The coronavirus outbreaks, including the severe acute respiratory syndrome (SARS), the Middle East respiratory syndrome (MERS), and the currently spreading coronavirus disease (COVID-19), all came via animal-to-human transmission or zoonosis.
Zoonosis is any disease or infection that is naturally transmissible from animals to humans, which may be bacterial, viral, or parasitic.
Now, a University of Oxford scientist, who is working on a candidate vaccine against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), warns of an increased risk of outbreaks spreading from animals to people.
Increased threat of future outbreaks
Professor Sarah Gilbert said that human activity, such as urbanization and globalization, is driving the increasing threat. Animals start to live near communities and residential areas, while some animals are forced out of their habitats due to the continuous use of land for industrial and agricultural needs.
"Greater population density, greater travel, deforestation – all of these things make it more likely that these outbreaks will happen, and then something will spread," Gilbert said in a statement.
The warning comes after a mutated strain of coronavirus, which is ten times more infectious, was detected in Indonesia, as well as nearby countries like Malaysia and Singapore. The spread of SARS-CoV-2, the virus that causes COVID-19, has impacted economies and livelihood and overwhelmed health systems around the world.
Source of SARS-CoV-2
Until now, it is still unclear where the SARS-CoV-2 came from, but data shows that it came from an animal origin. Coronaviruses are known to thrive in bats found in jungles across the globe. From bats, the virus may transfer to intermediate hosts, such as camels, pangolins, palm civets, and raccoon dogs.
Horseshoe Bat (Rhinolophus affinis). Image Credit: Binturong-tonoscarpe / Shutterstock
In the coronavirus pandemic spreading across the globe, scientists point to pangolins as potential intermediate hosts. Further, the SARS-CoV-2 outbreak first emerged in a seafood market in Wuhan City, where wild animals are sold.
The presence of the virus in the intermediate host could have been a short-term event. If the virus jumped from a bat to another animal and from the animal to humans, there is no guarantee the virus is still circulating in the animal population. However, if the cycle repeats itself in the future, there is a considerable possibility of another coronavirus outbreak, which may be akin to what is happening to the world today, or worse.
Pangolins from smuggling are secured at the Natural Resources Conservation Center Riau, Pekanbaru, Indonesia, Wednesday. Image Credit: Arief Budi Kusuma / Shutterstock
Causes of zoonosis
In July, the International Livestock Research Institute (ILRI) in the United Kingdom has reported seven trends driving the increasing emergence of zoonotic diseases, including the increasing demand for animal protein, climate change crisis, and the unsustainable farming practices, among others.
The report also reveals ten practical steps that countries can do to reduce the risk of future coronavirus outbreaks, which include improved regulation of food systems, expanded research on zoonotic diseases, and incentivizing sustainable land management practices.
"The science is clear that if we keep exploiting wildlife and destroying our ecosystems, then we can expect to see a steady stream of these diseases jumping from animals to humans in the years ahead," Inger Andersen, UNEP Executive Director, said.
"Pandemics are devastating to our lives and our economies, and as we have seen over the past months, it is the poorest and the most vulnerable who suffer the most. To prevent future outbreaks, we must become much more deliberate about protecting our natural environment," he added.
Global toll
The coronavirus pandemic has now infected more than 25.59 million people and has killed at least 852,000. The hardest-hit countries include the United States, with more than 6 million confirmed cases and more than 184,000 deaths, and Brazil, with more than 3.90 million cases and a death toll reaching 122,000.
The other countries with high case tolls include India, with more than 3.69 million cases, Russia, with more than 997,000 cases, Peru, with more than 652,000, and South Africa, with more than 628,000.
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