and about 10% of cases required a liver transplant, the WHO said.

Most of the cases are in the UK (114 cases), with approximately 200 cases reported in total. The true number may be higher if there are affected children who do not show severe symptoms and therefore have not been brought to hospital for testing.

What is hepatitis?

Hepatitis is inflammation of the liver, which can lead to a variety of health problems, including cancer and liver failure, and can be fatal. The liver is crucial as it removes toxins from the blood, participates in metabolism and regulates blood coagulation, among other functions.

Hepatitis has several causes.

The most common are viruses, with hepatitis A, B, C, D and E being the main virus strains involved. These viruses differ in terms of how they are transmitted, their geographic spread, symptoms (not everyone develops symptoms), and severity, but they all lead to hepatitis. There are vaccines against some of these virus strains.

Alcohol, certain medications, and immune system disorders can also cause hepatitis.

Sometimes hepatitis has no known cause, which is what is being seen in the cases in children reported to the WHO. However, these severe cases resulting in liver failure are especially rare in children, so when doctors in the UK saw an increase in these cases without cause, they became concerned. This led to the report to the WHO and to other countries becoming alert on the subject.

Common hepatitis viruses have not been detected in any of the affected children.

Associate Professor Asha Bowen, a physician at Perth Children’s Hospital in Australia and an infectious disease researcher at the Telethon Kids Institute, said: “This is definitely unusual, and I can’t think of many times in my career where we’ve been faced with something like this. ”

“What’s unusual is that it’s fulminant hepatitis, which basically means the liver has completely failed in these kids,” Bowen said. “That is extremely rare in childhood. And it has put us all on high alert.”

What do we know about this mysterious hepatitis?

The children were generally healthy before they got sick and were diagnosed. The WHO described his hepatitis as “severe and acute.”

Many of the children suffered from gastrointestinal symptoms such as abdominal pain, diarrhea and vomiting just before they were diagnosed. Many also had jaundice, a condition that can make the skin and eyes look yellow and can be caused by liver damage.

Several investigations are being carried out on the possible causes of the mysterious hepatitis, but nothing has been confirmed.

Adenoviruses, which are common and cause what people describe as a cold and symptoms like sore throat, fever and diarrhea, were detected in more than 70 of the children. Covid-19 was also detected in 20 cases.

But the WHO said in its latest report on the cases that while adenovirus is currently a hypothesis as the underlying cause, it “does not fully explain the severity of the clinical picture.” The strain of adenovirus, known as type 41, which is seen in many of the children, has not previously been linked to severe hepatitis.

“While there have been reports of cases of hepatitis in immunocompromised children with adenovirus infection, adenovirus type 41 is not known to be a cause of hepatitis in healthy children,” the WHO said.

Bowen, who is also co-chair of the Australasian Infectious Diseases Society, said the adenovirus theory is the most likely explanation so far, but “if that’s the absolute causative agent, there’s still quite a bit of uncertainty about that.”

Other research is examining whether environmental factors or other viruses or organisms may be involved.

Director of the European Center for Disease Prevention and Control, Dr. Andrea Ammon, told reporters during a briefing on Tuesday that another hypothesis being investigated is whether the lockdowns may have weakened children’s immunity due to less exposure to pathogens.

The WHO said “hypotheses related to side effects of Covid-19 vaccines are currently not supported” as most of the affected children did not receive the Covid-19 vaccine as they were too young.

What’s the health advice in the meantime?

Countries have been urged to be alert to any case of hepatitis in children with no apparent cause. The WHO recommends that these children have blood, urine, stool and respiratory tract samples taken, as well as liver biopsy samples.

“Other infectious and non-infectious causes should be thoroughly investigated,” the WHO said.



Reference-www.theguardian.com

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