The COVID-19 pandemic is devastating the world starting with a simple virus that infects animals. The virus that can jump from animal to person like this is called zoonotic virus. They cause up to 75% of all emerging diseases in humans, and are one of the most important research areas when it comes to public health.
Epidemiologist Christine Kreuder Johnson knows that any strain of virus that infects wildlife, anywhere, even in remote parts of the world, has the potential to threaten health. of all humanity.
She is currently studying the process of zoonotic virus spill over into human populations as associate director of the One Health Institute of the University of California, Davis.
One Health is a multidisciplinary and interdisciplinary method of cooperation from local, regional, national and global levels to ensure human health in an inseparable harmony with animal health , plants and the habitat of all.
Epidemiologist Christine Kreuder Johnson
Johnson was the lead author of a new study that discovered that domesticated animals, along with wild animals, have to adapt to invasion of human habitats – typically bats and rodents such as mice – are responsible for the majority of zoonotic viruses that cause disease in humans.
These results are evidence that human influences on animals can have serious consequences for our own health.
The study was funded through USAID’s Emerging Threat Prediction program. Since 2009, the program has collected more than 140,000 biological specimens from animals, allowing scientists to identify 1,200 viruses – including more than 140 corona virus strains – in the future that could pose threats. global threat similar to COVID-19.
The Verge had an interview with Johnson to talk about the ongoing pandemic, and what we can do to prevent the occurrence of such pandemics in the future.
Here are the answers from Christine Kreuder Johnson:
What are zoonotic viruses and what makes them especially dangerous?
Johnson: Some zoonotic virus strains are not dangerous. Many of these are endemic, but are only endemic strains (infecting certain species, within a certain geographic area).
Zoonotic virus mostly affects only those who come into contact with animals – especially farmers.
But the new corona virus has taken a leap from animals to humans and can be transmitted from person to person. Because it is derived from animals, all human beings are susceptible subjects. Because we have never been exposed to them before and have not built immunity to this strain.
That is why the new corona virus is especially dangerous. When they are transmitted from person to person, and everyone comes into contact with them for the first time, we will all get sick at the same time.
And as you can see, that is a huge burden on public health resources and health care facilities, which now has a large number of patients at the same time. Things can go quite tragic according to that scenario.
How do scientists study or monitor viruses in wildlife?
They do it very, very carefully. I can say it with all my heart, because I myself am honored to be working on the PREDICT project (a multinational project kicked off by the United States Agency for International Development (USAID) for early detection of infectious diseases that could threaten human health) with colleagues in countries of Africa, Asia and Latin America.
For the most part, they are wildlife veterinarians – one of the best ambassadors to help us find safe, effective and especially humane ways to work with wildlife. We must be careful not to increase the risk of disease.
As part of the PREDICT project, we all agree with a basic principle that we will leave no ecological footprint. We will capture animals, collect samples from them, and release them immediately.
We take gauze. We also take a blood sample so we can find the virus. But antlers are the best way to collect corona virus. And we will ensure absolute biosecurity in doing so.
These are pictures of us wearing protective clothing with a mask, face shield and white Tyvek set. That’s how we sample to make sure we don’t put health workers at risk.
And in addition, there is another risk in which we spread human pathogens to animals. Therefore, we must ensure that we do not upset the balance through our operations.
How can zoonotic viruses infect humans?
We are sharing habitat with animals, just as our ancestors have shared it before. In doing so, we have the opportunity to interact with animals when their habitats interfere closer to the human community.
Many viruses are likely to be shared through contact with faeces or urine or other pathways when we live with these animal populations.
It is very important to consider how human actions are changing the level and amount of animal encounters. We have fairly clear evidence that when the habitats of these animals are disturbed, they will have a higher demand for movement and the disease will become stronger in their own populations.
Like the situation we encounter now, when a pandemic breaks out, we are asked to stay at home and stay where we are. Because it’s clear that if we continue to move around, we increase the risk of outbreaks of this disease.
Similar disease dynamics occur in wildlife populations. When wildlife is hunted or their habitat is destroyed, they have to move. That movement actually increases disease dynamics and increases the likelihood of disease occurring in both animal and human populations.
In the markets, you have a lot of different wildlife species like bats, predators and ungulates. Those different animals are gathered together and they are still alive, so they can share the virus with each other.
The ability of viruses to jump from one species to another is very difficult and rarely occurs in nature, but we humans are creating opportunities for viruses to mutate so they can jump to other species near them.
Animals share respiratory droplets or urine and faeces containing pathogens. By creating environments with a dense population of animals, we increase the chance for one of those mutations to occur.
And then, we put people in the same situation again, (in the markets) where there are often so many people close together, so it creates a kind of perfect epidemiological situation for the virus to jump out of. host and try to escape to a new host.
What can we do to minimize the risk of future pandemics?
There are many things that can be done to manage wildlife trade. But I also think we still have to find a safer way to live with these animals.
We really need to care about the health of wildlife populations, which is the last frontier. Of course, we have invested heavily in human health, which is necessary. After that, we have continued to invest heavily in caring for animals that are tamed for food safety needs, and because they are our pets.
But now the health of wildlife is considered the last secondary, because few people work in this area, it is often less invested, and if there is only investment from the government. We have learned a lot from that, but there are still many other things that need to be learned.
What is the health of animals and their habitat related to human health?
The current medical model has changed a bit, when we started to realize that animal health and human health are quite closely related, that are diseases that can be transmitted from animals. luxuries for humans.
We begin to implement many effective policies around surveillance of human and animal diseases, to ensure that these activities are more connected, scientific groups have reported and shared their work results. To each other, we have got more information.
But one idea that has been overlooked is that our health – and certainly the health of animal populations, especially wildlife – also depends heavily on habitat health and integrity of the ecosystem.
We have established areas such as public health and ecosystem conservation, and we have had many opportunities to discuss with the participation of many other areas to try to understand disease risks. in perfect way.
This is where One Health’s approach (multidisciplinary and transdisciplinary cooperation on many levels from local, regional, national to global to ensure human health in harmony with animal health , plants and our shared habitat) really makes sense.
One Health shows us that animal health and human health are closely linked and intertwined. And then, we also need to think that the health of the environment is really the core of both. Human health is essentially the health of the environment.