The annual poultry meat production has increased from 9 to 122 million tonnes worldwide between the 1960s and today; eggs from 15 million to 87 million; the number of chickens, from just under 4,000 to 20 billion. But chicken farms can also be a “weapon of mass destruction,” says veterinarian David Waltner-Toews, and all because new and “emerging” pandemics, this time in the mouths of fellow veterinarian and epidemiologist Luis Martin Otero, today almost always have their origin in animals.
Are they exaggerating?
Come in and read.
H5N1, better known as avian influenza, and previously mad cow disease, would have done nothing but warn of it in the 1990s. The numbers speak for themselves: “More than 65% of the agents that infect humans come from animals. And this percentage has increased in the last 30 years”, explains Pedro Arcos, epidemiologist, director of the unit on Emergencies and Disasters at the University of Oviedo and former president of Doctors without Borders in Spain (MSF).
The data confirms this.
Since the middle of the twentieth century, zoonotic diseases, that jump from species to species and among them to humans, have not stopped growing, until multiplying threefold, with the consequent “risk of epidemic or pandemic, especially if these are new, if they have recently jumped from an animal to man and if they are transmitted by air”, Arcos continues. It was cited in an article in the journal Nature in 2008 and reaffirmed in the last decade, especially by the most current and global health crisis, Covid-19.
And the SARS-CoV-2 coronavirus is still unknown, which animal made the leap to the first affected by this disease in China. Was it the pangolin? Or the bat? Maybe another one? Whatever it was, this virus already joins the other illustrious names of zoonosis; those that not only sound to us, but are feared.
There is the string of diseases, among which Ebola, yellow fever or rabies stand out. Even with a lower epidemiological capacity, trichinosis, salmonellosis, tuberculosis, brucellosis or toxoplasmosis, for example. But there is more. There are viruses, bacteria, fungi, parasites, and even simple protein fragments like prions. They all have an animal origin. And they all have humans as their targets. 75% of emerging diseases and among them is added to HIV, have animal origin according to the Spanish College of Veterinarians.
Fear, however, is on your plate.
The first alarm went off with beef in the 1990s. Mad cow disease could be contracted by eating beef. So far there have been around 200 people affected. And thousands of cattle have been slaughtered.
Luis Martin Otero
The danger of a global epidemic also rang out in the late 1990s, in 1997, when healthy people started to get sick in Hong Kong from consuming chicken meat. It was a shock to virologists: a virus that previously only infected birds, H5N1, had made the leap to humans. It has had between one and two hundred victims, mainly in Asia. H5N1, compared to the current Covid-19, however, has a very high mortality rate of almost 50% of those infected.
And who does not eat chicken in the world?
It is basic in most vegetarian diets such as those in India, Latin America, the Far East and in the healthiest, as well as industrial, food in western countries. It is the reason why the meat of slaughter animals, of species that are treated industrially for subsequent human consumption, has continued to grow and grow on a global scale.
Manuela Castillo, professor of agricultural economics at the University of Cordoba, shows us the scale: “In general, farms grow in size over time through a classic process of restructuring: owners who abandon production (older without generational replacement) and small farms), freeing up land for other farms. In intensive livestock farming, on the other hand, since land is not a restriction on business growth, there has been an increase that has especially occurred in pig farms,” she points out.
Here is the danger: “When animals are mass produced in an industrial way, although the process is done rigorously from a hygienic-sanitary point of view, there is an increased risk of zoonosis, simply due to an aggregation phenomenon. We could say that small farms have outbreaks, large farms have epidemics, and in the processes of mass production, there is a greater risk of causing pandemics by zoonotic agents,” says Arcos.
Aragon, for example, sacrificed almost 100,000 minks from a farm this July. 87% of those analyzed tested positive for the SARS-CoV-2 coronavirus. Also seven workers. The order of transmission, from animals to humans or vice versa, is still unclear.
But there is more. And the warning sounds again.
Another fear is the consequences on a global scale: large-scale food production involves greater risk because as experts repeat, food produced on a large scale usually has a global or almost global distribution that may require a chain of cold and the control of distribution, conservation and sale in very diverse places and with a very large and dispersed group of potentially exposed consumers.
“The larger the process, the greater the risks,” Arcos says. And Martín Otero, coordinator of the Spanish Network of Biological Alert Laboratories of the Ministry of Science, Innovation and Universities at the Veterinary Health Surveillance Center of the Complutense University of Madrid, adds: “Veterinary control is to prevent and control it, but spaces such as avian eggs, with heat and for their amount of proteins, are a breeding ground for viruses… It’s a health and manipulation problem. Although the industry here is very controlled. Another thing is to get into habitats that are alien to us, with diseases restricted in spaces, until now, not accessible. We’re going to places that don’t belong to us,” he concludes.
Precisely because the global world seems difficult to stop, the World Health Organization together with the FAO and the International Organization for Animal Health have organized an international system for epidemiological surveillance of zoonoses. And there have been initiatives like OneHealth, to control animal health in pursuit of human health because both are “one health.”
However, several international consortia have been working for years to prepare for the so-called disease X, the next to produce a pandemic. Covid-19 is now this disease, but due to a history of other coronaviruses, more have long been anticipated.