Man pays an expensive price for agriculture that replaces the hunter-gatherer lifestyle: we got most of our devastating diseases from the bipeds and quadrupeds that live with us.
Exactly what kind of goods and in what way the coronavirus released in China was transmitted to humans from the bat of its original owner is still being studied by scientists, but they have known (or suspect) for at least a century that one of the the greatest risk – and if we are talking about an epidemic risk – is clearly the greatest – is human-animal coexistence. In order for diseases to decimate the population of countries and continents (sometimes halving throughout history) to emerge from this theoretical threat, the migration must be lasting and the relationship must be close: news of our hunters -the murderous whims of livestock peoples because they did not live, literally or figuratively, under one roof with farm and companion animals.
When an unknown disease on the west coast of the U.S. began taking victims among injecting drug users and homosexuals in the early 1980s, no one probably suspected that genetic traces of infection of unknown origin would lead to the Congolese rainforest. We now know that the HIV virus was of West and Central African nationality, originally a disease of apes, and sometime in the twentieth century. it may have been transferred to man at the beginning of the 19th century.
To cross the line that separates chimpanzees from humans, it had to mutate, but until it spread from person to person, it only caused sporadic diseases. It took one or more new mutations to form an order of magnitude more dangerous human-to-human version: with this innovation, the virus allowed itself to conquer the entire planet.
Animal-to-human infections are collectively referred to as zoonoses, and according to media reports, coronavirus epidemics in the fairway can tell many that SARS, Ebola, H1N1, and the current coronavirus epidemic itself belong to this broader group. It is less common to say that this particular group of diseases is by no means so narrow, and it is not at all limited to the contagions discovered in recent decades. Leprosy, for example – according to Balázs Horváth, the author of the basic work Earth and Human History – The Sick Planet – was obtained from the water buffalo, which had been a partner for about 6,000 years, according to some sources. The buffalo was originally a semi-wild, open-air animal of nomadic, nomadic peoples — it could only pass the infection on to humans later, at the time of the establishment of the settled farming society. This is because successful zoonosis usually requires long-term and close coexistence, in most cases known so far, where the pathogen is provided not only with passage, but also with time for multiple mutations.
Of animal origin, viral measles, TB, TB, smallpox, malaria, whooping cough, cholera, plague – a total of more than 50 serious infectious diseases. The relatively high number alone indicates that there is more to it than just chance. The explanation may be that the original viral and bacterial hosts were already large-group, mass-occurring animals prior to domestication, providing a suitable environment for the selection of pathogens capable of rapidly infecting large populations. In their case, we can speak of many thousands or tens of thousands of years of human-animal coexistence, but this is only a moment on an evolutionary scale – too little time for us to develop protection (just as we are not protected against many diseases that can be contracted from dogs, even though humans and the wolf (the ancestor of every dog today) has a common past of more than 100,000 years, according to recent sources.
H1N1 avian influenza has also become a threat to humans where (in Asia) huge poultry farms are barely physically separated from human habitats.
There is also a reason why we are encountering new zoonoses more often these days: the destructive effects of man himself and human civilization. Climate change is changing the distribution of some species, allowing certain animal species to encounter many more humans or new human populations; settlements invade previously untouched natural areas, and man – through the trade of exotic animal species, or even the encounter of many rare (and not originally sought for food) animal species with each other and with animal markets that used to consume animals that were previously taboo and provides additional opportunities to encounter exotic viruses, including their mutation. Meanwhile, we are constantly stuffing the environment with knowingly mutagenic, i.e. mutation-promoting, chemicals, and many man-made changes (increased radiation, or even stronger UV radiation due to damage to the ozone shield) have such consequences.
The result of these effects, if only according to the rules of mathematics, is the increase in animal-to-human and then human-to-human epidemics: not death every few years due to a zoonosis in Africa, Asia or the world, but the fact that these epidemics are still relatively rare despite the conditions that are favorable to them.