"From the bat to the anteater" .. Why do deadly viruses originate in China?

"It's SARS and it's back again," writes Li Wenliang, a Chinese ophthalmologist who works at Wuhan Central Hospital, through a group that communicates between city doctors themselves in the famous Chinese application "Wei Chat." Some comrades take the initiative from other hospitals to say that they have experienced similar cases, more frequent than usual, including severe pneumonia, which quickly develops requiring intensive care. We are now in late December of 2019, the uncertainty is controlling the atmosphere little by little and the tension is increasing, but within a few days it will become clear that he is not "SARS", but rather a new killer.

Whistle blower

To understand the matter, we can go back together to December 2002, before that point in our history the world was dealing with coronaviruses that infect the respiratory system as a benign thing that causes humans in the common cold, which requires a week or less in order to She is on her way, but that was before it turned into a medical disaster. Here we are talking about severe acute respiratory syndrome (SARS), which appeared in northern China, and exceeded its borders within only three weeks to reach eight thousand A person around the world, and causes the death of more than eight hundred of them.

But most fearful for that group of Chinese doctors was that SARS infected and killed many healthcare professionals who were in direct contact with the patients, and therefore Wenliang cared to warn his colleagues, but unfortunately he was one of the “corona” victims where he passed away on the seventh From February, this was after Chinese security forces detained him for promoting rumors. Wenliang was universally called the "Whistleblower", the man who fired the first warning signal (2).

Both "SARS" and "new corona" appeared in China, and if you expand your view a little, you will find that sub-Saharan Africa also suffers - at intervals - from the emergence of entirely new epidemics, take Ebola for example several years ago, which leads us to an important question Indeed, it is the cause of global public tension toward China in particular: Why do new epidemics continue to appear in such areas in particular? Is it because of the climate, the behavior of people, or something else? 

Kings of Metamorphosis

Well, to understand how deep it is, let's start with coronaviruses, "SARS" or "novel corona," for example. They are very simple creatures, just made up of a shell surrounding a DNA that carries a code that enables the virus to copy itself into living cells, when it enters " "Corona emerging" through the nose of one of the patients, it binds to the receptors outside the cells of the airway up to the lung, that sticking occurs through those Spike Protein (3) on the surface (in a way similar to the lock and the key), pulls those receptors into the cell and there His work begins by forcing its system to manufacture its parts, then to reinstall them Parts again to make new viruses, hundreds of them and possibly thousands exiting the cell, breaking them down, then spreading into other cells in the same way.

In a civet cat, a graceful night animal that lives mainly in tropical Asia and Africa, the same thing happens, and when it is infected with a coronavirus, it multiplies in the same way, but during the formation of these new viruses in the civet cat's pulmonary cells it may happen that they change The composition of some parts of the virus, and due to the simplicity of its structure, a slight mutation in its DNA, which is normal, can make a big change. Usually, this change causes the virus to die, and it may not be effective, but in rare cases, it happens that the coronal stools of the virus change in a way that allows them to infect another organism other than this cat.

In normal cases, the virus of the civet cat may transfer to humans and then pass through our bodies without a trace, because it cannot bind to any type of receptor in the cells of our respiratory tract, but in very rare and special cases the coronary emergence of the virus can mutate so that it can bind to the cells Human pulmonary, here the rules of the game change, the virus has become able to tamper with human bodies. The first transmission from an animal to a person is usually only one trip, meaning that this person is not able to transmit the disease to others, but in a few cases the virus can pass between people. 

Corona's extended family

We know that there are only seven types of coronavirus that infect humans, four of which infect us with 10-15% of the usual cold, and three of them are serious, the three of which have been caused by similar jumps (4), "SARS" jumped to humans from the civet cat, and " "MERS", or severe acute respiratory syndrome in the Middle East, jumped from the camels in Saudi Arabia in 2014, and scientists were able to track the genomes of the novel corona to bats, but we now know another organism that may have been an intermediate family that carried this virus to us, it is The scaly anteater.

There are in fact thousands of types of coronaviruses like the "Corona emerging", whose origins extend to bats and birds, and branch into four groups in a wide range of the animal world, you may be surprised when we say that "SARS" and "MERS" were not only coronaviruses Which have crossed from animals to humans during the past two decades before the "newborn corona", there are two additional types (5) called HCoV-OC43 and HCoV-229E that also crossed into humans, but they are benign, causing common cold.

It is the course of the natural development of things, after the changes go ahead because they are not beneficial or harmful to the object, but some will remain because the environment allows its existence and pushes it to prosper. Therefore, after "SARS" and "MERS", as dangerous viruses, it was expected that a similar leap would take place, but more seriously, it is only the usual probability theory that it plays its simplest roles. This is what prompted Bill Gates (6), and many virologists and epidemiologists in fact, but you do not hear their voices much, to warn that the world is not ready enough for a virus that carries the ideal characteristics of spread and infection and has the ability to achieve an estimated number of deaths estimated at 30 million people around the world Only in less than one year.

There are, in fact, many serious viral diseases of animal origin (7), for example, the Ebola virus disease was a typical case of the transmission of a deadly virus from the fruit bats from the species "Petropodidaihi" to humans, the disease began to appear in 1976 in the two regions of Nizara In Sudan and Yambuku, Democratic Republic of the Congo, near a river called Ebola. HIV is also an animal disease that originated in humans from the chimpanzee, but now it has turned into a separate human disease, and it is believed that the Spanish flu that appeared in 1918 and killed about 50 million people was also of animal origin, in fact, most types of flu that We know it was coming from birds or animals that were domesticated by humans.

Snakes in cages

Well, the foregoing means that the environments in which animals and humans meet with a degree of intensity and adhesion give more possibilities for an effective jump for a virus, and here the animal markets appear, but in China in particular, it exceeds the natural limit, you can find a large number of animals that are sold For the purpose of eating, unlike usual, turtles, bats, scallop ants, cats, dogs, snakes, species of insects, etc., this gives a greater chance than usual in the case of birds and cows, for example, which also remains a threat, to infection with new types of viruses.

The story of the Chinese people begins with wildlife in the sixties and seventies of the last century, while the famine (8) killed hundreds of millions of people, the Chinese government allowed them to trade in animals of all kinds, while people were searching for any way to satisfy their hunger, and here the wildlife appeared with all that It contains animals. After several years, a new type of simple trade in the wild emerged that helped many people overcome hunger. Here, the Chinese government supported this trend through several laws, including the “Wildlife Protection Law” (9) in the 1980s. 

These laws opened the door for wildlife trade to move from simple household attempts to a massive market of 150-200 billion yuan, especially since the new laws have always protected those who want to bring new animals to the market, and they have opened the door geographically for more activity, This was rooted in the Chinese people's culture to some degree. Although unusual foods are often only present in the wealthy classes, they have made it possible to find spinners in all markets next to bears, crocodiles, peacocks, mice, and ostriches with various types of ducks.

This increases the chances of a virus passing from one animal to another or to humans. There are hundreds of thousands of viruses roaming the animal world, and one of them can mutate in such a way that it is able to infect humans who are also roaming around here or there. This happened before and will happen in the future. But, although the idea of ​​trading in various animals is a major reason for the emergence of this type of virus in China, it does not explain it completely, because there are other additional reasons of the same importance, but deeper.

Stuck on the equator

For example, we can consider the number of those who moved to urban life in Southeast Asia and Africa during the first decade of the current century, it is 200 million people (10), we are talking here about two countries the size of Egypt, and the transition to urban life means that the state removes vast areas of forests, What brings people closer to animals that the small area of ​​the forest has forced close to crowding with humans?

Researchers (11) from Stanford University have already indicated recently that Uganda, for example, is a model for this situation, because the expansion of citizens in deforestation in order to build homes and cultivate new lands increased the density of primates in the vicinity of their lands and homes, which raised In turn, it is possible for viruses to pass from these primates to them, even as they take the necessary measures to prevent viral leaps like that.

As for Christine Johnson, a professor at the College of Veterinary Medicine at the University of California, she says in a statistical study issued (12) only a few days ago that if you decide to track the proportions of human-borne viruses that affect humans, you will find a clear pattern that expresses the distance between you and the animal. Which we have domesticated, followed by those in our surroundings such as bats or rodents, followed by those that are unjustly hunted by some. The matter is simple, the closer the animal is to you, the closer the danger is.

On the other hand, this severe environmental disorder may cause severe damage. For example, a study issued (13) in the publications of the National Academy of Sciences several years ago showed that there is a possible threat to the health of citizens in several regions of the continent of Africa due to diseases transmitted by rodents. This happened because of the spread of rodents in several new urban areas because the removal of Forests wiped out the animals that feed on these rodents, which allowed them to breed more, and thus increased the chance of disease transmission to humans.

In addition, these tropical regions are usually poor, which means that the livestock and birds raised by the people there will receive dilapidated medical and nutritional care, which opens the door for more diseases and consequently their transmission to humans, especially since these areas depend mainly on subsistence cultivation. That is, the type of cultivation that is concerned solely with the production of food that satisfies only the members of a family, which means that any slight disorder can cause major problems due to the lack of stocks of food for humans or animals.

Weapons, germs and steel

In fact, if you meditate a little, you will find that our entire history is also a history of this type of bacterial or viral leap from animals to humans, and whenever the contention appears clear between us, deadly diseases appear again, in his book “Weapons, Germs and Steel,” Jared Diamond believes that centuries are long From coexistence with domesticated animals in the Fertile Crescent region and its European and Asian surroundings, the cause of the transmission of many deadly diseases from animals to humans has caused very severe tragedies throughout our history.

But when the Europeans decided to cross into the Americas, that long history was a soldier in their ranks. Over time, they developed immunity to some of the more severe types of such diseases as smallpox. When they first met the indigenous Americans of the Americas, they transmitted these diseases to them, smallpox for example, so they exterminated them in a way Almost completely, it suffices you to know that this was one of the main reasons at the end of the Inca civilization in South America, where 90% of the population of that region died after the Spanish occupation, they are 18 million people!

Of course, "new corona" will greatly affect the nature of our relationship with all animals over the coming decades, and this change that may happen may help us to avoid more serious future pandemics, or perhaps not, since we have many previous experiences with similar epidemics that were supposed to be a severe warning, But no one cared, and the world continued to build its war and political arsenals with all the enthusiasm it could see.

But the equation is simple, yes, we humans have enough intelligence to permeate all parts of this planet and impose our control over it, in fact we are able to build enough technology to do what we literally want, but the wildlife on this planet possesses a secret weapon in return, which is thousands of types of viruses Which can at any moment jump from a passing mouse or chimpanzee on a tree to someone, causing a pandemic similar to the "emerging corona", or perhaps stronger, who knows?