Acute childhood hepatitis: what is behind the increase in cases?

It is the hypothesis that gains more force, but is still under investigation, nuance the experts. That, after the increase in cases of acute childhood hepatitis of unknown origin that are being reported by various countries, including Spain, it’s not just an adenovirusbut that children -more protected by the masks they were forced to wear during the Covid-19 pandemic- are now more exposed to this pathogen that causes a wide range of diseases and the mysterious pictures that are being registered.

In total, at least 228 cases in 20 different countries. An increase that confuses doctors and is causing them concern, he admits to El Periódico de España, a newspaper of the same group, Prensa Ibérica, that this newspaper, Dr. María Buti, from the Spanish Association for Liver Studies (AEEH).

This same Monday, the World Health Organization (WHO) assured that the rise of cases of acute childhood hepatitis is a “very urgent” issue to which they are giving “absolute priority”. “It is very urgent and we are giving absolute priority to this and to work very closely with the European Center for Disease Prevention and Control (ECDC, for its acronym in English) in management and coordination”, indicated from Lisbon the regional director of Emergencies of the WHO, Gerald Rockenschaub. With data from Tuesday, the WHO reported at least 228 cases and the affected countries are already twenty, almost double the number reported 10 days ago.

Between January 1, 2022 and April 29, 2022, in Spain they have detected 22 cases under investigation of severe unaffiliated hepatitis in people between 0 and 16 years of age with no epidemiological link between them, as reported last Friday by the Ministry of Health. Of those initially notified (April 22 report), 3 have been discarded. In four cases out of eight analysed, in which results are available, a a positive test for adenovirus.

In one case, according to the same information from the Ministry, it has been possible to determine, through genomic sequencing in the National Center for Microbiology, that the adenovirus is type 2 and the rest are pending results. As explained by the ministry headed by Carolina Darias, the epidemiology services are applying a comprehensive questionnaire to all the cases identified to date, without so far common cause found.

An active investigation

From the Spanish Association for Liver Studies (AEEH), parent of the Alliance for the Elimination of Viral Hepatitis in Spain (AEHVE), its former president, Dr. María Buti, also a collaborator of the European Center for the Prevention and Control of Diseases, admits that in international organizations there is “concern” about the increase in the number of cases. “That is what the WHO has transmitted and because, in addition, there are a number of cases of children who, although they are few, have needed a liver transplant and that is a sign of seriousness and concern,” says the specialist.

The doctor reviews what is known so far. That there has been “a very significant increase in cases” of this acute hepatitis of unknown cause. Until last April 21, 169 cases in the world, she details her. Currently, according to WHO data, there are already at least 228. Another 50 suspected cases are being investigated and at least four regions are affected (most of the cases were reported in Europe, but there have also been notifications in Americas, Asia-Pacific and South Asia).

The first ten were notified by the United Kingdom to the international organization on April 5, in children under ten years of age without previous ailments, and since then infections have also been detected in Spain, Israel, Denmark, Italy, United States and Belgiumamong other countries.

“Some of these children would have needed specialized treatment in liver units and, in some cases, a transplant. Most of them debuted with gastrointestinal symptoms, diarrhea, vomiting, intestinal discomfort… A few days before presenting acute hepatitis. As a result of this, both in the WHO and in the ECDC, an alert was created and the probable cases were defined: children under 16 years, with acute hepatitis, with elevated transaminase values ​​above 500 and the WHO has been working on this. In the definition of these cases so that they can be reported and this can be helpful in knowing the cause,” says Dr. Buti.

Among the causes that are being considered, he adds, the hypothesis with “the most possibilities – but not confirmed, because it is still under investigation, he clarifies – is that, behind it, there is an adenovirus”. It is based on the fact that, especially in the United Kingdom, which is where the most cases have been registered, this pathogen was detected in 75% of these children. “And they have seen that the circulating levels of adenovirus are higher than one or two years ago,” says the spokeswoman for the Spanish Association for Liver Studies .

Children, more exposed after the pandemic

It is then that the specialist questions: “Why has the adenovirus been able to produce this? If finally the causative etiological agent is an adenovirus, perhaps it is because these children –due to the pandemic and the masks, it specifies– have been less exposed to the adenovirus and now (because they are more exposed) it can produce these pictures,” explains the doctor.

But, in addition, he points out that the health authorities are considering other “other factors that can explain it, such as a toxic, a drug or something else in the environment to interact with adenovirus. In this case, I am not talking about anything in particular because it is under investigation, but they think there could be a cofactor“, says the doctor. He takes the opportunity to send a message of caution, but admits that there is concern. In addition, he indicates that it is normal that, as the days have passed, more cases have been reported. “If there is an alert, search and it is found more than when it is not done”, he concludes.