According to some researchers, the causative agent COVID-19 can be derived from the hybrid between the coronaviruses of bats and pangolins. The genome of the virus which affects people, 96% identical with the genome of the virus of bats, but he gets in human cells due to thorn the squirrel, which is typical for a version of this virus from Javanese pangolin. That is, mankind is faced with a chimeric virus, and how it came about remains a mystery.
During the epidemic of coronavirus, scientists have learned about it quite a lot. For example, it became clear that the outbreak began in December when reports emerged about the first hospitalized, and another in November. As the center of origin of the virus, apparently, was not the seafood market in Wuhan, and some other place.
However, as it emerged COVID-19? Genetic analysis causes the disease of the virus SARS-CoV-2 showed that it belongs to the group of before everyone and you have a close relative of the SARS-CoV, the causative agent of atypical pneumonia.
Researchers it is known that the SARS-CoV virus comes from bats Tulip-like horseshoe bats (Rhinolophus). “Transfer link” between them and the people likely to have been small carnivore Himalayan civet cat (Paguma larvata), whose meat is popular in Chinese cuisine, says Science Alert.
Apparently, SARS-CoV-2 also occurred in populations of bats. Some characteristic of these viruses is very similar to him. For example, the genome of the virus RaTG13 isolated from the body of the Asian horseshoe bat (Rhinolophus affinis), coincides with the genome of SARS-CoV-2 to 96%.
According to scientists, bats are a natural reservoir of various coronaviruses. This means that in their bodies of the infection to multiply, almost without causing symptoms. Perhaps this is due to the fact that the immune system of these animals is well adapted to combating coronaviruses.
Meanwhile, some researchers pointed to other suspects – pangolin. So, the genome of the coronavirus, which is characteristic for the Javan pangolin (Manis javanica), is similar to SARS-CoV-2 to 90%. It’s no big similarities. However, the spiky proteins required for penetration into the cell, this virus is 99% similar to that characteristic of SARS-CoV-2.
Thorn protein of the virus RaTG13 matches those of the SARS-CoV-2 is only 77%. This means that the coronavirus pangolin can penetrate into human cells, and coronavirus bat – no.
Thus, a new coronavirus partly coincides with a virus of bats, and partly with viruses pangolin. According to scientists, this may indicate its chimeric origin. In other words, it is a kind of hybrid between the two viruses.
The process of recombination of coronaviruses in nature, already known to scientists. According to them, this mechanism often leads to the emergence of hybrid viruses that can attack a new kind of hosts. However, for this, two coronaviruses must meet in one organism. Where and how this happened in the case of SARS-CoV-2 is still unknown. However, many experts are inclined to think that this is somehow connected with captive growing and eating wild animals.
Meanwhile, in Wuhan, China, where the coronavirus triumphant march around the world began, quarantine measures are gradually weakening. Residents are already allowed to leave their homes, and public transport will resume work soon.
Experts are surprised by the mortality rate from coronavirus in Germany – it still does not exceed 1%, while in Italy it is approaching 10%. Despite the fact that the level of medicine and the age composition of the population in the countries are quite close. There are only two explanations for this oddity.