What we (don't) know about the origins of the coronavirus

Sars-Cov-2 is most likely a natural virus, but it is not excluded that it may have escaped by mistake or accident from a laboratory. Will we ever know how it went?

(photo: Getty Images) The annual general assembly of the World Health Organization (WHO) revolved around the Sars-Cov-2 pandemic and the ongoing investigation to find out the origins of the coronavirus. Research that, from the indiscretions on the US intelligence report that raises strong suspicions about an accident at the Wuhan virology laboratory, has become more urgent, with several members pushing for it to go deeper, while China asks to expand the audience of states that could have been the true birthplace of the coronavirus.

Here are the hot spots of the discussion.

Sars-Cov-2: natural or artificial?

The position of most experts on the subject has not changed compared to what has already been said in the last year: the analysis of the Sars-Cov-2 genome has not found evident and irrefutable signs of modifications made by the human being, but rather there would be a high similarity (96%) with the coronavirus genome of the Ratg13 bats, which however may not be the closest relative, which still remains unknown.

A natural origin, in short, still seems to be the more likely, also because it wouldn't be certainly the first case of spillover (just think of the origin of the coronaviruses cousins ​​of Sars and Mers, jumped from animals to humans). In any case, any doubt is legitimate and the scientific community is open to debate and sifting through new hypotheses and argued opinions.

Sars-Cov-2: escape from the laboratory?

Even admitting that Sars-Cov-2 is a natural virus, this - some argue - does not exclude that it could not have spread precisely from a laboratory like the one in Wuhan where he was studying. Those who advance this conjecture (such it is at the moment) believe that a virus escape from the laboratory may have occurred through one of the researchers, who became infected while collecting samples in the field or working with the virus. However, there is no evidence to confirm this possibility for the moment.

Does Sars-Cov-2 come from a mine in China? Researchers from the laboratory are known to Wuhan between 2012 and 2015 were called to collect samples inside a mine where bats also lived, after several miners fell ill with an unknown respiratory syndrome. The documentation provided by the Chinese laboratory to the WHO speaks of nearly 300 coronaviruses detected, but not a dozen have been able to completely or partially isolate the genomes, and only 3 would have been cultured in the laboratory.

None would match Sars-Cov-2, as declared by the Chinese. WHO experts do not doubt the numbers presented, which are compatible with the numerous technical difficulties that exist. On the identity of isolated viruses, there are no elements to accuse China of lying and hiding information from the WHO, the possibility can always be there.

Why is the intermediate animal not found?

For those who are not convinced of the natural origin of the virus or even of a laboratory accident, it is suspected that the intermediate animal between the bat and the human being is not found. However, scientists remember that it is not really that easy to trace the origins of a pandemic virus and that research can take years and it is not certain that it will be resolved: it is necessary to identify the most likely animal hosts (susceptible to infections and close contact with human beings), identify any outbreaks, recover an intact viral genome before a sick animal dies or eliminates the infection. So for Sars it took 14 years of investigations, while still today the genome of the Ebola virus responsible for the largest epidemic in the world, that between 2013 and 2016, has not been isolated in an animal.

Why did the pandemic break out in Wuhan, where there is a laboratory that studies coronavirus?

Lovers of conspiracy may see a coincidence that is too strange to be just such a coincidence. However, as virologist Vincent Munster del Nih points out in Nature, many microbiology laboratories specialize on the viruses that surround them: in Latin America there are centers focused on the pathogen of dengue fever, in Africa on that of hemorrhagic fever, in Asia ( therefore also in China) are specialized on influenza viruses and coronaviruses. Coronaviruses in the Wuhan region are endemic, and given that the area is huge and heavily populated, and contains an airport, train stations, even wildlife markets, the chances of a potentially dangerous virus spreading rapidly are higher than in other places on the planet.

Why is Sars-Cov-2 transmitted so efficiently between people?

The containment measures put in place by states to stem the spread of the coronavirus have perhaps altered the perception of public opinion regarding the ability of Sars-Cov-2 to be transmitted from person to person. The measures were deemed necessary to possibly avert something worse (practically nothing was known about the new coronavirus) and to prevent the collapse of health systems. But, especially in the early stages of the epidemic (then the variants changed things a bit), the virus's ability to infect people was not overwhelming, and it wasn't even specific given that it can infect many other mammals. This is why the claim that it is designed specifically to target humans, for scientists, has no basis.


Social Networks - 2 hours ago

China blocked several profiles on social networks related to cryptocurrencies

adsJSCode ("nativeADV1", [[2,1]], "true", "1", "native", "read-more", "1"); Health - 20 hours ago

The trial against Adriano Panzironi is in full swing

adsJSCode ("nativeADV2", [[2,1]], "true", "2", "native "," read-more "," 2 "); Medicine - 22 hours ago

Do white zone criteria risk reducing tracking?

Topics

China Coronavirus Health globalData.fldTopic = "China, Coronavirus, Health"

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.