The coronavirus can only infect mammals, but not fish, birds, or reptiles. This conclusion was reached by molecular biologists who studied the structure of key proteins that SARS-CoV-2 uses to penetrate cells.
Proteins of 215 species of fish, reptiles, birds and mammals were analyzed, according to an article in the bioRxiv electronic library.
“These calculations confirmed that SARS-CoV-2 can enter the cells of a wide range of mammals, but they cast doubt on the fact that it can infect fish, reptiles and birds,” wrote scientists from University College London (UK) and their colleagues from India and Malaysia.
The SARS-CoV-2 coronavirus penetrates human and other mammalian lung cells using ACE2 protein molecules. It covers certain types of alveolar cells. These outgrowths play an important role in the life of SARS, the pathogen of SARS and a close relative of the new type of coronavirus.
The gene encoding this protein has several different variations in the genomes of different mammals. These variations do not prevent infection of cats, ferrets and monkeys, but significantly reduce the likelihood of the virus entering the body of mice and rats.
As the head of Rospotrebnadzor Anna Popova said earlier on Saturday, there are currently no cases of repeated infection with the coronavirus in Russia. The day before, she explained that the rejection of restrictive measures for coronavirus will be gradual and depend on the epidemiological situation in the regions.
It is also recorded Somewhere in China, a bat flits across the sky, leaving a trace of coronavirus in its droppings, which fall to the forest floor. A wild animal, possibly a pangolin snuffling for insects among the leaves, picks up the infection from the excrement.
The novel virus circulates in wildlife. Eventually an infected animal is captured, and a person somehow catches the disease, then passes it on to workers at a wildlife market. A global outbreak is born.
Scientists are attempting to prove the truth of this scenario as they work to find wild animals harbouring the virus. Finding the sequence of events is “a bit of a detective story”, says Prof Andrew Cunningham of Zoological Society London (ZSL). A range of wild animal species could be the host, he says, in particular bats, which harbour a large number of different coronaviruses.
In total, as of may 2, 124,054 cases of coronavirus were registered in Russia in 85 regions. 1222 patients died and 15,013 people recovered.