When did Covid-19 appear?
This cannot be determined with precision. All we know is that the first cases were detected in the Chinese city of Wuhan a year ago, and then the virus spread to Asia, and the world. The World Health Organization says on its website: “We believe that the first cases in Johan date back to early December.”
She added: “But the place where the epidemic was first detected is not necessarily the epicenter of the virus,” explaining that “it is not unlikely that the virus has spread elsewhere without being detected.”
In recent months, researchers in several countries confirmed that there were cases before December 2019, but they were not monitored, based on analyzes of wastewater and blood samples tests conducted later.
But this information is “not yet confirmed,” said Etienne Simone-Laurier, in charge of the Virus Evolution Unit at the Pasteur Institute in Paris.
To develop the genetic map of the virus, researchers rely on genetics. The Health Organization says that these analyzes “allow to better understand the modes of transmission of infection, especially the way the virus evolved over time and how several foci can be related to each other.”
The WHO formed an international team to return to the roots of the virus. The team must study the suspicious animals and the way in which the infection was transmitted to the first infected.
How was the virus born?
Scientists are unanimously agreed that the virus was transmitted to humans from an animal. “The mysterious question is what prompted the virus to pass from animal to human,” Simon-Laurier told AFP.
He added that it is likely that bats are behind the spread of Covid-19, “as it is the main reservoir for corona viruses.” It remains to discover the intermediate host, since it is unlikely that Covid-19 was transmitted directly from bats to humans.
He suggested that the pangolin (anteater) was the intermediate host based on genetic analysis, but this is not yet certain.
The mission of the WHO aims to clarify this point by studying other animals that were sold in the Hunan Market in the city of Wuhan, where the first cases appeared.
Simon-Laurier added: “It is permissible for the medium to be an animal that captures the virus in a way that is very close to the way a human catches it.” The catcher is nothing but the “ICE2” protein that the virus uses to infiltrate cells.
However, mink and mongoose are very close to humans, and this does not apply to other animals.
But this does not mean that we have found a clear answer. The Health Organization says that “the spread of a new virus among humans is one of the biggest riddles that an epidemiologist can decipher.” “It is a search for clues,” adds Simon-Laurier. “We have not yet cracked the code for the Ebola epidemic.”
How about the lab?
In the spring, US President Donald Trump confirmed, against a backdrop of diplomatic tension, that the virus may have accidentally emerged from a specialized laboratory in Wuhan. China rejected the accusations, but this issue is still returning to the fore.
And recently, virologist Etienne Ducrule announced, on the website of the French National Center for Scientific Research: “As long as we do not discover the intermediate host, the hypothesis of an accidental accident in a laboratory cannot be excluded.”
In turn, Simon-Laurier says: “We are compelled to present this scenario even if it is practically excluded because it requires great efforts to cover up and spread lies.”
On the other hand, the scientific community excludes another hypothesis waved by believers in the conspiracy theory that the new Corona virus was installed in a laboratory.
Simon-Laurier explains that “all the elements of the virus genome were detected in nature mainly in the corona viruses found in bats. Therefore, there are no indications that it was man-made.”
What is the time limit granted to the WHO team?
After sending an expeditionary team in July, the WHO hopes that it will be able “soon” to visit China, as I reported on November 23.
But science is not the only consideration, and diplomatic considerations also enter this issue.
Washington accuses Beijing of hiding the affairs of the WHO by yielding to the will of the Chinese authorities. And member states of the World Health Organization suspect Beijing is putting up obstacles in this regard, but they are less critical than the United States.
And on Monday, WHO Director-General Tedros Adhanom Ghebreyesus declared, “We want to know the source and we will do everything possible to find out.” He emphasized that “there is nothing to hide.”
He said: “The health organization’s position is very clear: we must know the source of this virus, because that would help us avoid future epidemics.”
He explained that it is a “technical issue”, denouncing that some have “politicized” it.
Why is knowing the source of the virus important?
The Health Organization declared that “uncovering the cause of an epidemic is essential to avoid the spread of other viruses among humans.”
Simon-Laurier says the goal is “to take measures to avoid the emergence of new, more advanced types of Coronavirus.”
These measures aim “to change our methods of contact with animals that may cause the transmission of new viruses,” by prohibiting the breeding of certain species, for example.
During the outbreak of severe acute respiratory syndrome in 2002, the ban on eating certain types of animals and the suspension of their breeding contributed to preventing the transmission of the virus to humans.