Since the start of the Covid-19 pandemic, several theories have been established by experts regarding the origin of the virus. Two hypotheses stood out, namely that of the Huanan seafood market in the city of Wuhan, and that of creation in the laboratory.
Recently, three new studies have been published, each providing evidence supporting Huanan’s market theory. None of these studies, however, has yet been peer-reviewed. Nevertheless, if this theory turns out to be true, the original hypothesis concerning transmission to humans would therefore be correct.
The fact that Covid-19 was first reported in Wuhan, which is the site of a major virology institute, has inspired several theories. Among the most widespread, there is for example the hypothesis that says that SARS-CoV-2 would be a biological weapon released accidentally.
During a study whose article was posted online during the weekend of February 26, researchers analyzed the places of residence and work of the first people infected with Covid-19 in 2019. They found that the first cases were located near the western part of Huanan market. It is in this part that most of the species capable of transmitting the virus were sold. The scientists also looked at a larger group of people infected in early 2020. They then observed that the spread seemed to be following a pattern that one would expect to see if transmission to humans had started in that year. Marlet.
On the other hand, another study that analyzed the genetics of early SARS CoV-2 viral lineages (lineages A and B) hypothesizes the existence of at least two distinct cross-species transmission events. Lineage B was found in people associated with the Huanan market while lineage A is closer to the viruses found in bats Rhinolophus. However, the first people infected with line A are said to have recently stayed near the Huanan market.
Professor Michael Worobey of the University of Arizona, who was involved in two of the three studies, said the results support the hypothesis that the pandemic started in the Huanan market.
A team of researchers from the Chinese Center for Disease Control and Prevention also claims to have detected SARS-CoV-2 on several surfaces and in the sewers of the Huanan market after it closed. However, the virus was not found on any of the animals sold on the premises, which would have been irrefutable proof.
Currently, the origins of Covid-19 are so politicized that it is difficult to convince some people despite the evidence. However, scientists have already indicated that the tracing process will take time. In addition, the closure of the market and the removal of most of the animals that were sold there before the arrival of the researchers reduced the chances of finding a non-human host.