Is the coronavirus exhaled, as Dr. Myasnikov says? Or is it something else entirely?

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Is the coronavirus exhaled, as Dr. Myasnikov says? Or is it something else entirely?
Is the coronavirus exhaled, as Dr. Myasnikov says? Or is it something else entirely?
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Alexander Myasnikov, head of the Information Center for Monitoring the Situation with Coronavirus, said that "the virus seems to be filtered through our immune forces, every time it enters another organism, it goes a little weakened." In this regard, he expects the wave of infection to retreat "by itself." However, a number of scientific studies - and the experience of the Spanish flu pandemic - point to a different, less benign scenario. Let's try to figure out what science thinks about a certain decline in the number of infected in Russia: why it is going on and when the situation can turn back.

Doctor Myasnikov

Is the virus “how would it be filtered”? Does it really show signs of weakening as it goes from person to person?

Alexander Myasnikov is an experienced cardiologist and general practitioner, once he was also the head physician of the Kremlin hospital, and even now occupies not the last place in the national healthcare. In this regard, his opinion evokes the natural confidence of the population. And it sounds logical:

“The virus is, as it were, filtered through our immune forces and, fighting against them, loses its former power. That is, every time, getting into the next organism, a little weakened one goes further. The wave is growing, but in a month and a half it begins to recede by itself - the more people are infected, the sooner viruses lose their strength, the ability to infect and kill … What we see today is the wave subsiding, the overwhelming number of cases are asymptomatic or with minimal symptoms. Everything is exhausted. Ate the virus, sucked our blood and fell off. Let's hope for a long time. But in any case, if the mutation does not occur, then he will not do a big trouble (unless he is again appointed a "villain" by the media)."

How the experience of the United States and other countries casts doubt on Myasnikov's version

What prevents you from believing it? Let's try to imagine that Dr. Myasnikov is right and the virus “seems to be filtered through our immune forces”, “fizzling out” with each new person infected with it. For example, the epidemic began with a hundred (a conditional figure) who arrived in the country: for example, to Italy or the United States from China. They infected two hundred others ("second" infection), those - four hundred more (third). The tenth "generation of infection" (let's call it that) will cover more than one hundred thousand people, and the twentieth - more than a million.

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This is not just a theory: this is guaranteed to happen in the same States, where only 1.78 million people were infected with the coronavirus. It turns out that even if more than a hundred infected initially arrived there, then he made about two dozen "transitions" to the next organism.

And now let's take Russia, in which the wave of coronavirus "subsides" due to, according to Myasnikov, such transitions. We have identified almost five times fewer patients than in the United States. Maybe they test more in the States?

But as of May 27, 15, 2 million tests were done there, and in Russia - 9, 7 million. It turns out that more tests were done per capita in Russia than overseas. At the same time, only 3, 9% of those tested in our country turned out to be covid-positive, and in the USA there were 11, 1%. It is easy to see that in the States the number of patients per capita simply must be much higher than ours.

But it follows from this that the number of transitions from body to body in coronavirus was much higher in the United States, and not in Russia.That is, in the States, he must "fizzle out" much more.

And if the virus is “weakened”, then the likelihood of severe symptoms should be lower, Myasnikov says. About our country, he writes: "the overwhelming number of cases are asymptomatic or with minimal symptoms." Since there are more "transitions" from organism to organism overseas, then the symptoms there should be easier than ours.

Alas, in practice in the United States there are already over a hundred thousand deaths. The mortality rate of the coronavirus there looks much higher than ours. However, exactly what it looks like - we have already written why this is not so in practice. But even with this in mind - in the United States there are no signs of an easier course of the disease.

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From all this it follows that there are no signs of a decrease in the lethality of the virus during the transition from person to person. Back in January, at the very beginning of the epidemic, we wrote that over time, all new viruses infecting our species lose the bulk of their lethality. But this time is measured in many years, and often in centuries. It is impossible to seriously say that this can happen in months. There are simply no confirmed examples of this kind.

A typical example of the rapid weakening of the virus is considered the same "Spanish flu", the flu epidemic that raged a hundred years ago and killed more people than the world war. The flu mutates extremely quickly - of the known pathogens of human diseases, only HIV mutates faster. This means that the lethality of the new influenza strain is falling more rapidly than, for example, the coronavirus, which mutates much more slowly.

Influenza in the transition from person to person really quickly changes genetically so that after a year or two or three the epidemic fades - and this is exactly what happened with the "Spanish flu". However, even with her, this did not happen anywhere in two or three months, as Myasnikov expects.

Coronaviruses, known to science so far, mutate noticeably slower than influenza. Therefore, it is very doubtful that such a virus can "weaken" and "come to naught" by itself, as Myasnikov predicts.

Why, then, is the epidemic in Russia declining?

Okay, let's say the virus is really unabated. But why then do we see that some of the restrictions are being lifted in Russia, and the number of new infections is on the decline?

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We have already tried to answer this question in an earlier article "Summer against coronavirus: who will win?" But they came to the conclusion that the summer itself in central Russia is so cool that it alone will not "crush" the epidemic.

And I must say that so far the warm season has not really stopped the coronavirus in our country. The number of newly detected infected does not fall below eight thousand per day. It is only against the background of the recent eleven thousand per day, eight thousand look modest. If such a wave does not die out in the next hundred days, it will give another 0.8 million infected people and more than ten thousand deaths throughout the country.

That is, while there is no "stopping" of the epidemic - there is only some inhibition. If it does not intensify, the scale of casualties in our country could be enormous.

But still there is inhibition. If it is not explained by the mechanism proposed by Myasnikov, then there must be some alternative way. What could it be?

Among the viruses spreading by airborne droplets, the most studied is influenza, and it is valuable because the mechanisms of its spread are in many ways similar to the new coronavirus. That is why one feature is of particular value - the summer loss of activity, which happens even if the temperature does not change much.

Epidemiologist Nikolai Filatov, Corresponding Member of the Russian Academy of Sciences, describes him as follows:

“There are still things that are poorly understood today. For some reason, the influenza virus, with which they work in laboratories, loses its activity in the summer. He is in the laboratory, there the temperature is the same, there is no additional ultraviolet radiation, but at some point he stops working - as he fell into hibernation, and then he leaves it in the fall. Why? Unknown."

We should note that here the epidemiologist may not be quite familiar with some of the scientific work on the topic. Back in 2009, a group of researchers led by Jeffrey Shaman from the University of Oregon (USA) discovered an interesting phenomenon: all fairly strong influenza epidemics in the United States begin after 17 days (on average) of abnormally low absolute humidity.

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The words "abnormally low" should not be misleading. Unlike relative humidity, absolute humidity is "abnormally" low almost every year - if you live in a temperate climate. This happens in winter: the lower the temperature, the less water vapor in the air.

Moreover, the same paper notes: "Our data indicate that the start of an influenza outbreak coincides with an increase in the number of sunny days … and only with moderate anomalies in relative humidity."

That is, the popular idea that high ultraviolet light reduces the incidence of viral diseases is not sound: on sunny winter days, there is more UV, but it is followed by an increased incidence of influenza. And the relative humidity itself is not associated with flashes - only absolute.

There is nothing too surprising in this. Sunny days in winter are on average colder than cloudy ones. At low temperatures, there is very little moisture in the air: at 0 ° C, a cubic meter of air at 100% relative humidity contains 4.8 grams of water vapor. At + 20 ° C - 17.3 grams, many times more. That is, a relative humidity of 50% at + 20 ° C will give an absolute moisture content in the air of 8.65 grams - almost twice as high as at 0 ° C and a relative humidity of 100%.

Why is low absolute humidity important for the success of an airborne outbreak? In the cold season, it is warmer in the house than on the street, but the air gets into it from it. Its absolute moisture content is low. And even if this air is with high relative humidity, then, once it gets into the house and warms up, it immediately receives a very low relative humidity.

This means that water begins to evaporate quickly from the mucous membranes of the nasopharynx (and from the rest of the body): they dry out. That is why in winter, nose bleeds more often, dry skin becomes, and so on. Cracking of the integument of a person, as a rule, is noticeable only on a microscopic scale, but the virus does not need too large "gaps" to get inside.

The coronavirus spreads in general the same way as the flu - with water droplets in the air. Just like the flu, it should be much less transmitted in the summer. Weak - but does not stop at all, and here's why.

In a room where the air conditioner is operating, the absolute humidity of the air is lower than where it is not. In the office in the summer without air conditioning, it is not very convenient, especially if you are wearing a tie. And now a colleague suffering from heat set it to + 22 ° C or below - and your nasopharynx is no longer a reliable barrier to infection. Have you gone to a store, especially a large one, where you have to walk for half an hour? The nasopharynx will also have time to dry out. Left the store, got into the car, turned on the air conditioner? The same story.

The most dangerous situation is in the airliner. It takes in air from outside, where it is very cold and the absolute humidity is below a gram per cubic meter. After warming up, air is obtained with a relative humidity of 20%, or even lower. These are extremely low numbers, causing discomfort for most people and dramatically increasing the likelihood of infection, especially on long-haul flights.

It would be possible to add water vapor by artificial humidification, but … Let's be honest: we rarely do this even in our own homes, where it is inexpensive. In an airliner, the amount of water needed to humidify the air would reduce the payload, which would hurt the airline's wallet. Of course, no one will do this, and you will continue to fly in extremely dry air.

How does the absolute humidity change in Moscow and does it show a connection with the coronavirus epidemic?

Let's test the conclusions of the Shaman's group using the example of the coronavirus epidemic in Moscow. The maximum number of new infections detected - more than five thousand per day - was between May 2 and 12, 2020. It is clear that PCR does not immediately detect the disease and some of the patients caught the infection back in April. What was the absolute humidity there?

Well, for example, on April 26, the relative humidity was just below 50%, and the average temperature was about + 4 ° C. This means that the absolute humidity averaged three grams of water per cubic meter of water. On average, this April in the capital was +4, 8 ° C, absolute humidity fluctuated around 4.0 per cubic meter of air. Is it a lot or a little?

Let's compare with the same Moscow for May 1-28, 2020. The average temperature during this time was 11.5 ° C, the relative humidity is on average close to April. But due to the higher air temperature, the absolute rose to 6, 1 gram per cubic meter. On May 28, it reached 6, 65 grams.

When the outside air entered the apartments of Muscovites, their nasopharynx should have dried much less. It is clear that this concerns stores in moderation, and it is clear that an increase in absolute humidity a little more than 1.5 times is not a panacea. But it is also clear that if Shaman is right, the incidence of coronavirus in the capital in May was bound to fall.

And indeed: since May 15, the number of newly diagnosed patients has dropped below four thousand per day, since May 20 - below three thousand, and now it is around two thousand. It is quite obvious that from the end of April to mid-May, the severity of quarantine measures in the capital did not noticeably increase, and therefore it cannot explain such a decrease in the number of infected.

From this it turns out that there is a connection between the increase in absolute humidity and the decrease in the number of infected people in Moscow. And what exactly does it explain the temporary decline in the number of newly infected.

Does this mean that you can relax? After all, the summer in Moscow, although it looks like late autumn in Volgograd, is still unlikely to drop the absolute humidity below six grams.

Unfortunately, we would not say that this is enough. Firstly, even two thousand detected cases per day is 200 thousand in a hundred days. To date, there are about 170 thousand diagnosed patients in Moscow. A couple of hundred thousand more cases - this is several thousand additional victims. There is no reason to relax.

Of course, in the south of the country the situation with absolute humidity is completely different. In Makhachkala at the time of writing, it was + 23 ° C, relative humidity 59% - that is, in a cubic meter of air as much as 12.1 gram of water, almost twice as high as in Moscow. It should be objectively easier to stop the epidemic there.

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But the key factors in our life are not objective, but subjective. To understand what we are talking about, it is enough to open the press: “Even if they know that this is a virus, that it is possible to get infected, 90% will go anyway, because not going will be a kind of“shame”. People think, well, I’ll get infected, I’ll be cured, but if I don’t go, it will be a shame, it’s for a long time. This is what people have in mind,”says 35-year-old Rasul Asad from Khasavyurt.

And a funeral there is not a funeral in Moscow. “About a thousand people gather in our village. They are in contact as closely as possible for at least three days, they say, hug, eat. Therefore, I believe that the funeral played a major role in the spread of the virus in Dagestan,”says Akhmed, a resident of another settlement in the republic.

As we can see, in Dagestan there were problems with the simplest quarantine measures. Some of them have been resolved, but there are doubts that all have been resolved: it is difficult to change the mentality in a month. Therefore, even here it is difficult to hope that absolute humidity will stop the epidemic at once.

Best of all, business with it will go in those regions of the country that are warmer and more humid than others, but where the decomposition of traditional society has gone as far as possible, which is why people are most disunited and communicate with each other the least intensively.

So after all, will the virus fizzle out?

Let's go back to Dr. Myasnikov. He makes a conclusion about the new coronavirus: “That's it, run out of steam. Ate the virus, sucked our blood and fell off. Let's hope for a long time.But in any case, if the mutation does not occur, then he will not do a big trouble (unless he is again appointed a "villain" by the media)."

Unfortunately for us, this is not the case. Yes, now the absolute humidity is growing, moreover, the heating is turned off, and citizens are gradually turning off the heaters. Their mucous membranes dry less and less, that is, all other things being equal, the likelihood of infection with a new virus decreases. The main problem is precisely "other equal".

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Even if the population does not relax, does not forget about social distancing measures, and by July the epidemic will rise - it will not completely disappear. She already has too many speakers in Russia. And there are too many air conditioners around the modern person, which will allow the virus to infect new people "drop by drop" until the fall.

In the fall, the absolute humidity will drop again and inevitably, following the temperature. Instead of 10+ grams of water per cubic meter of air in summer, we will again feel 3-4 grams on ourselves, and in winter - less than one gram per cubic meter. That is, without a vaccine, the epidemic will not go anywhere, since Russia is not China and could not organize a full-fledged quarantine.

Will there be a vaccine by the fall? As we all understand, this is a very big question. And if the answer to it is negative, the virus can bring even more troubles in the fall and winter than it did in the spring. The way it was with the "Spanish".

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