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Although many animals carry dangerous viruses, they are usually not transmitted to humans - to our happiness.

"In most cases, there is a species barrier that the virus cannot overcome," says Professor Andrew Easton of the School of Biomedical Sciences at Vorik University.

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But sometimes, if a person has an immunodeficiency or there is some other important factor that will open the virus to the body, it is possible to get an uncharacteristic sporadic case (infection. - Ed.), "- says the scientist.

The danger often begins with an unusual mutation.

"There will usually be some changes that will allow him to grow into a new host," Professor Easton explains.In these rare cases, when the coronavirus is transmitted to humans, the situation can be very serious.

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It is worth noting that not all coronaviruses are very dangerous - people are constantly faced with less harmful types. But it is precisely those that are transmitted from one species to another that pose the greatest danger.

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