“Infectious diseases appeared earlier in history than humans, and they will coexist with humans for a long time in the future, and it will also be a basic parameter and determinant of human history as before.” Famous American History The scientist William H. McNeill wrote this famous sentence in his book “The Plague and Man”. We never know how close humans are to a major biological disaster.
In the second half of the 5th century BC, an outbreak in Ethiopia went north along the convenient trade lane to ancient Greece. In 430 BC, during the second year of the Peloponnesian War between Athens and Sparta competing for the Greek hegemon, the epidemic broke out in Athens. Due to the lack of proper treatment, prevention and control methods, the epidemic swept through Athens and “people died like sheep.” Death and turmoil directly led to the defeat of Athens in the war, quickly reduced to a second-tier city-state, and the decline of ancient Greek civilization.
The Roman Empire has been tortured by “the whole life” of the plague, such as the Anthony Plague and the Cyprian Great Plague. The “barbarians” and “bordermen” caused barbarism. When even the army had to rely on Germanic barbarians to hire soldiers, the Roman Empire declined. In the dark Middle Ages, the outbreak of the plague caused about 24 million deaths, and changed the direction of European history. When prayer and redemption could not save the lives of priests and even bishops, the authority of the Catholic Church plummeted, and the Renaissance and Enlightenment movements followed. Come from. Some Western scholars believe that the end of the Black Death also marks the end of the Middle Ages.
With the great geographical discovery and colonial exploration, the plague also came to the Americas which were “independent” in the past. Because the indigenous peoples were not immune to the diseases of the Europeans, a very tragic scene appeared: after Columbus arrived in the Americas, it was In 42 years, the population of Hispaniola Island (now Haiti, Dominica) with 8 million indigenous peoples was reduced to zero; the Spaniards who landed on the Mexican coast brought smallpox to the Aztec Empire. In 100 years, 2 Of the 10 million Inca populations, there are only about 1.6 million left, and it is rare for Native Americans to originate here today. During the spring of 1918-1920, the Spanish pandemic caused approximately 1 billion people worldwide and nearly 40 million deaths. The World War I had no possibility of continuation and directly changed the world pattern at that time.
It is true that of the many factors that have changed the course of human history, the plague may be the most brutal and cruel way. The plague was a cemetery in ancient times and a battlefield in modern times, but it is more like a strict examination room in modern times. The state, disease control departments, doctors and even individuals are all candidates who use knowledge, behavior and even life to answer in this examination room.
In 2003, SARS engulfed the whole world. Everyone was in danger, and it was still a nightmare in the hearts of many people. It was a major test for the prevention and control system of infectious diseases in China, and it also contributed to the reform and improvement of the subsequent disease control system. From December 2019 to the present, SARS’s “same door”, a new coronavirus outbreak in Wuhan, a new epidemic is coming.
● “Teachers go out in the same room”, the epidemic appears
On November 30, 2017, the team of Shi Zhengli of Wuhan Institute of Virology, Chinese Academy of Sciences, after more than ten years of research, found a natural gene bank of bat SARS coronavirus in Yunnan, China, and found almost all SARS coronaviruses, revealing SARS coronavirus The virus recombination originated in bats. So far, the outbreak of SARS in 2003 has been thoroughly clarified, and the origin of SARS has also been revealed. The research team found that some of the viruses detected have the potential for cross-species infection. “Although SARS has not made a comeback for so many years, in nature, this virus that is similar to SARS actually exists. If we humans are not vigilant, then the next virus infection may be direct infection, or it may pass through other animals. Infecting humans, this possibility is completely present. “This is what Professor Shi Zhengli said in a public speech in 2018, but he did not expect to be” a word of proverb “a year later.
On the morning of December 26, 2019, in an area near the hospital where Zhang Jixian, director of the Department of Respiratory and Critical Care Medicine of the Hospital of Integrated Chinese and Western Medicine in Hubei Province, an elderly couple came to see a doctor because of a fever and cough, but the lung CT performance was different from other viral For pneumonia, she then inspected the son of the old couple and a vendor in the South China Seafood Market, and she found that the condition was surprisingly similar. On December 28th and 29th, the outpatient department of the hospital successively admitted 3 patients from the seafood market in South China. These 7 patients caused Zhang Jixian and the hospital to be highly vigilant. After discussion, they immediately reported to Hubei Province , Wuhan Municipal Health Commission. On December 30, the Wuhan Municipal Health and Health Commission issued the “Urgent Notice on Reporting the Treatment of Unknown Pneumonia” to start investigation and statistics. On New Year’s Day in 2020, the South China Seafood Market was closed and the expert team began collecting environmental samples. On January 3, China first notified the United States and the World Health Organization (WHO) of the epidemic situation.
At 21:00 on January 7, 2020, a new coronavirus was detected in the laboratory, and the whole genome sequence of the virus was obtained. The expert team initially determined that the pathogen of this unexplained viral pneumonia case in Wuhan is a new coronavirus-this It is the seventh coronavirus known to humans. On January 12, the viral gene sequence was completed and announced. On this day, a total of 41 cases of pneumonia infected with new coronavirus were reported, 7 cases were cured and discharged, 6 cases were treated seriously and 1 died. On January 15, the China CDC launched the first-level emergency response to public health emergencies, which is the highest level of public health response and means that the matter is “particularly significant”.
On the afternoon of January 20th, Academician Zhong Nanshan led a panel of experts to hold a press conference at the National Health and Health Commission, and clearly announced that there is a “human-to-human transmission” of the new coronavirus pneumonia in Wuhan.
At 2 a.m. on January 23, Wuhan City announced that from 10 a.m. that day, the Lihan Passage will be temporarily closed. On this day, the National Health and Health Commission received a total of 830 confirmed cases of pneumonia with new coronavirus infection in 29 provinces (autonomous regions and municipalities), including 177 severe cases and 25 deaths. It is on this day that the construction area equivalent to half of the “Battlefield Hospital” of Beijing’s “Water Cube”-Vulcan Hill Hospital started construction.
On January 26, researchers for the first time detected 33 new samples of coronavirus nucleic acid from 585 environmental samples from the South China Seafood Market, and successfully isolated the virus from positive environmental specimens, suggesting that the virus originated from the South China Seafood Market. wild animals.
On February 2, the Vulcan Hill Hospital was successfully checked and accepted. It took only 10 days from the beginning of design to completion. On February 8, 2020, Wuhan Lei Shen Shan Hospital was delivered for use. The first batch of medical staff was stationed and the first batch of patients was admitted that night.
On February 8, the State Council Joint Defense and Joint Control Mechanism held a press conference to temporarily name “new coronavirus-infected pneumonia” as “new coronavirus pneumonia”, or “new crown pneumonia” for short.
As of 6:00 on February 12, 2020, there were a total of 44,742 confirmed cases, 16,067 suspected cases (including 8,204 severe cases), 4,771 cured cases and 1,114 death cases. The spread of the disease has exceeded SARS and is the most serious public health emergency in China since the SARS outbreak in 2003.
● Coronavirus, where did it come from
Coronaviruses are relatively common in nature. Different coronaviruses can infect a variety of mammals, such as bats, humans, cattle, pigs, and birds. In 1965, Tyrrell et al. Isolated a virus from the nasal washes of patients with common colds using the method of human embryo tracheal culture and named it B814. Subsequently, Hamre et al. Isolated a similar virus from human embryonic kidney cells and named it HCoV-229E virus. This was the earliest coronavirus discovered.
Although coronaviruses are widespread in animals such as bats, up to now, only a total of 7 coronaviruses that can infect humans have been found in humans. Among them, severe acute respiratory syndrome coronavirus (SARS-Cov), Middle East respiratory syndrome coronavirus (MERS-Cov) and 2019 new coronavirus can cause fatal respiratory diseases. The four coronaviruses HCoV-229E, HCoV-NL63, HCoV-HKU1, and HCoV-OC43 are common pathogens of human colds and usually do not cause serious diseases. A few patients with poor immunity may have complications such as pneumonia after infection.
Professor Wu told us that coronavirus, as an upper respiratory tract virus, is a common pathogen that causes upper respiratory tract infections in winter and spring, but in the past everyone may not have paid much attention, because the symptoms caused by it infected humans and flu, avian flu, etc. Basically similar. The emergence of SARS has greatly changed people’s attitude towards coronavirus. In 2003, data released by the World Health Organization showed that there were 919 deaths from SARS in the world, with a mortality rate of nearly 11%. According to a report from the former Ministry of Health Information Office, there were 5,327 SARS cases and 349 deaths in mainland China. The research on coronaviruses has begun to receive attention, and coronaviruses carried by animals have also been regarded as key research objects.
Coronaviruses are mainly found in small mammals, the most important being bats. “This coronavirus is homologous to SARS, and some of its structure has changed, so its structural area is closer to SARS, and its infectivity to humans is relatively strong, and it is mainly based on the invasion of the lower respiratory tract.” Wu Said the professor.
● Why is it a bat? Why is game
As the second largest mammal in the world after rodents, bats are distributed in all parts of the world except the poles, and have diverse habitats. As a member of the biosphere, bats play an important role in maintaining ecological balance. At the same time, it is also an important virus host, carrying more than 130 kinds of viruses, including Ebola virus, Nipah virus and other potent pathogens.
“A bat can carry more than one hundred kinds of viruses without disease, which is called a mobile ‘virus bank.” It can carry a large number of bacteria without getting sick, which is related to the particularity of bats. The human body cannot suppress and kill pathogenic microorganisms without our immune system, but this system is not highly activated at all times, and the immune system is “full power” only when it is infected and fevers. time. Many people know that long-term fever may be “stupid”. Our body cannot withstand the high temperature caused by the high activation of the immune system for a long time, but bats that are also mammals can.
The bat accidentally acquired the ability to repair genes in a mutation evolution millions of years ago, which gave it a good “capital” to turn on the immune system for a long time without fear of damage. The intuitive performance is the body temperature of the bat It is usually 40 ° C (also related to the fact that bats as the only flying mammals need high-speed metabolism), which may be even higher, which makes it difficult for most pathogenic bacteria to cause damage to bats. In peaceful coexistence, bats become mobile “Virus database”. When the virus of a certain bat spreads to humans across species, we cannot bear it if we cannot always activate the immune system.
If the bat is the source, the game that was put on the human table may be a “blood” blade. Except for rabies caused by bat bites, few cases of bats directly transmitting diseases to people are heard. However, bats pass viruses to intermediate hosts, such as raccoon dogs, pangolins, and bamboo rats, by eating saliva, excrement, or other means. These animals are more likely to be bred and killed by humans. During the polyculture of wild animals, viruses can spread and mutate more quickly, causing human infections during handling, transportation, and consumption. “In 2003, it was Yunnan’s bat that transmitted the virus to the locally-raised civet cats, and this group of civet cats was sent to the table of the Cantonese.”
● Proper protection, not in trouble
At present, in official explanations, the spread of new coronavirus is mainly droplet transmission and contact transmission. Under special conditions, aerosol transmission can be formed, and fecal mouth transmission has not been determined. “Among them, droplet transmission and contact transmission are also the transmission methods of almost every respiratory virus.” Professor Wu emphasized.
The spread of droplets is well understood. Every time a person sneezes, coughs, or talks, a certain amount of saliva is ejected. Coronavirus can exist in the scattered droplets of saliva, and the “concentration” of the virus is large and the infectivity is also relatively high. Strong. When healthy people directly inhale droplets with more viruses, the viruses will directly invade the respiratory tract mucosa of the human body and cause infection. It is not difficult to find that droplet transmission is currently the most important method of transmission and the most contagious method of transmission. In the case of a recent food shopping conversation in Ningbo (without wearing a mask on both sides), people were infected within 15 seconds, and droplet transmission was the cause.
However, the spread of droplets is limited and not difficult to prevent. Under normal circumstances, large droplets will quickly land on the ground, and small droplets will briefly stay in the air, but are limited to the source of infection. Therefore, the spread of droplets can only affect close contacts around the source of infection. In the absence of wind, propagation above 3 meters is almost impossible. On the other hand, it is strongly emphasized that all people strictly wear masks when they are in public areas and places. If they wear masks correctly, they can ensure their safety in the case of droplet transmission, and potential patients will not produce masks after wearing them. When more droplets are sprayed into the air, it is a good protection for everyone.
Contact transmission is also one of the main ways of spreading new coronaviruses. After leaving the human body, the virus can survive on the surface of the object for a period of time. According to the latest news, the virus may survive for several hours after falling on the smooth surface with droplets, etc., and the temperature and humidity are more suitable, the virus can survive longer time. If our limbs come into contact with objects carrying viable viruses, we will touch the rich mucous membranes such as the mouth, nose, eyes, etc. after being contaminated with the virus, or directly touch the wound, the virus will enter the human body, and will reach a certain amount. Cause infection. “More intuitively, this can also be called ‘dirt spread.'” Professor Wu said.
Therefore, hand hygiene is very important in the face of this epidemic. Every time when you go out, your hands should never touch your mouth, nose, and eyes again. You must wash your hands in the right way after returning home.
There is currently no more research evidence regarding the risk of aerosol transmission. An aerosol is a kind of suspended particles with a diameter less than 100 microns. The familiar PM2.5 is a kind of aerosol, and the aerosol transmission of virus refers to the protein and pathogens left by the water lost during the air suspension process. The formed nucleus, which forms a droplet core, can float to a distant place in the form of an aerosol, causing long-distance propagation. Aerosol formation first requires the release of large amounts and high concentrations of virus particles into the air at one time, so the formation of virus-containing aerosols is mainly related to the invasive operations in hospitals for patients with new coronavirus pneumonia, such as tracheal intubation and tracheotomy . Daily coughing and talking will not form an aerosol, even if it is formed, the amount is small, plus the virus’s poor viability in the natural environment, and the dilution effect of the air after the aerosol is scattered, it is difficult to reach the amount of virus that can cause human infection Therefore, under the current control situation, people in other areas can effectively protect themselves without worrying, except in high-risk areas, such as hospitals and isolation wards where airway operations must be performed.
As for the spread of manure, it is also an unclear method of spread. The previous research also confirmed that the virus can replicate in the intestine of the patient and cause infection. Recently, a team has also detected positive virus nucleic acid in the stool of the patient. It has also been reported that the active virus strain has been found in the stool of the patient, but whether the new coronavirus can pass The new infection caused by the “feces-mouth” approach is not yet clear, and there are currently no cases of infection via this route. You don’t need to worry, wash your hands frequently, strictly wash your hands before and after meals, and pay attention to the sanitation of your living environment, you can kill most of the diseases transmitted by the feces.
It is worth everyone’s attention that the incubation period of patients with new coronavirus pneumonia is infectious during the incubation period, and asymptomatic diagnosed patients have also been found, which makes it more difficult to prevent and control, but as long as we strictly pay attention to personal protection, do not go In crowded places, there is basically no need to worry.
● This is a test for everyone
How should we answer this exam? Personal protection is the most important one. Wearing a mask when going out is necessary and necessary, and is the most important way to protect ourselves and others. In terms of protective effect, N95 masks and medical surgical masks are better than thin medical nursing masks, and ordinary cotton and flannel masks have almost no protective effect.
Masks must be worn correctly to really protect them. When wearing a mask, you should avoid touching the inner surface of the mask (mostly the colorless side). The side with the metal hard strip is on the top. Press the metal strip to fit the bridge of your nose, and the edges of the mask closely fit Face, do n’t expose your nose to the outside, or leave a big gap around the mask because it feels dull, and you ca n’t lift the mask or take off the mask to breathe. These practices will expose yourself and others to danger. .
Hand hygiene is the most important protective measure in addition to wearing a mask. “Not just new coronaviruses, almost all respiratory-borne viruses can be transmitted by contact.” If the virus-infected hands touch the damaged skin and mucous membranes in the mouth, nose, and eyes, it may cause infection. The most important thing for hand hygiene is to wash hands carefully after going out. It is recommended to use running water and soap or hand soap to wash hands thoroughly in 7 steps. Note that the distal end of the wrist or forearm that is exposed when going out may also be contaminated. It is recommended to wash it together when washing your hands.
When going out, it is recommended to prepare wet tissues, disposable hand sanitizer, hand disinfectant, etc., so that you can clean your hands in time when you need them. If necessary, you can wear gloves to touch objects in the public area, such as door handles, doorbells, elevator buttons, etc., but if you can do not touch the nose and mouth, and the hand does not need to be protected from wounds, mucous membrane damage, The protection of gloves is not necessary.
At present, most of the commercial and trade complexes, movie theaters, KTVs, restaurants and other entertainment and dining places have been shut down, public transportation has also reduced the number of flights, and limited food courts, pharmacies, supermarkets and other shopping places are also open for limited time and current. At the national and government levels, efforts are made to limit the gathering of people. In order to reduce crowd gathering, the Spring Festival holiday was extended, and the time for the company to resume work was extended. What we can do, and what we should do most, is to support epidemic management and control, try not to go out, go out as little as possible, and reduce crowds.
“This virus is not so terrible. As long as it can be properly prevented and treated correctly, most people are very safe.” Professor Wu said. As of 24 o’clock on February 11, 2020, the number of newly diagnosed cases in all regions except Hubei has dropped by eight consecutive times. Perhaps the inflection point of the epidemic is in the near future. Academician Zhong Nanshan also predicted that the epidemic may peak in mid-to-late February, and the epidemic in April should be able to be effectively controlled. “Even if the epidemic is prolonged, it is difficult to extend it to May or June. After all, the new coronavirus is more fragile in the natural environment, and it is neither resistant to high temperatures nor ultraviolet rays, and there is almost no possibility of extending to summer.” Professor Wu said.
When we look forward to the end of the epidemic and taking off our masks to “freely breathe”, we might as well think about the question: Is it true that the epidemic is over, and washing hands and wearing masks will be no longer a problem with us? It can be said that hygiene awareness is an important factor to measure the level of civilization. In particular, the two items of “scientific use of masks” and “attention to hand hygiene” should become our daily hygiene habits, not just a passive behavior driven by fear during an outbreak.
Many people have no shortage of colds. One or two patients with colds may appear in the office, classroom, or home. After a while of coughing or sneezing, people in the same room may have a cold. Some people sometimes ridicule: “It’s almost time to infect others!” “The mask should be used at this time.” Professor Wu said, “Already infected, especially those with infectious respiratory diseases, wear a qualified The mask can reduce or even isolate the spread of pathogens. “We cultivate this kind of health awareness, which is kindness to others. In general, healthy people do not need to wear masks when outdoor activities are sparse, “but patients should wear masks at any time, any occasion and place! When the individual has fever and symptoms of respiratory tract infection, go out You should voluntarily wear a mask when you are active. This is a civilized and self-interested behavior. It should be respected and advocated for a long time, which will greatly reduce the probability of patients spreading to others. “Dean Wu emphasized.
As for hand hygiene, the simple “wash hands before and after meals, go home to wash hands”, many adults may not do as well as children who are stressed and educated every day. If you can really develop such a habit, the incidence of most respiratory and fecal mouth-borne diseases will be greatly reduced.
What is the test of the epidemic? Is it just the “resilience” of our society, the solidarity of “one side is in difficulty, eight parties support”, and the handling and response of sudden public health incidents? It is more about testing everyone’s health awareness and epidemic awareness and prevention ability.
● Write at the end
In fact, from time to time, countless narrators in history have tried to attribute the plague to the powers of gods and demons. The legend of Pandora’s Box and the image of the devil in the classics of the Black Death are all instinctive reasons that people attribute the plague to humans. Because the ancients had a limited level of knowledge, it was justifiable to classify plagues as ghosts and gods, but now that scientific cognition has become mainstream, it is not difficult to find that these plagues are mostly human disasters.
It is now believed that the cause of the Black Death outbreak is mainly related to war and the slaughter of witches. When fighting against the Europeans, the Mongolian army deliberately threw sick and dead rodents into the enemy’s city, using the plague to win the war. The medieval Europeans slaughtered the so-called witches in large numbers under the ignorance of ignorance, which also caused cats considered to be witch assistants and pets to be almost extinct for a long time. The number of mice increased geometrically, which made black The conditions for the onset of death are fully available.
Ebola and AIDS, although unidentified, may never be able to confirm how they came to humans from the primate community deep in the rainforest, but it is generally believed that this may result from human invasion of animal territory or hunting. SARS in 2003 is today’s new coronavirus pneumonia. Some people’s behavior of catching and eating wild animals may have played a fundamental role in the outbreak. With the continuous expansion of human towns and farmland, how many animals are forced to “leave their homes”, or live together with humans, and how many viruses are lurking around us, waiting to one day complete the species’ leap. Properly handling the relationship between humans and wild animals, and between humans and nature, may be the fundamental way for humans to protect themselves.
Faced with the plague, how should humans build a protective wall? When a plague breaks out, it has two basic characteristics at the same time: disease and infection. Often the earliest manifestation of an epidemic is that a certain patient or certain patients find abnormalities in a specific specialist clinic, and after the outbreak is a response to the emergency treatment system for public health emergencies. Looking back at this epidemic, we can find that, especially in the early stage of the epidemic, everyone’s attention is still too focused on the “pathogenic” feature. “Putting attention on the critically ill patients, the Department of Respiratory Medicine and Intensive Medicine effectively intervened and tried their best. Of course, it is necessary to treat patients, but early attention and attention to the “infection” feature are not enough. Because how to prevent infection, interrupt transmission, and reduce serious illness are the most urgent and critical. “Professor Wu said. In fact, in general hospitals in every country, there is a group of doctors specializing in dealing with “small creatures”-infection doctors. Infectious diseases are different from ordinary diseases. The thinking of infectious science is more focused on discovering pathogens, finding the source to block the spread, and studying how to prevent early infections from developing into serious diseases. It seems to be born to “contain infectious diseases”. It can be said that the infectious department of general hospitals, as the group with the most suitable professional skills, should have a non-negligible role in the national major infectious disease prevention and control system, and should also play a more and stronger role than now. Infectious diseases are detected early and prevention of infection is promoted. The Department of Infectious Diseases and the Department of Microbiology and Medicine are further integrated to increase investment, so that the infection department of the hospital has the ability to systematically inspect known and unknown infectious diseases, as well as sufficient isolation wards. Isolation conditions, organic cooperation with random sampling surveys carried out by the disease control and public health systems, may be important roads to be explored and practiced in the future.
We ca n’t decide when and where the epidemic will break out, nor can we predict in what face it will come to us, but we can decide how to face it, whether to protect ourselves and family with a calm and rational mind, or in fear Sadness and anxiety in anxiety, or put yourself and others around you in danger in arrogance and fluke.
No one can stay out of the epidemic. In the fight against the epidemic, everyone is united, and everyone in their own positions gathers a small amount of strength into a huge wave that can overcome the virus.
The trauma and changes brought about by the epidemic may accompany us into the next decade. Some people lose their loved ones and friends, and grief and sorrow may accompany them all their lives; some people realize the preciousness of life after the rest of their lives, and they will rethink the relationship between man and nature; some people have an extra period in their memories The experience of running bravely to the front line, when you return home safely, and hug your loved ones again, a period of perception of life will be heard.
If we pass this epidemic, and through these more than 20 days of “depressed vacations”, we can develop good hygiene habits to protect ourselves, we can more rationally face the unexpected crisis, we can eliminate wild animal consumption and reduce the wild The infestation of animal habitats, then, this will be the most precious wealth left to mankind by this epidemic.