How dangerous is the Chinese coronavirus? 13 answers to the main questions

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

The new coronavirus - a "relative" of the old SARS - has already killed 26 people. It is believed that several thousand can be infected with it. And it is known for sure that the epidemic has spread beyond China. But this is not a reason to panic. We have collected all the known information and tried to answer the main questions about the new disease.

1. Everywhere they write about this virus. Is it really that serious? Wasn't that the case before?

Definitely, the new 2019-nCoV coronavirus is serious. As of the morning of January 24, 893 cases and 26 deaths are known, that is, the mortality rate due to illness is 2.9%, and this percentage may increase (some of the cases are in critical condition). Given the incubation period, there can be several thousand infected in total, and the number of victims can reach hundreds.

Something similar has happened before: SARS in 2002-2003 infected eight thousand people and killed 775 of them. It also spread from China and also originated initially from contact with animals (bats), which were the reservoir for the base form of the SARS virus. The then pathogenic virus was also a coronavirus and genetically coincides by 70 percent with the new one. That is, that SARS and the new epidemic are relatively close "relatives".

At that time, the spread of the disease was contained by quarantine measures. The new coronavirus is reliably transmitted from person to person. If it is not contained with quarantine measures, 2019-nCoV could theoretically kill many more people.

2. Is the new coronavirus dangerous for young people or only for those who are older?

It should be clearly understood: 2019-nCoV is just another virus that can cause pneumonia. Therefore, the chances of dying from it are higher for those who have them higher and with ordinary pneumonia. That is, first of all, in those who later consulted a doctor with symptoms, and, secondly, in those who are older or suffer from chronic diseases, including the respiratory system.

Take the same SARS, the related coronavirus epidemic 18 years ago. According to the WHO, the chances of dying from it were, on average, 9%, but for those under 24, it was below one percent. At the age of 25-44 - up to six percent, 44-64 - up to 15 percent, 65 and older - above 55 percent. This does not mean that young people have nothing to fear, but it certainly does mean that older people should think about it.

It is highly likely that this will be the case with new pneumonia, whose causative agent is a "relative" of the atypical one.

3. Is it possible, in principle, to create a new virus that will kill many people, and we will not have what to protect ourselves with?

This story takes place systematically. Take the measles virus: genetics have established that around the 11th-12th centuries it was a common virus in cattle. Then he mutated so that he could spread between people: and began to kill millions. Back in 1980, 2.6 million died from it, and it still infects 20 million a year. According to the WHO, even in 2017, he (albeit not without the help of antivaccinators) killed 110 thousand people. As we can see, SARS is just a trifle against this background. She was so seriously covered in the media only because they love everything new and unusual.

Moreover, even the “relatives” of 2019-nCoV constantly infect us: among other things, coronaviruses cause a runny nose, they often hide behind the acronym ARVI, and so on. Normally, the virus stably exists only if it does not threaten the carriers with frequent death. Because each such death means that the number of carriers decreases and with a large-scale epidemic there will be so few of them that sooner or later the epidemic will end. This means that there will be fewer active viruses.

However, sometimes in the realm of viruses "abnormal" lines appear. For example, one of the fastest mutating viruses, influenza, in 1918-1919 infected a third of the world's population and killed at least 50 million people (the Spanish flu epidemic). This is several times more than died in the First World War and about the same as died in the Second.

Fortunately, today we have medicine that is rapidly making vaccines. Weakened forms of the virus are grown in a short time, vaccination will dramatically reduce mortality from any analogue of the "Spanish flu".

There is one scenario where a virus could theoretically kill many people at once, despite vaccines. Take HIV: it affects part of the immune cells, so the immune system does not cope well with it. It is so difficult to create a vaccine against it that only now its first trials are underway - although the virus itself has been known for decades.

If an airborne virus appears, like the new coronavirus in China, but at the same time infects immune cells, like HIV, then it will not work quickly to create a vaccine from it. In this case, a large number of victims is possible and there will be no protection from such a virus for a long time.

The likelihood of such a development of events is small: the virus specializes in the defeat of one type of cells. The same HIV, in order to attack the cells of the immune system, is looking for those with CD4 receptors among them. But among the cells in the respiratory tract, there are not very many of these: in non-immune cells, such receptors are rare. So, normally, the virus can be either intractable, like HIV, or easily transmitted, like measles.

Perhaps these traits can really be combined artificially - and get a virus that infects both immune cells and ordinary cells of the body, including in the respiratory tract, in order to make it highly infectious. For example, this might make sense when creating biological weapons. But so far the technologies available to geneticists are extremely far from the level required for such a combination.

4. How can you reduce the likelihood of contracting a new virus?

Like most coronaviruses - that is, like with a common cold. First, try to avoid contact with possible carriers. The new coronavirus comes from the genes of the bat coronavirus and the Chinese venomous snake. Presumably a Chinese cobra, although the snake hypothesis raises questions. Both are traded in Chinese markets with exotic animals that are eaten there.

The epicenter of the new epidemic is Wuhan, and there it went from the local seafood market, where they sell all these cobras and the like. Due to the recombination of genetic materials of two lines of coronaviruses in this market, 2019-nCoV arose. Therefore, we strongly advise you not to visit Wuhan and, to be honest, China in general - at least until the epidemic is dealt with there. It is worth recalling that it has already reached Thailand (several cases of the disease), South Korea, Japan, the United States, Singapore, Vietnam and Saudi Arabia, so it is better to postpone trips there until the situation becomes clearer.

If you are already in China, avoid seafood markets and exotic animals, drink only bottled water and do not consume foods that are not processed at high temperatures: analogues of sushi and ceviche, as well as uncooked meat.

And wash your hands constantly after visiting public places and meeting new people. All viruses transmitted by airborne droplets are actively deposited on the hands, because people touch their mouth and nose with them on average 300 times a day. In experiments, one person with a viral infection, who touched the handle on the door in a large office, leads to the fact that the virus ends up on all the handles in the office (healthy employees carry it further with their own hands). Therefore, special attention should be paid to hand hygiene. If you can't wash your hands every time, use alcohol wipes.

5. Should you buy masks in advance? Which ones?

Oddly enough, such coronaviruses do not spread "from one sneeze." The fact is that all viruses are specialized for the base carrier. Some of the 2019-nCoV genes were inherited from a bat (body temperature varies widely, much more than in humans), some from a cold-blooded snake (the temperature is much lower than a human). This means that the new coronavirus is not ideally suited for human-to-human transmission.

Nevertheless, masks reduce the likelihood of infection with them - and noticeably. However, it makes no sense to buy them in advance (so far there is not a single confirmed case of the disease in Russia), as well as to bother choosing a particular type of such a mask. Almost all of them are close in their capabilities today. If it nevertheless comes to an epidemic in our country, it is worth remembering that the mask must be changed at least once every few hours.

6. How long does it take for the virus to manifest itself? How to understand that you are ill?

The incubation period of the virus is about five days. That is, if you returned from China or other countries where the epidemic already exists, then only after about a week of no symptoms can you begin to relax.

An elevated temperature indicates infection with 2019-nCoV: an increase can be moderate or severe, but there is in 90% of cases. In 80% of cases, there is a dry cough and quickly onset of fatigue. Shortness of breath and shortness of breath are much less common. Pulse, breathing and pressure in the early stages are normal - there is no point in checking them.

It is worth consulting a doctor if these symptoms are found in anyone who has been to countries where the epidemic has penetrated. A specialist will be able to make a diagnosis based on a snapshot of your lungs: there the new coronavirus leaves traces typical of pneumonia.

7. And if you got infected? What to do?

First of all, don't panic or get depressed. These are not just soothing words: 17 years ago, studies showed that with negative emotions (or memories of sad situations), a person's level of antibodies in the blood drops dramatically. To put it bluntly, nature does not need losers and those who experience depression. Therefore, being discouraged during an illness is the surest way to reduce the body's ability to resist it.

Meanwhile, your own immunity is especially important if you catch 2019-nCoV. There is no specific treatment for it yet, although it is believed that a number of antiviral drugs for other coronaviruses may help.

Therefore, in case of infection, you should calmly follow all the recommendations of the attending physicians (and not "treat" yourself at home) and not get nervous again.

8. Is it safe to receive parcels from Aliexpress now? Or is it better to leave at the post office and walk around without a new phone case?

Today there is no clear understanding of how long this virus can survive outside living organisms: the very existence of the epidemic was realized only a week ago. It is possible to express only general considerations about whether this virus is capable of being transmitted with objects.

Viruses are normally classified as “smart” and “durable”. Durable have a shell that protects them well from the external environment. The smart ones are the big genome. 2019-nCoV is a rather "smart" virus, with a relatively long RNA (record long in its class of viruses). Therefore, the shell protects him weakly: he lives in the owner, where it is already warm and comfortable. They won't last long outdoors.

Russian delivery services - from, not by nightfall, "Russian Post" to its commercial counterparts - do not work quickly. Almost certainly, by the time the package arrives at you, 2019-nCoV will die there. But to calm your conscience, you can wipe the cover with an alcohol napkin.

9. Is it more dangerous than swine and bird flu?

It depends on what you mean by these words. The fact is that the same "Spanish flu", according to some researchers, arose from the recombination of genes of the poultry and human influenza virus (H1N1 strain). This "hybrid" flu gave rise to the most dangerous known viral epidemic in history, killing at least fifty million people.

However, usually no one knows about this. Following the media, bird and swine flu is called epidemics from China, which have been there periodically since the 1990s. Avian is called H5N1. It was less dangerous, since it spread normally only from poultry (chickens) to person, and from person to person it was rather bad. However, if they do get sick, then the risk of death could exceed 50 percent, which is a lot. In total, 630 people were infected with it, 375 died.

Swine flu is called the A / H1N1 flu pandemic in the media. In fact, it is not a fact that it was transmitted to humans from pigs - it is more likely that this is the result of the recombination of genes of one flu, typical for pigs, and another, typical for humans. In fact, this is an ordinary flu with a very low mortality rate among cases (one in 3000), and, as with ordinary flu, mortality is due to complications. Among the cases of A / H1N1, 17 thousand died, which is a lot. But it is worth remembering that, according to WHO, 250 thousand people die annually from influenza (or rather, its complications) in the world.

Of course, such a "swine" (but in fact not - among pigs its epidemic has not been recorded) flu is much more dangerous than the new coronavirus in terms of the total number of deaths. But those who contracted it in 2009-2010 had a 0.03 percent chance of dying. Among 2019-nCoV patients, this probability is still nine percent, that is, 300 times higher.

10. Do people recover completely after it or do problems remain?

At the moment it is unknown: the number of cases is too small. However, normally, after an untreated viral pneumonia, the overwhelming majority of those who have recovered do not have any problems.

11. How often do such viruses appear? Were you as dangerous before?

Viruses transmitted from animals to humans appear periodically, even in our time. For example, Middle East respiratory syndrome, caused by another coronavirus, appears to have emerged as early as the 21st century. During 2012-2017, two thousand people fell ill from him and more than 700 died.

Initially, a person became infected from a sick one-humped camel, which is why most cases occurred in the Arabian Peninsula. However, in the age of globalization, such patients can often travel a great distance, so one person from Saudi Arabia brought the virus to South Korea, where it killed dozens.

The emergence of new viruses of this kind is the norm. Most viruses have a much higher mutation rate than multicellular viruses, and they often combine the genetic material of different strains, which leads to their high variability and often the emergence of new strains. Nevertheless, in the conditions of modern medicine, the number of victims from such viruses is quite small - about hundreds per epidemic.

12. So is it worth or not to panic in the end? Will they find a vaccine for him soon? Or maybe not find her at all?

You shouldn't panic at all: as we noted above, negative emotions can seriously suppress your immune system, which will reduce its ability to fight. And not only with 2019-nCoV - a rather exotic disease - but also with the closer and more dangerous common flu, with its complications. And not only with the flu. More than a quarter of a million people per year die from pneumonia of all types, and with reduced immunity, the chances of being among them increase.

As for the vaccine, in theory it is "almost there." In laboratories, based on 2019-nCoV, coronaviruses of one reproduction cycle have been created. Such can enter the body and even once create their copy there, but then they cease to be active. This is, in fact, already a vaccine - thanks to the presence of 2019-nCoV in one reproduction cycle, the immune system learns to develop the desired response.

But there is a nuance: any vaccine requires lengthy checks for its complete safety, and this is not done quickly. And epidemics like SARS or its cousin 2019-nCoV often end quickly. The same SARS lasted for about a year. In such a short time, no one will establish any mass vaccination, therefore, most likely, the fight against the epidemic will be reduced to quarantine and treatment of those already sick. By analogy with SARS 2002-2004.

A vaccine against the coronavirus, which infects the body's non-immune cells, is almost guaranteed to be made. To make it difficult to create a vaccine for a virus, it must be of the type of HIV - that is, it must attack not ordinary cells, but cells of the immune system. Roughly speaking, it is difficult for the "police" of an organism to catch a criminal virus if it is ideally adapted to hunt for "cops".

Coronaviruses do not do this, so you should not be afraid of the impossibility of creating a vaccine specifically for a new epidemic.

13. They also say that the Americans could have done this virus, everything happened just before the Chinese New Year. Is there a grain of truth in this?

Such rumors arise regularly: even in the days of SARS, two Russian researchers suggested that this is an American virus. However, after studying the RNA of the virus, such "hypotheses" dissolve like smoke.

The RNA clearly shows that both SARS and the new 2019 coronavirus are close "relatives" of the coronaviruses of bats and poisonous snakes that live specifically in China. Moreover, they are sold in exotic food markets in Wuhan. It is due to the fact that 2019-nCoV originated from such a mixture of genes that it does not spread very well (judging by the available data) among people.

If this virus were created artificially, then for such a result its developers would be worth firing for incompetence. A virus that is not very well transferred between people is a bad weapon.

If the "creators" made it easily transferable from person to person, they should be fired all the more. SARS 2002-2003 caused dozens of deaths in Canada. A highly contagious virus would easily reach the United States and cause an epidemic there as well. In the age of mass air travel, creating a virus for China means preparing an epidemic at home.

In theory, you can try to create a virus that will not infect people without special genes, and try to find such genes only in the Chinese. In practice, given the current technological level, this is about as real as the real colonization of the Tau Ceti system.

The available means of genome manipulation are too crude and imprecise to fulfill such an ambitious task. In addition, infections with the new coronavirus have already been registered in other countries, which excludes the version of "anti-Chinese" biological weapons.