Is the virus a human friend?
Professor Konstantin Severinov: Is it possible to create protection against future viruses in advance
Yuri Medvedev, Rossiyskaya Gazeta
Is the person himself to blame for the appearance of new viruses? Is it true that humanity is just one mutation away from a catastrophic pandemic? Why is covid-19 spreading so rapidly? The correspondent of "RG" talks about this with a microbiologist, professor of the Skolkovo Institute of Science and Technology and Rutgers University (USA) Konstantin Severinov.
There have always been viruses, they have claimed millions of lives, but what we are seeing now, according to many experts, is happening for the first time in the history of mankind. Previously, even the most severe epidemics were local. For example, the "Spanish woman" raged in Europe, but she was not heard of in Asia or America. (In fact, the "Spaniard" covered all continents except Antarctica - VM.) And now an invisible creature has struck the whole world. There are no boundaries for him. Moreover, it is unclear when and how all this will end. How to explain this phenomenon?
Konstantin Severinov: Let me remind you that there are hundreds of millions of times more viruses on our planet than there are stars in the known universe. Viruses are present not only in humans and animals, but also in plants and bacteria. By the way, there is a hypothesis of the famous American scientist, a native of Russia, Evgeny Kunin, that the basis of all life is cells, which also originated from viruses several billion years ago.
Is there anything special happening now in connection with the covid-19 pandemic? People tend to allocate the time in which they live, consider it something exceptional. For example, the inhabitants of Europe considered pestilence as a scourge of God, given to them as punishment for their sins, but history shows that epidemics of smallpox, plague and other infectious diseases occurred with enviable regularity. What is happening now is quite a natural process. Humanity has met with a new virus for itself, and it is rapidly spreading through the population. We can draw an analogy with the situation in which the American Indians found themselves. The greatest damage to them was caused not by the cruelty of the European conquerors, but by the smallpox that they brought there. The local population has never encountered this virus and turned out to be virtually defenseless against infection.
But you must agree that the current epidemic has turned out to be so global for the first time in history...
Konstantin Severinov: Perhaps, although the same "Spaniard" was not a European phenomenon at all, but raged all over the world. The global spread of the virus was "helped" by the First World War, when the movement of people around the planet increased dramatically. The situation is similar with the current pandemic. There is nothing unusual about the virus itself. But the world he got into has really changed. The level of global mobility of people has increased dramatically compared to the past. And the virus moves along with infected people. Hence the high rate of infection. The obvious counteraction measures are to reduce the movement of people and contacts between them. As soon as such measures are introduced, the infection figures are reduced and the situation improves. After all, this virus is much less deadly than many other "old" viruses, such as smallpox or measles. Another question is that quarantine measures violate the lifestyle to which we are all accustomed.
The participants of one TV show, discussing covid, stated how great it would be to live without viruses at all. And they wondered if science could not save us from this scourge once and for all.
Konstantin Severinov: The very task of destroying all viruses on Earth is absurd. We have already said that they exist as long as there is life on our planet. They were before the man appeared here, and they will be after us. Viruses are constantly evolving, exchanging genetic material with each other, as a result, new viruses arise. While their scanty share has been studied and classified, most remain a white spot. But one thing is already clear: from this viral "universe" the proportion of human pathogens is negligible.
It is extremely important to understand that viruses serve as a source of evolutionary innovations for their hosts and in this sense they are "useful". After all, only a small part of the human genome are genes that encode proteins necessary for life, and the lion's share are the "buried" remnants of the DNA of viruses that infected our ancestors. The exact function of most of these remnants is still unknown to science, but something is already clear. For example, mammals have a placenta that allows the fetus to be connected to the mother during pregnancy. It has been established that the protein responsible for its function has a viral origin. That is, the placenta originated in a distant common ancestor of all mammals as a result of infection with a virus.
And if man is the crown of evolution, then he became it largely thanks to viruses.
Recently, the number of new viruses has increased significantly. There are Ebola, Zika, MERS, SARS, COVID-19 viruses and a whole number more. What is the reason? Maybe this is a protective reaction of nature to the offensive of a person who is increasingly interfering in the environment? She's so resistant.
Konstantin Severinov: Our civilization has existed for several thousand years, and viruses were discovered only 130 years ago. But the fact that we did not know about their existence, of course, does not mean that they did not exist. Are there more viruses? It is difficult to say unequivocally, serious research is needed. But it is absolutely certain that the arsenal of tools necessary for the discovery of new viruses is constantly expanding. With the development of genomic technologies, this has become especially simple and fast, and the example of the coronavirus shows this. It took years to detect the AIDS virus, and Covid was dealt with in just a month. So it is difficult to say whether the appearance of new viruses is due to the increased pressure of people on nature or to the achievements of science.
There is undoubtedly such pressure, but it seems to me that it is the increased mobility of people that is the determining factor. The source of covid is considered to be bats that live in Wuhan caves. I think the ancestors of the current Chinese went to these caves for thousands of years and, of course, were infected. But their contacts were local, within the boundaries of their village. And now, in the conditions of global transport, almost all of humanity becomes hostage to an unsuccessful meeting of one person with a mouse from a cave.
One of our well-known doctors has repeatedly stated that the COVID-19 coronavirus is not so dangerous, that in fact we are just one mutation away from a really terrible epidemic, which, as a "Spaniard", will take millions of lives. We are talking about avian flu, the lethality of which is many times higher than that of the coronavirus. Fortunately, so far this virus is transmitted only from animal to human, so it does not spread widely and does not threaten epidemics. But one mutation is enough, which will open the possibility for the transmission of the pathogen from person to person, and the picture will change dramatically. Are we really one step away from a global catastrophe?Konstantin Severinov:
Mutations can really change the properties of the virus. Modern research shows that the second, most dangerous, wave of "Spanish flu" occurred due to the appearance of only a few mutations in the original version of the virus. But making predictions is a thankless task. This doctor is talking about one "scary" mutation or a combination of mutations. But no one knows in advance what this combination should be, and in general, whether it is possible. The lethality of the virus and the rate of its transmission from one person to another, generally speaking, are not related things. It is possible to have a high mortality rate, but it is poorly transmitted, which will limit the scale of the epidemic. In addition, viruses and their various variants compete with each other for their hosts. Therefore, it is not a fact that this "killer", even if it does appear, will be able to win in competition with other, less lethal variants that have spread more widely in the population and caused collective immunity.
What can this global epidemic teach us? Is there any strategy to protect against new attacks that can be worked out? Prepare for it ? Are you already looking for unknown viruses? After all, you said that science was able to deal with covid in a month.
Konstantin Severinov: Alas, it will not work. Suppose you have identified some unknown DNA or RNA in a sample taken from a person. Who does it belong to? Dangerous virus or not? No one will tell in advance. Therefore, it is necessary first to have many patients suffering from some kind of disease, and only then to associate the diagnosis with the presence of unknown DNA. Since there are practically no direct-acting drugs aimed at suppressing viruses, the best way to fight infection is to develop a vaccine. But it cannot be created in advance, work begins only when the virus is identified and its connection with the disease is proven. It won't work any other way. So there can be only one preparation for a meeting with a new dangerous visitor - it is necessary to raise the level of life sciences, medicine, and the healthcare system through priority funding of these areas, training and creating conditions for work. And then the coordinated work of scientists, doctors, epidemiologists and relevant officials will help at the right time to find an answer to the attacks of new viruses in the shortest possible time.
Help "RG"Who is to blame
The army of viruses attacking us is rapidly replenished with new fighters, and they are becoming more diverse. Only in recent years, Ebola, Zika, MERS, SARS, COVID-19 and a number of other viruses have joined it. What is the reason?
According to scientists, the man himself caused the trouble. By his activities, he makes enemies. This is described in an article by an international group of scientists in the journal Royal Society Publishing. After all, we get most infectious diseases from animals that infect humans upon contact. The worse the habitat becomes and the ecology deteriorates, the more likely it is that new aggressive microorganisms will appear.
Man is constantly expanding his spheres of influence, occupying new areas, displacing local animals and forcing them to look for new habitats. Of course, this is the strongest stress for them with all its consequences. It turned out that it is the species that will experience it, fighting for their habitual life, that are carriers of twice as many dangerous viruses as well-off species. Hunting, trade development and urbanization have led to mass migrations, significantly increasing the chances of getting an infection from animals. And of course, the worse the habitat becomes and the ecology deteriorates, the more likely it is that new aggressive microorganisms will appear.
In short, the verdict of the authors of the study is unequivocal: human invasion of wild animal habitats, environmental degradation are the main causes of infectious diseases on a global scale.
MeanwhileGood and bad
The killing power of the virus is stronger than any war. For example, the Spanish flu epidemic in 1918 claimed from 50 to 100 million people, about 200 million died of smallpox in the XX century alone. In a word, it seems that there is no animal more terrible than viruses. This has long been the opinion of most scientists who have studied only pathogens that cause diseases. However, recently science has begun to deal with the whole giant family of viruses, and a whole world has opened up. It turns out that there are good ones among them, and such are the overwhelming majority. For example, bacteriophages, from the Greek "devour". In the world of bacteria, they are the main predators. Without them, we would have had a hard time. If they suddenly disappeared, many populations would grow explosively and overwhelm others. Phages stand guard, do not allow one to dominate at the expense of others. In fact, preserving biodiversity on the planet.
But phages are also used in medicine to destroy bacterial infections. This is especially true now that pathogens have learned to resist antibiotics. In addition, bacteriophages can be precisely tuned to affect certain types of bacteria - unlike antibiotics, which destroy all bacteria indiscriminately.
Today, science is getting more and more evidence that viruses have played a key role in human life. A number of studies show that it is to viruses that mammals owe the ability to live birth, the formation of the nervous system in vertebrates. Moreover, there are theories that viruses may be behind the emergence of DNA.
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