These results indicate that bats, and in particular species of the genus Rhinolophus, constitute the reservoir of the SARS-CoV and SARS-CoV-2 viruses.īat, Rhinolophus affinis. For example, RaTG13, isolated from a bat of the species Rhinolophus affinis collected in China’s Yunan Province, has recently been described as very similar to SARS-CoV-2, with genome sequences identical to 96%. ![]() Since then, many Betacoronaviruses have been discovered, mainly in bats, but also in humans. It is known that bats of the genus Rhinolophus (potentially several cave species) were the reservoir of this virus and that a small carnivore, the palm civet ( Paguma larvata), may have served as an intermediate host between bats and the first human cases. A total of 8,098 cases were recorded, including 774 deaths. ![]() It is an RNA molecule of about 30,000 bases containing 15 genes, including the S gene which codes for a protein located on the surface of the viral envelope (for comparison, our genome is in the form of a double helix of DNA about 3 billion bases in size and contains about 30,000 genes).Ĭomparative genomic analyses have shown that SARS-CoV-2 belongs to the group of Betacoronaviruses and that it is very close to SARS-CoV, responsible for an epidemic of acute pneumonia which appeared in November 2002 in the Chinese province of Guangdong and then spread to 29 countries in 2003. The SARS-CoV-2 genome was rapidly sequenced by Chinese researchers. This raises questions about the link between this COVID-19 epidemic and wildlife. Instead, a molecular dating estimate based on the SARS-CoV-2 genomic sequences indicates an origin in November. But, according to a study conducted at Wuhan Hospital, the very first human case identified did not frequent this market. ![]() In December 2019, 27 of the first 41 people hospitalised (66%) passed through a market located in the heart of Wuhan city in Hubei province. In which animal species did it occur? A bat, a pangolin or another wild species? Where does it come from? From a cave or a forest in the Chinese province of Hubei, or elsewhere? And while the number of scientific articles on this virus is increasing, there are still many grey areas as to its origins. But there have also been a lot of rumours. In the space of a few weeks, we have all learned a lot about COVID-19 and the virus that causes it: SARS-CoV-2.
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