The coronavirus has affected our lives. For almost a year now, the coronavirus pandemic has affected us in everything we do. Schools are closing, people are working from home, hospitals are full, and so on.
Who among us would have thought last year that face masks and respirators would become part of our lives? Probably nobody. But where did it all start? Where did the coronavirus come from in the world and how?
In December 2019, in the Chinese city of Wuhan in the province of Hubei, several patients were observed with an unknown disease, manifested by high temperature, muscle pain, respiratory problems, and lung failure, no one knew that humanity was on the verge of a new pandemic.
Patients were mostly related to the local wet market where live exotic animals or their products were sold. The animals on the market lived in considerably cramped conditions and in close contact with humans, which created an ideal environment for the spread of pathogens.
Experts had a strong suspicion that patients had been affected by a viral disease because of the SARS epidemic, because
in China in 2002-2003, caused by a coronavirus, arose under similar conditions.
Shortly afterward, it was proven by molecular genetic methods that patients became infected with a new coronavirus, which they later named SARS-CoV-2. The composition of the entire viral genome was published as early as January 2020, ie only a few weeks after the first identified patient. This paved the way for the development of a diagnostic test.
The new coronavirus triggered the Covid-19 epidemic, which spread rapidly from China to the rest of the world, with the WHO declaring it a pandemic on 11 March 2020.
Where does the new coronavirus come from? To answer this question, we must first know some of its properties. Each virus, upon contact with a cell, binds a portion of its surface protein to a specific cell receptor. In the case of coronaviruses, it is the S protein that contains the binding site for binding to the cell. SARS-CoV-2 has a unique site, with six key amino acids playing an important role. And the virus has yet another unique place.
None of the hitherto known coronaviruses has an additional four new amino acids inserted into the S protein. This creates a site recognized by the cellular enzyme furin protease, which, by cleaving the S protein, causes the virus to be highly infectious and increases its pathogenic effects. Thus, when searching for the origin of a new coronavirus, we must look for a virus that has these unique properties.
Despite the fact that a new coronavirus originated in China, it has so far managed to avoid a major epidemic. The reason is the strict management of covid, which would be unthinkable in states emphasizing the personal freedoms of the population.
Only a few recorded cases of the new virus were enough, and the city immediately announced widespread testing. Tens of thousands of people tested themselves over the weekend.