New virus in China: everything we know (and what we don’t) about the 35 cases that have just been detected in the Asian giant

35 cases of an unknown disease in central China have raised alarm bells internationally. In principle, the initial analyzes invite calm, but much is still known about this small outbreak. 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 identifying a new virus of animal origin of the Henipavirus type that had infected 35 people in two provinces located in eastern China, Henan and Shandong. None of them serious; however, it has caught the attention of half the world.

What symptoms does it cause? From what is said in the report, the main symptoms are fever (it has occurred in 100% of the patients), fatigue (54%), cough (50%), anorexia (50%), myalgia (46%), nausea (38%), headache (35%), and vomiting (35%). Associated with these, cases of thrombocytopenia (35%), leukopenia (54%) and impaired liver function (35%) or kidney function (8%) have also been found.

The fact that no serious cases have been found reassures researchers because other viruses in the same family do have a greater impact on health. The Hendra virus (the best known of its “first cousins”) causes infections in humans ranging from asymptomatic to acute respiratory infections and severe encephalitis, with an estimated fatality rate of between 40 and 75% that “can vary depending on local capacities for epidemiological research and clinical management”.

How is it transmitted? “The 35 patients from China did not have close contact with each other or a common exposure history, and contact tracing did not show any viral transmission between contacts,” said Jen-hsiang, Deputy Director General of the Taiwan CDC. friends and family, suggesting that human infections could be sporadic.

However, although these are the first indications, there is no reliable information about the virus. It is not about generating alarm, but it is about the epidemiological surveillance systems being alert. Only now are the first genomic studies being carried out and epidemiological controls are being reinforced to closely monitor the evolution of the disease (and the possible outbreak).

Where did it come from? That was the question the researchers asked themselves, and to answer it they conducted “a serological survey of domestic animals detected seropositivity in goats (3 of 168 [2 %]) and dogs (4 of 79 [5 %])”. Beyond that, “among the 25 species of small wild animals surveyed”, “it was detected predominantly in shrews (71 of 262 [27 %])”: something “that suggests that the shrew may be a natural reservoir” of the virus; but that contrasts with other viruses of the same family that usually have bats as reservoirs.

Are there reasons to be alarmed? On the one hand, no, of course. Strange outbreaks appear in the hundreds every year and most of them go nowhere and the diseases of recent years (COVID, childhood hepatitis, monkey pox, etc…) are making us especially sensitive to this kind of news. On the other hand, we know that we have to be vigilant: going from a local outbreak to a global epidemic has never been easier than it is now.