Why don't we know what animal COVID-19 came from?
Why don't we know what animal COVID-19 came from?
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While scientists have hypothesized that COVID-19 came from snakes, pangolins, bats, and other creatures, we still don't know exactly which animal passed the virus to humans, or how many species it might have impacted along the way. Scientists have determined that the virus did come from animals, not humans, and was first traced to a wet market in Wuhan, China. Many countries are hoping an independent investigation will take place to determine when and how COVID-19 first entered the human population, and at exactly what location. Many experts believe that the virus is a "wild" one, meaning that one animal species transmitted the virus to another species before it was spread to humans. The only way to determine exactly which animal the virus came from is to find the original animal species in the wild.
While scientists have hypothesized that COVID-19 came from snakes, pangolins, bats, and other creatures, we still don't know exactly which animal passed the virus to humans, or how many species it might have impacted along the way. Scientists have determined that the virus did come from animals, not humans, and was first traced to a wet market in Wuhan, China. Many countries are hoping an independent investigation will take place to determine when and how COVID-19 first entered the human population, and at exactly what location. Many experts believe that the virus is a "wild" one, meaning that one animal species transmitted the virus to another species before it was spread to humans. The only way to determine exactly which animal the virus came from is to find the original animal species in the wild.
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What our experts say
While scientists have hypothesized that COVID-19 came from snakes, pangolins, bats, and other creatures, we still don't know exactly which animal passed the virus to humans, or how many species it might have impacted along the way. Scientists have determined that the virus did come from animals, not humans, and was first traced to a wet market in Wuhan, China. Many countries are hoping an independent investigation will take place to determine when and how COVID-19 first entered the human population, and at exactly what location. Many experts believe that the virus is a "wild" one, meaning that one animal species transmitted the virus to another species before it was spread to humans. The only way to determine exactly which animal the virus came from is to find the original animal species in the wild.
While scientists have hypothesized that COVID-19 came from snakes, pangolins, bats, and other creatures, we still don't know exactly which animal passed the virus to humans, or how many species it might have impacted along the way. Scientists have determined that the virus did come from animals, not humans, and was first traced to a wet market in Wuhan, China. Many countries are hoping an independent investigation will take place to determine when and how COVID-19 first entered the human population, and at exactly what location. Many experts believe that the virus is a "wild" one, meaning that one animal species transmitted the virus to another species before it was spread to humans. The only way to determine exactly which animal the virus came from is to find the original animal species in the wild.
Context and background
Most disease-causing agents, such as viruses and bacteria, stay within one host species, with many barriers preventing a jump from animals to humans. When a disease does break down the barriers between animals and people, it’s called a zoonotic disease. It's rare to have that jump result in a global outbreak, but even more rare to result in a global pandemic, as we're experiencing now. These jumps are becoming more commonplace, likely due to climate change. According to Margaret Wild, an expert in wildlife diseases and a professor at Washington State University in the U.S., “These diseases don’t transmit to humans often, and when they do, it’s typically when we push natural systems by destroying animal habitat or crowding different species together with people in a marketplace.”
Most disease-causing agents, such as viruses and bacteria, stay within one host species, with many barriers preventing a jump from animals to humans. When a disease does break down the barriers between animals and people, it’s called a zoonotic disease. It's rare to have that jump result in a global outbreak, but even more rare to result in a global pandemic, as we're experiencing now. These jumps are becoming more commonplace, likely due to climate change. According to Margaret Wild, an expert in wildlife diseases and a professor at Washington State University in the U.S., “These diseases don’t transmit to humans often, and when they do, it’s typically when we push natural systems by destroying animal habitat or crowding different species together with people in a marketplace.”
Resources
- First Reported Cases of SARS-CoV-2 Infection in Companion Animals (U.S. CDC)
- Coronavirus: A hunt for the 'missing link' host species (BBC)
- Virus Mutations Reveal How COVID-19 Really Spread (Scientific American)
- Animal source of the coronavirus continues to elude scientists (Nature)
- Infection of bat and human intestinal organoids by SARS-CoV-2 (Nature)
- Explainer: What we know about the origins of the coronavirus pandemic (Reuters)
- SARS-CoV-2 in animals (AVMA)
- Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China (The Lancet)
- Genomic variations of COVID-19 suggest multiple outbreak sources of transmission (medRxiv)
- First Reported Cases of SARS-CoV-2 Infection in Companion Animals (U.S. CDC)
- Coronavirus: A hunt for the 'missing link' host species (BBC)
- Virus Mutations Reveal How COVID-19 Really Spread (Scientific American)
- Animal source of the coronavirus continues to elude scientists (Nature)
- Infection of bat and human intestinal organoids by SARS-CoV-2 (Nature)
- Explainer: What we know about the origins of the coronavirus pandemic (Reuters)
- SARS-CoV-2 in animals (AVMA)
- Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China (The Lancet)
- Genomic variations of COVID-19 suggest multiple outbreak sources of transmission (medRxiv)
