35 cases of unknown disease in central China have raised international alarm bells. In principle, the first analyzes invite to calm down, but a lot is still known about this small epidemic. We have compiled all the information that scientists and authorities have put on the table.

What happened? Just a few days ago, on August 4, the New England Journal of Medicine published a report describing a novel animal-derived virus, type Henipavirus, that has infected 35 people in two eastern China provinces, Henan and Shandong. None of them are serious; however, it has caught the attention of half the world.

What symptoms does it cause? According to the report, the main symptoms were fever (seen in 100% of patients), fatigue (54%), cough (50%), anorexia (50%), myalgia (46%), nausea. (38%), headache (35%), and vomiting (35%). Depending on these, cases of thrombocytopenia (35%), leukopenia (54%), and liver dysfunction (35%) or kidney function (8%) were also found.

The absence of a serious case reassures researchers because other viruses in the same family have a greater impact on health. Hendra virus (best known among its “first cousins”) causes infections in humans ranging from asymptomatic to acute respiratory infections and severe encephalitis, with an estimated mortality rate of 40 to 75% “which can vary depending on local capacities for epidemiological diseases”. research and clinical management”.

How is it found? “The 35 patients from China had no close contact with each other or a shared history of exposure, and contact tracing did not show any viral transmission between contacts,” said Jen-hsiang, Deputy Director General of Taiwan CDC. friends and family suggest that human infections may be sporadic.

However, although these are the first symptoms, there is no reliable information about the virus. It’s not about generating alarms, it’s about keeping epidemiological surveillance systems on the alert. But now the first genomic studies are being conducted and epidemiological controls are being strengthened to closely monitor the evolution (and possible outbreak) of the disease.

Where did it come from? That’s the question the researchers asked themselves, and to answer it, “a serological study of pets detected seropositivity in goats (3 out of 168 people). [2 %]) and dogs (4 / 79) [5 %])”. Furthermore, “among the 25 small wild animal species studied”, “it was detected predominantly in shrews (71 out of 262). [27 %])”: something that “suggests that the shrew may be a natural reservoir of the virus,” but this contrasts with other viruses from the same family that often have bats as reservoirs.

Are there reasons to be worried? On the one hand, of course not. Hundreds of strange outbreaks occur each year, many of which go nowhere, and diseases of recent years (COVID, childhood hepatitis, monkeypox, etc…) make us particularly susceptible to such news. On the other hand, we know we need to be vigilant: moving from a local epidemic to a global one has never been easier.