Covid-19: Origins of an outbreak

When we looked at emerging infectious diseases like Cova 19 for decades, we recognized about three per year. In this last decade, that is, up to five per year, we know that in viral families that are known to cause human diseases and are shared with others. animals that there are still at least five thousand viruses to be discovered that can infect us and make us sick, so we have only scratched the surface, now we are going to remote areas that have viruses that have been there for millennia but that people If we have not been exposed to them, we are exposing ourselves to things that are simply not in our evolutionary history and we are really at risk.

A zoonotic disease is a disease caused by a pathogen that is shared between animals and people, so whatever. that we might contract because we interact with an animal or interact with people who have interacted with an animal, especially those animals that we have not interacted with throughout our evolutionary history, that is the perfect circumstance for us to contract a new disease, but the Zoonotic diseases are not new, the most famous is rabies. There are many diseases that are now primarily human-to-human and that were originally zoonotic diseases such as HIV, AIDS and flu, that we deal with every year.

At first they were a zoonotic disease and it is from human to human, but every now and then we incorporate new genetic material and we get remixes of birds, pigs, horses and all kinds of other species that are also susceptible to the flu, so the Zoonotic diseases are much more common than people think, but in reality they are those that come from wildlife that surprise us sars kobe 2 has the equipment to be a jumper, we say jumper, so it jumps species and the more species and the broader range of species that a virus can jump to, the more we worry about it having an epidemic and a pandemic. potential and so this at first was only in people as far as we knew and we could use science to say that the suspect where it evolved from is most likely a bat, just given all the probabilities and what we know about it , there were certain types. of bat hosts that were almost certainly the original evolutionary hosts of this virus, so we were able to intervene very quickly and say, "Hey, if you know the distribution of those hosts, you can start to understand where the virus may have originally spread." and if there is a new strain, it may be that migrating animals brought it to multiple areas.

There is a lot of scientific discussion about a contagion event from a bat to an intermediate host or another animal before it can become infected with people and we know this with the first SARS. That's believed to be the case, that there were bats whose pathogens mixed and spilled into civets, which is an interesting carnivorous creature that's also sold in markets and then people got exposed to those civets and that's probably true, but it's all based on circumstantial evidence months after the actual spill, so this is probably what will happen with sars coronavirus 2. There will be a lot of information that will come to light for decades and we will be able to piece some things together. to understand what really happened, but now we know that you don't need that intermediate host to collect and get the additional equipment on the virus to then get into people.

We were able to discover that before sars kobe 2 occurred, that the bat Humans are also a direct possibility. Bats are really interesting, they have some really interesting evolutionary mechanisms that probably make them better vessels for holding viruses and being a source for us and other species. One of them is that they fly long distances, so they sample many different areas. and then they can spread out into a lot of different areas, another one has a lot more to do with their metabolism and their immune system, they actually evolve to fly and we think there are some really interesting mechanisms that allow them to have much higher body temperatures and be able to function and not get sick, that also allows the viruses to be there and evolve, whereas in a person you can have a fever and fight it, and we study those flying things a little less than we study dogs, cats and cows, so it makes us feel scientifically that we are going to find a lot of things in bats, but it's also worrying because we've spent so much less time in scientific history doing that work, one of the first species where we recognized that it was actually spilling over from people.

They were cats, so people's cats were in their homes first and foremost, but then we saw big cats like tigers and leopards in zoos, and then by looking at dogs, we could see that dogs could become infected over time. We saw people infecting mink on mink farms in Europe and in North America and I saw that mink were very likely to be a very good host and there was a tragic depopulation of large numbers of mink because our white-tailed deer population in The US seems to be infected, we hope the people have won. I don't interact with them in a way that exposes them, but that possibility certainly exists.

I want to be clear that it is not animals that put people at risk, it is our human behavior and the risky things we do that put ourselves at risk of exposure. these viruses don't jump out and catch us, for example, we go to caves and mines in places that were previously uninhabited why get us things to lighten our mobile phones and everyone has the right to a mobile phone and that's how we do it we are using the planet instead of living with the planet in balance is also causing that change. This is especially important for the Amazon rainforest because we know that most undetected coronaviruses should be due to hosts harbored in the Amazon, and yet what are they? what we are doing, we are destroying the Amazon, harming our own ability to get oxygen and keep our planet at the right temperature and at the same time causing an extreme risk of spill because it is in those buffer areas where we are transitioning between environments where we see these spills.

This is happening more frequently, so it's human population growth, land use change, we're going more and more to more remote areas, we're going there more frequently and more destructively, we're going there in large numbers. quantities and we bring our pets with us. because we need food and those viruses can spread to them and amplify and change before they reach people, we are talking about the interconnected health of the entire planet, the people, the animals, the environment and when we protect that, we protect ourselves. ourselves. longer term