Pigs coughing so loudly that the noise is heard over a kilometer away from the pigsties. Dozens of gorilla bodies accumulated in a remote corner of the forest, while the rest of the forest, once filled with these great apes, becomes a void. Agitated horses, salivating foam and blood, which die after a few hours of agony.
These and other horror stories, narrated in the book “Contágio”, by the American writer David Quammen, are different in details, but a common thread unites them: they all begin when a previously unknown virus jumps out of a species (as a rule, the one that functioned as a natural reservoir of the parasite) for another, with potentially catastrophic consequences.
The same phenomenon, known as “spillover” (something like “overflow” in English) was responsible for producing the current Covid-19 pandemic, whose cause, the Sars-CoV-2 virus, probably originated in Asian bats and managed to adapt to the human organism.
In fact, Quammen, 72, was certainly not surprised to learn of the identity of the new pandemic virus. Originally released in 2012, his book already spoke of the importance of bats as viral reservoirs and the role of respiratory viruses in pandemics throughout history.
For now, the publisher Companhia das Letras is launching Quammen's work in parts, in electronic format. Two "issues" have already been published: "Dinner at the Rats Farm" (on the coronavirus that causes respiratory disease Sars) and "Everything Depends: Human Behavior and Pandemics". Two more parts are expected to hit e-book stores by the end of May. The plan is to publish the entire book later this year.
Quammen talked to Folha about the difficulty of stopping wild animal trafficking, which puts both animals and humans at risk, and about the role of industrialized livestock in enhancing the problem.
Asked about the mysteries related to the origin of epidemics in animals that have not yet been well elucidated, the writer replied: "Perhaps the biggest mystery is that we still elect leaders like Trump and Bolsonaro".
In the past decade, mr. he was in Chinese restaurants where the most varied species of wild animals were served. Many people already knew of the link between these restaurants, the “wet markets” that sell live animals and previous epidemics, such as Sars, but even so, Sars-CoV-2 ended up emerging. Why is it so difficult to eliminate this type of trade?
I intend to visit China to try to investigate this personally, but the most reasonable answer is that a lot of money is flowing into that market. There is still a very busy trade in pangolins (animal that carries forms of coronavirus similar to the current pandemic), which are threatened with extinction and are taken from Malaysia to China, for example.
Since 2003, when there was the original SARS outbreak, the Chinese tried to suppress this trade, but it ended up becoming a black market and, later, it was again practiced in the open. In 2009, when I visited the country, you didn't see wild mammals, like civets (small carnivores that resemble felines) or porcupines, being sold in the open, but it was still possible to obtain this type of meat in a truck that stopped at a certain place at night or through the back door of a restaurant.
On the other hand, when we hear about these “wet markets”, we must remember that many people buy chickens, ducks and seafood in them, a type of trade that is completely legitimate and has nothing to do with animal trafficking.
This means that the negative consequences of calling Sars-CoV-2 the “Chinese virus” and reinforcing the stigma surrounding practices in eastern countries may end up increasing the risks of future pandemics, as there is an incentive for there to be less transparency about these problems?
Yes, it is something that does more harm than good. It doesn't help to talk about the “Chinese virus” or the “Wuhan virus”. In 1918, instead of talking about the “Kansas flu”, the place where the pandemic started in the USA, the term that caught on was “Spanish flu”, In fact quite misleading. What we need to understand is that these diseases are part of a much broader pattern.
When any of us consumes meat, wood, fossil fuels or strategic minerals, we are putting natural ecosystems under pressure and increasing the likelihood that a dangerous virus will reach humans. Just have a cell phone. The devices we use contain metals obtained from coltan, a mineral found in eastern Democratic Republic of Congo. Coltane mining causes many people to end up in contact with animals that are reservoirs of the Ebola virus, or other potentially lethal viruses.
People are already arguing that it is best to let Sars-CoV-2 spread as quickly as possible because this will favor the appearance of less dangerous strains. According to them, the virus, to adapt to new human hosts, will avoid causing serious damage. There is no guarantee that the process will work that way, right?
It is an idea that has no support, neither from a historical point of view nor from a scientific point of view.
In the book, I recount what happened to the myxomatosis virus, which affects rabbits and was used to try to control the population of these animals in Australia. The mortality it causes has stabilized at around 70% even after decades of evolution.
In the case of a virus like the current pandemic, if you do nothing to try to slow transmission, what will happen is that there will be no pressure for it to evolve, since it will be able to spread very successfully. And, in fact, this is what we are seeing for now: there are no signs of molecular evolution of the coronavirus, which shows how successful it has been.
Is it possible to say that the riskiest events involving the emergence of new pathogens are those linked to wild species? Or can industrial animal husbandry be as risky as the trade in wild mammals?
I don't know if it is possible to say that the risk is the same, but raising animals on an industrial scale is certainly part of the problem. We know that it is the source of many dangerous viruses, such as Nipah (which emerged in Malaysia in 1998, killing 105 people and leading to the slaughter of 1 million pigs) and the 1918 flu itself, both linked to swine hosts.
By raising animals in immense concentrations of individuals, we are doing the equivalent of accumulating large amounts of wood and dry leaves in a forest. It is a fuel capable of starting a forest fire with great speed if the circumstances are favorable for that.
What are the mysteries about the origin of epidemics in animals that have not yet been elucidated?
We will always have a lot to learn from these events, but I think that there is not exactly any deep scientific mystery on the subject that has not yet been elucidated. Probably the most important point has to do with the goal of stopping these contagions between animals and humans before they turn into epidemics and pandemics. And that will depend on scientific, technological and international cooperation advances that have not yet happened.
In the book I mention, for example, a researcher who was trying to develop systems capable of accurately detecting who is carrying a new virus during a routine check at an airport, something that could be resolved in ten minutes. We don't have that yet, which probably has to do with a lack of funding. Perhaps the biggest mystery is that we still elect leaders like Trump and Bolsonaro.
There is much speculation about how the current pandemic is going to change the world. In your opinion, is it possible to hope that people will finally understand that environmental destruction is the main mechanism behind the emergence of new lethal viruses?
I think so, for the simple fact that horror, death and – sad to say, but true – the cash cost of what is going to be going to be very difficult to ignore.
Here in the USA, for example, the government is spending $ 3 trillion in aid to businesses and workers. It is immensely expensive. Being prepared to face a pandemic is expensive, and myopia political leaders may feel that it is not worth spending on when there is a chance that nothing will happen during their term, but what we are seeing is that the cost of not being prepared is absurdly higher.
David Quammen, 72, was born in 1948 in the United States and studied at Yale and Oxford. He wrote some fiction books before dedicating himself to the natural world. "Contágio", launched in 2012, was a finalist of seven awards and received two of them: Science and Society Book Award, from the National Association of Science Writers, and the Society of Biology (United Kingdom) Book Award in General Biology. He contributed to National Geographic magazine and was a professor at Montana State University.