As cases continue to be identified in the northern hemisphere, research into the origins of this mysterious childhood hepatitis continues. In the last hours, as we confirmed, about half of the patients they tested positive In adenoviruses, the adenovirus 41 hypothesis gained strength. But the parts still do not fit. Why do we suspect him? Why does something seem to be missing?

What are human adenoviruses? Adenoviruses are one of the most common pathogens in humans and we often find them in respiratory, eye, gastrointestinal, urinary diseases and many more. To give us an idea, we have now identified 103 subtypes of human adenoviruses. This means that there is a wide variety of diseases and symptoms associated with adenoviruses, and that the potential routes of infection are very diverse (by air, contact, and even water).

However, he is a strange suspect. When we talk about adenoviruses, we are not talking about rare viruses that appear out of nowhere. Rather, they are a family of pathogens that have been studied over and over, and so although there are some signs to think about them, experts show their bewilderment and insist on caution.

Why do we suspect adenovirus 41? As announced by health officials, 74 (out of 169 patients) studied so far have tested positive for different adenoviruses, of which 18 have tested positive for adenovirus 41 specifically. It’s inconclusive and doesn’t fit very well, but it’s a reasonable hypothesis.

Serotype 41 of adenovirus type F is behind 1.2% to 15% of pediatric gastroenteritis. In other words, it creates a picture of fever, vomiting and diarrhea. A picture that can be serious and require hospitalization, but more often associated with severe diarrhea (not liver problems). However, some cases of hepatitis have been documented in immunocompromised children, but nothing like what we’ve seen.

Like this, as described Meera Chand, director of infections revealed this Monday at the UK Health Security Agency (UKHSA), is working on the hypothesis that there is a “cofactor” that causes “normal adenovirus infections to be more serious or trigger more serious immunopathology”. in young children.

Cofactor? Yes, the main idea of ​​the study today is that if it’s adenovirus 41, it must be a cofactor, something else that amplifies its effects. This cofactor can be almost anything: from an increase in immunological susceptibility after the pandemic to co-infection (19 cases tested positive for adenovirus and SARS-CoV-2) or a cross-effect with some environmental agent, drug or toxicant.

still working. We are only in the early stages of the investigation and it is difficult to find clear commonalities apart from the very obvious things like the vast majority of children have not been vaccinated against covid-19. Thus, apart from adenovirus, not thrown We are dealing with a new unidentified subtype of adenovirus, the effects of a novel coronavirus variant or another virus that we have not yet identified.

Image | HCM