Where did the new virus come from

  From forests and farms to our own backyards, there are sources of disease, but there are many things we can do to reduce the risk of future pandemics.
  In November 2013, a previously healthy retired Saudi soldier was admitted to the intensive care unit of the local hospital due to fever and severe shortness of breath. Five days later, his daughter began to show symptoms of respiratory illness. Two weeks later, the retired soldier died.
   Soon, the researchers determined the cause of the disease. This 43-year-old Middle Eastern man raised 9 camels in a shed. Nucleic acid tests showed that he and the animals he raised were infected with a highly pathogenic coronavirus called Middle East Respiratory Syndrome (MERS-CoV for short) virus.
   When it was discovered that MERS-CoV can be transmitted from camels to humans, as well as from person to person, the alarm bell rang. This is the mysterious “Disease X”. Then, all countries received notifications one after another. MERS is a highly pathogenic disease with a fatality rate close to 50%. In the 7 years since its appearance, it has caused nearly 2,500 deaths in 27 countries. Currently, there is still no relevant vaccine or treatment in the world, and virologists worry that it will evolve into a more deadly disease.
   MERS and the current COVID-19 are just two of the many “zoon diseases” that have emerged in the past 50 years. These diseases can be transmitted from animals to humans. Experts say these are just harbingers of future trends. When the world is fighting COVID-19, virologists understand that more potential infectious diseases are waiting for us.
   Mankind will usher in a new wave of zoonotic diseases. Animals carry thousands of viruses, some of which are familiar to us, such as Ebola virus, Marburg virus and avian influenza virus. These viruses will continue to appear in unpredictable ways, and of course there will be some diseases that we do not yet know. The worst may not have come yet. Data from the Centers for Disease Control and Prevention (CDC) show that up to 60% of human infectious diseases are spread by animals, and 75% of new or emerging diseases are derived from animals, and these are almost all due to Triggered or worsened by human interference with the natural environment.
   The following are the top five sources of new infectious diseases occur in the future:
  from the forest
   at present, many serious diseases in the world, such as malaria, dengue fever, yellow fever, viral hemorrhagic fever, Urquiza that forest disease and West Nile fever, can be traced back History of deforestation on all continents.
   In places with high levels of biodiversity, such as tropical rain forests and tropical forest areas, there are more potential pathogens. However, through human activities such as road building and wild meat trade, we are destroying nature, continuously destroying the habitat of wild animals, and bringing wild animals into a situation where they have to have more intersections with humans. It is doubtful that it is we drove animals into a human environment that needs to barely maintain resources that allows the virus that exists in the wild animal environment to spread and make us sick. The troublesome thing is that we don’t know what other unknown viruses are or what is happening in many parts of the world.
   Bats are the host of Nipah virus and Hendra virus, and may also be the host of Ebola virus. Rena Pratt, a bat expert at the Bozeman Laboratory of Disease Ecology at Montana State University in the United States, has had to find new habitats due to the fragmentation and destruction of their habitats by human activities, and has increased the impact on humans. The dependence of the world was studied. She believes: “We need a global epidemic policy. Ecological security needs to be one of the principles of biosecurity. Efforts to protect the continuity of wildlife habitats and make every effort to limit our violations of existing species are imperative. ”
  from farm
   to wild animals in contact is not the only way to zoonotic diseases transmitted to humans. As the transmission route of MERS shows, livestock is also a problem. Salmonella, smallpox and measles are all thought to have originated from livestock. Today, with the development of intensive agriculture, this problem has become increasingly serious.
   In the past, camels were free range. Today, they are kept in sheds in the Middle East. Many camels are intensively kept together in captivity, leading to more contact between them and humans, and changes in breeding methods have brought more risks of disease transmission. It can be said that today’s feeding methods are leading to the emergence of new dangerous pathogens. It has been suggested that even if COVID-19 originally came from bats, it may be enhanced in a dense environment before it has a chance to enter the human body.
   In order to select better quality dairy cows, beef cattle and laying hens, humans usually keep these animal populations in dense environments, and their genes are very similar. This has laid a huge hidden danger for the emergence of diseases. These dense populations with the same genes are more susceptible to the virus, and the disease will spread quickly.
   The death rate of the Nipah virus that broke out in 1998 was 40% to 75%. At that time, the golden-crowned flying fox, the world’s largest bat, was deprived of its food source by humans and was forced to move to an industrial pig farm near Thailand’s orchard. Pigs that ate half of the golden-crowned flying fox and carried the virus-carrying fruit had almost no symptoms, but transmitted the virus to humans. As a result, millions of pigs were culled and more than 200 people died. Since then, Bangladesh and India have also discovered this disease.
   The Asian H5N1 virus originated in poultry farms and has so far caused more than 450 deaths, which is more than half of those infected. The intensive pig raising method is believed to have caused the pandemic of the H1N1 influenza (swine flu) that swept the world from 2009 to 2010, with an estimated death toll of 151,000 to 575,000 within a year.
   Jonathan Quick, Managing Director of Epidemic Response, Preparedness, and Prevention of the Rockefeller Foundation and author of The End of Epidemic, believes that as agriculture expands to virgin forests and meat production is increasingly industrialized, farms have become a zoonotic future. “Possible Pathways” of Infectious Diseases. He pointed out that factory farming is particularly prone to dangerous pathogens. Avian flu and swine flu are still part of the gamble we are playing arbitrarily in genetic roulette.
   At the same time, experts also expressed concern about the intensive breeding of wild animals. Nowadays, farmers no longer just raise traditional poultry and livestock. Humans have been partially immune to these animal diseases for centuries. At the same time, farmers have also raised hundreds of different animals for food and medicine, which are hidden dangers that may cause a large-scale epidemic. A study conducted by the Food and Agriculture Organization of the United Nations in Vietnam found that as many as 185 species of animals are now farmed everywhere, including ostriches, fruit bats, crocodiles, porcupines, flying foxes, turtles, crab-eating macaques, green pythons, civet cats, wild cats, and deer. , Snake, etc.
   For the pandemic, we need to transform from reactive and passive responses to forward-looking and active responses. We are losing too many species and too many natural landscapes. Now is the time for us to reflect and make new choices.
  From urban expansion
   in the rapid development and expansion of the city, animals and humans live closely together, there are more and more deadly disease might be transmitted to humans from animals.
   With the influx of large numbers of rural people into cities, the suburban areas surrounding most cities in developing countries have become dense areas for humans and animals. Diana Mitlin, the chief researcher of human settlements at the International Institute of Environment and Development, said: “Many people raise sheep and chickens there. The shallow wells are contaminated by animals, and sanitation facilities and garbage collection systems are lacking. Once an outbreak occurs in these areas, the disease will spread. It will be soon.”

   World Health Organization health director and professor of public health Jamie Bartram pointed out that urbanization may significantly increase the number of wild animals in the city, such as rats, foxes, skunks and possums. Poor sanitation facilities and contaminated drinking water have accelerated the spread of diseases in densely populated cities. Drinking water is important because it can spread pathogens between individual animals, between species, and between animals and humans. Zoonotic diseases transmitted through water can cause diseases such as diarrhea and hepatitis.
   The SARS epidemic in 2002 was one of the most serious zoonotic events in recent years. That year, a person from a chicken farm was infected with a previously unknown coronavirus pathogen, the virus later known as SARS (SARS). After the person brought the virus into Hong Kong, he lived in a dense apartment building called “Amoy Gardens”. Rats and cockroaches spread the virus through the sewer and pipeline system. More than 320 people were infected, of which 33 were Died before the epidemic was brought under control.
   SARS may spread all over the world, but it eventually spread to 29 countries and caused 774 deaths. The world has escaped SARS. This epidemic is not too bad for most parts of the world. This is a warning sign, but we have not learned from it. The SARS incident shows how vulnerable cities are and how easily people are exposed to deadly pandemic diseases. We have always ignored the risk of disease transmission in cities. The drainage and water supply systems located underground in cities are connecting one city to another city and the food chain through rivers. Diseases are also spreading through the flow of groundwater. In this regard, the researchers believe that the way to reduce risk is to increase infrastructure investment so that everyone can obtain safe drinking water and use clean toilets.
  From the pet
   and pet the number of companion animals and humans live together surge is one of the reasons leading to the spread of new diseases apart in the region. In the United States alone, two-thirds of households have pets, and more and more households are raising various wild animals, including snakes, hamsters, hedgehogs, birds, and ferrets. These pets may be the source of serious epidemic outbreaks. The improvement of modern people’s living standards has led to an increase in the number of pets that people keep, which has become a potential hazard to trigger the outbreak of new diseases.
   The exponential growth of humans has to invade the natural habitats of wild animals more and be more exposed to pathogens that infect wild animals. Domesticated animals can also be spreaders of these pathogens, such as golden-crowned flying foxes infected with Nipah virus and horses infected with Hendra virus. In some Middle Eastern countries, it has become a fashion for people to keep some rare carnivores as pets. The release of movies such as “Jurassic Park” has led to an increase in the possession of reptiles such as iguanas, which are regarded as the incarnation of dinosaurs. Most reptiles are natural carriers of Salmonella and can easily spread the bacteria. Diseases such as meningitis, monkeypox and American trypanosomiasis are sometimes transmitted from pets to humans. There are also birds, reptiles and rodents that usually carry salmonella. In addition, hamsters also carry a virus that can cause neurological diseases.
   As for the response, supervision is the key factor. Local health departments should force the establishment of veterinary public health units to better control zoonotic pathogens, especially new pathogens from farm animals and pets, and regulate wildlife trading and bush meat markets.
  From human error
   when assessing the possible future epidemics, human error should be taken seriously is a problem.
   Research projects in the laboratory cannot overcome human error or insufficient training. Although accidents are extremely rare, the possibility of them always exists. The danger may come from a culture in the laboratory or an individual. Most researchers study pathogens with low epidemic potential, so there is no great risk of transmission. But it is undeniable that some of them are studying very dangerous pathogens.
   In the UK, some man-made accidents have led to the release of smallpox and foot-and-mouth disease viruses. In the United States, all kinds of viruses, such as Ebola virus and avian influenza virus, escaped from the laboratory of the Centers for Disease Control. Marburg virus was infected and spread when German laboratory workers came into contact with the virus from monkeys transported from Uganda.
   Laboratory accidents can cause disease to spread to communities outside the laboratory, and infected laboratory personnel will leave with pathogens when they leave work. Lynn Klotz, a senior scientific researcher at the U.S. Center for Arms Control and Non-Proliferation, wrote in an article: “If the pathogen involved is a potential pandemic pathogen, the escape of the pathogen may lead to a global pandemic. The epidemic caused many deaths.”
   Strategies to reduce risk include ensuring compliance with standard safe operating procedures, reporting laboratory waste disposal regulations and infections. What is worrying is also the mistakes related to risk assessment. The main researchers should make correct judgments on the risks involved in the specific research experiments they conduct.
   In summary, in any case, investment in the public health system is essential. All epidemics stem from weak health systems. We may have all the medicines and knowledge to cure patients, but if we do not build a strong health system, we will continue to see epidemics cause unnecessary losses while destroying the economy. To ensure the health and safety of the people and the prosperity of the country, what we have to do is to prevent all crises instead of passively responding to one public health crisis after another