The COVID-19 pandemic is not over, and yet another type of hepatitis of unknown cause has emerged.
According to the World Health Organization (WHO) and the European Center for Disease Control and Prevention, nearly 200 cases of unexplained childhood hepatitis have occurred in at least 12 countries around the world, which has aroused the concern and concern of many countries.
WHO says that while adenovirus is currently a hypothesis of a potential cause, it does not fully explain the severity of the clinical situation. In addition, hypotheses related to the side effects of the COVID-19 vaccine are not currently supported, as most affected children are not vaccinated because they are too young.
Currently, WHO, the European Centre for Disease Control and Prevention and multinational medical experts around the world are studying the causes of the disease and exploring response measures and options.
How many cases of hepatitis of unknown cause have been detected in children?
On 5 April 2022, the UK reported to WHO for the first time that there had been a significant increase in the number of cases of children with severe acute unexplained hepatitis in the UK. After April 8, similar cases began to appear in Ireland, Spain and other places in Europe.
WHO mentioned this in a notification on 15 April and provided an overview of the latest unidentified cases of hepatitis in a notification dated 23 April.
As of 21 April, 169 children in at least 12 countries have contracted hepatitis of unknown cause, including 11 in the European Region and 1 in the Americas, according to WHO data. On 26 April, the European Centre for Disease Control and Prevention released higher estimates, with nearly 200 such cases already occurring worldwide.
On April 26, Japanese media such as the Japan Times reported that the first suspected case in Asia appeared in Japan. On 27 April, a number of Canadian media outlets, including the Canadian Broadcasting Corporation, reported that Canada was investigating an unknown number of cases to determine whether they were among the above-mentioned cases of unexplained hepatitis.
Why is hepatitis of unknown cause a concern?
Mild childhood hepatitis is not unheard of, so why is this unknown case of hepatitis causing concern? A number of foreign media reported that one of the reasons for this is that such unknown hepatitis can have serious symptoms.
A WHO notification dated 23 April indicates that patients with unexplained hepatitis range in age from 1 month to 16 years and have symptoms including significant elevation of liver enzymes with jaundice and sometimes gastrointestinal symptoms such as diarrhoea, vomiting and abdominal pain, with most cases without fever.
Children are usually healthy before being diagnosed with unexplained hepatitis, but illness can be severe enough to require a liver transplant or even die. In its bulletin on 23 April, WHO mentioned that of the cases of unknown hepatitis, 17 required liver transplantation and at least 1 died.
"It's absolutely unusual. I say this because it's fulminant hepatitis, which basically means that the livers of these children have completely failed, which is extremely rare in childhood, and it puts us all on high alert. Asha Bowen, a researcher at the Telethon Kids Institute, an Australian medical research institute, said.
According to CNN, the U.S. state of Wisconsin is investigating whether several cases of unidentified hepatitis are linked to such unidentified hepatitis, including 1 death. If the cause of this death is confirmed to be related to such unidentified hepatitis, it will be the first death case in the United States to be related to such unexplained hepatitis.
Another reason for concern is that current studies have shown that most people with this type of hepatitis are children and are not associated with the common virus that causes hepatitis.
On November 6, 2020, in Shanghai, in the medical device and health care exhibition area of the Expo, GlaxoSmithKline exhibited the recombinant hepatitis B vaccine. Infographic/IC photo
The most common cause of hepatitis is infection with viruses, of which hepatitis A, B, C, D and E are typical viral hepatitis, but none of the affected cases of children have been detected with these common hepatitis viruses.
Alcohol, certain drugs, and immune system disorders can also cause hepatitis. Sometimes, hepatitis can also be caused by unexplained causes. However, such severe cases of liver failure are particularly rare in children.
"While the current number of cases of such unidentified hepatitis remains a minority, the majority of patients are children, which is the most worrying. At the same time, its severity is also worrying. Maria Butti, president of the European Association for the Study of the Liver, said.
Is unexplained hepatitis associated with adenovirus?
At present, the etiology of such cases of hepatitis in children remains undetermined, with adenovirus infection being by far the most likely explanation.
Adenoviruses are a common class of viruses that spread from person to person and usually trigger a range of mild illnesses, including colds, vomiting, and diarrhea. The Daily Telegraph reports that in rare cases, adenovirus can cause hepatitis.
In its latest notification on cases, WHO said adenovirus had been detected in at least 74 cases. The UK survey showed that information from patient samples and surveillance systems pointed to an unknown cause of hepatitis to adenovirus infection, with 77% of testing cases testing positive for adenovirus.
Susan Hopkins, chief medical adviser to the Health Security Agency, said UK health officials were still studying a range of possible factors contributing to the increase in cases of unexplained hepatitis, but the "most likely" cause was adenovirus infection.
The Health Safety Agency also raised other possibilities of adenovirus infection in its April 25 briefing, such as the presence of co-infections that have not yet been detected, or new strains of adenovirus that have changed their characteristics.
The U.S. health department holds a similar view. The Centers for Disease Control and Prevention said in a Statement on April 21 that adenovirus may be the cause based on what is currently understood, but researchers are still learning more.
However, WHO says that while adenovirus is a hypothesis of potential cause, it does not fully explain the severity of the clinical situation. Although there have been previous cases of hepatitis in immunocompromised children infected with adenovirus, no cases have been found that cause hepatitis in healthy children.
Philippa Easterbrook, a WHO expert on hepatitis, believes that although about 74 of the cases tested have detected adenoviruses, it is unusual for adenoviruses to cause severe symptoms of such hepatitis.
In addition, there are also research institutes that do not agree that adenovirus infection is the cause of such hepatitis.
On April 26, local time, the Italian Institutes of Advanced Health released a study on the recent emergence of hepatitis in children of unknown etiology in Europe and the United States and other countries. The report argues that some researchers have suggested that the likelihood of hepatitis caused by adenovirus is extremely low.
Unexplained hepatitis related to COVID-19?
IN ITS april 23 notification, WHO also noted that the new coronavirus was detected in 20 cases.
There is a view that unknown hepatitis is caused by the side effects of the NEW CROWN vaccine, which has been ruled out by some current studies.
WHO said "the hypothesis related to the side effects of the COVID-19 vaccine is not currently supported" because most affected children are not vaccinated because they are too young. The UK Health Safety Agency and the Italian Institutes of Health have also said that this unexplained hepatitis is not related to the side effects of the new crown vaccine.
There are also views that unknown hepatitis is related to COVID-19 prevention and control measures. In response, the UK Health Security Agency said in its April 25 briefing that there may be a cofactor that causes normal adenovirus to show more severe clinical symptoms in children. For example, during the COVID-19 epidemic prevention and control period, children have reduced their exposure to adenovirus, and with the liberalization of COVID-19 prevention measures, children have become more susceptible to infection.
Research is ongoing on whether unexplained hepatitis is linked to the coronavirus.
In Israel, for example, 12 cases have been identified to date that meet who's definition of current unidentified cases of hepatitis in children.
"After we ruled out all the possibilities, what we found in common for all the cases was that all the cases were infected with the new coronavirus about three and a half months before the emergence of unknown hepatitis," Dr. Yele Moser Grasberg, head of the pediatric liver transplant department at the Petatikwa Schneider Children's Medical Center in Israel, told the Israeli media Haaretz, "but I don't think it can be said that all these cases are phenomena that appeared after the new crown virus infection." ”
Speaking at a briefing on April 25, Andrea Amon, director of the European Center for Disease Control and Prevention, said, "We don't want the so-called anchor bias to miss out on other causes if we focus only on the possibility that COVID-19 is the cause." ”
Other possibilities exist for the etiology of such unknown hepatitis. According to the UK Health Security Agency, hepatitis of unknown etiology may also be age-related. Infants have milder symptoms after contracting the virus, but as they age, these children who have been infected with the virus experience a more severe response.
What are the precautionary recommendations for hepatitis in children of unknown cause?
WHO recommends that normal hygiene measures, such as thorough handwashing, including supervising children's handwashing, help reduce the spread of many common viral infections, including adenovirus. WHO has urged countries to remain vigilant about any unexplained cases of hepatitis in children and has said there is a need to thoroughly investigate other infectious and non-communicable causes.
Experts from the UK's Health Security Agency and the US Centers for Disease Control and Prevention have advised parents and guardians to be vigilant when children develop symptoms of hepatitis. In addition, maintaining good hand and respiratory hygiene and supervising thorough handwashing in young children can help reduce adenovirus transmission.
Professor Peter Collinion, an Australian infectious disease specialist, believes that the best protection for families with young children in the short term is to keep them away from other sick people and maintain good hygiene practices.
In addition, there are cases of hepatitis of unknown cause in Beijing on the Internet, which have been verified by the Beijing Municipal Health Commission, which is false information. In view of the relevant case information recently reported abroad, in order to prevent the occurrence of the disease and protect the health and life safety of children in the capital region to the greatest extent, the Beijing Municipal Health Commission issued the "Notice on Strengthening the Treatment of Hepatitis Cases of Unexplained Children", with the purpose of prompting relevant medical institutions to increase vigilance, if such cases occur, it is necessary to find out the causes as soon as possible and strengthen treatment.
Reporter | Vermilion red
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