The Public Health Agency of Canada (PHAC) has confirmed 10 cases of acute severe hepatitis in children.
The agency posted an update on their website Friday, confirming three cases in Alberta, two in Manitoba, four in Ontario, and one in Quebec.
The children, who are between one and 13 years old, became sick between November 3, 2021 and April 23, 2022, according to PHAC.
All of the diagnosed children were hospitalized. Two of them needed liver transplants. No deaths have been reported so far.
Hepatitis is an inflammation of the liver. Depending on the cause, the agency says the disease can be sudden and progress to liver failure over a few days to weeks.
“Some types of hepatitis can be treated and most cases recover. Acute, severe hepatitis in children is a rare condition in Canada, and in many cases, an underlying or contributing cause is not known,” the website states.
What is causing severe acute hepatitis in children?
The health agency says that the exact cause for this illness is not yet known, and investigators are still considering the possible causes of acute hepatitis.
However, one possible cause being explored is adenovirus, a common virus, which is known to cause cold or flu-like illness or gastroenteritis in children who are infected.
Investigators are also looking into other possible contributing factors such as exposure to toxins or other infections.
Could COVID-19 be the cause of hepatitis in kids?
COVID-19 may be behind the severe hepatitis cases in children according to a report posted last Saturday on medRxiv ahead of peer review.
Children with COVID-19 are at significantly increased risk for liver dysfunction afterward, the report said.
But most of the children with acute hepatitis did not report a previous COVID-19 infection. Instead, the majority were found to be infected with an adenovirus called 41F, which is not known to attack the liver.
READ MORE: Canada detects severe hepatitis of ‘unknown origin’ cases in kids. What is it?
It is possible that affected children, many of whom were too young to be vaccinated, may have had mild or asymptomatic COVID infections that went unnoticed, a separate team of researchers suggested in The Lancet Gastroenterology & Hepatology.
If that’s true, lingering particles of the coronavirus in the gastrointestinal tract in these children could be priming the immune system to overreact to adenovirus-41F with high amounts of inflammatory proteins that ultimately damage the liver, the researchers theorized.
Side effects from COVID-19 vaccines however, are not suspected since the vast majority of the affected children were too young to receive COVID-19 shots, according to the World Health Organization.
What are the symptoms?
The government has provided a list of symptoms parents should look for in their kids on their website.
They include yellowing of the skin or eyes, abdominal pain, nausea, vomiting, dark urine, light-colored stools, loss of appetite, fever, and fatigue.
The government is also advising parents to encourage children to wash their hands often, avoid people who are sick, and avoid touching their eyes, nose or mouth.
What is Canada's health agency doing?
The PHAC says it’s working with provinces, territories and international partners to investigate any reported cases of acute severe hepatitis in children not caused by known hepatitis viruses.
“All provinces and territories are working to identify and report potential cases to PHAC. This will help to further define the national scope in Canada, and help determine if cases in Canada are related to other cases reported around the world,” the agency stated.
READ MORE: 348 probable cases of acute hepatitis in children reported globally: WHO
At this time, the agency does not know if there has been a spike in acute severe hepatitis cases in children “not caused by known hepatitis viruses.”
“We are analyzing Canadian hospitalization data to determine the number of cases that we would normally see in Canada over time. This baseline information will allow us to determine if we are seeing an increase in cases reported,” the agency said.
Severe hepatitis cases around the world
Reuters reported on May 20 that at least 600 children in at least 34 countries have developed cases of sudden severe liver inflammation or acute hepatitis.
As of May 18, at least 175 children in the UK and 180 in the United States have become sick since October 2021, the majority of them younger than five-years-old.
In the United States, more than 90 per cent of affected children have been hospitalized. Most have recovered, but at least five died, according to the U.S. Center for Disease Control and Prevention. Worldwide, more than two dozen children have needed liver transplants.
Most cases have been reported since April.
—With files from Reuters