Four out of five of the new and emerging viruses that have gone global over the past decade or so, have originated in animals and jumped to humans.
Professor of Veterinary Virology at UWI, Professor Christopher Oura, made the connection between animals, humans and transmission of Dengue, Ebola, Chikungunya and Influenza, on today’s Morning Brew show on CNC3.
According to Professor Oura, when viruses are in a place where there is close contact between humans and animals, it is easy for them to make that jump.
He says that’s exactly what’s happened in the past in Africa, with Ebola, and most recently in China, in the wildlife markets in Wuhan, with the novel coronavirus, nCoV-2019.
Professor Oura explains that the particular group of coronaviruses to which nCoV-2019 belongs has the capability of jumping from animals to humans very easily, mainly because of their ability to mutate, as well as which animals are their reservoirs.
He notes that the viruses for SARS, MERS and possibly nCoV-2019 originated in bats, and may have jumped multiple species before latching onto humans.
“Some viruses have really intricate mechanisms where they can change,” the vet virologist explains. “These viruses—like the coronaviruses and influenza viruses are made up of RNA—are pretty smart at changing. They’re mutating all the time and gaining the ability to do different things. Suddenly you get one virus that doesn’t cause any clinical signs and then it becomes nasty and causes clinical signs,” he points out. “Or there’s one virus that can’t spread very easily from human to human and it mutates and gains that ability. So, the more a virus mutates, the more dangerous it can be, and the more chance it has to jump species like we’re seeing.”
The vet virologist notes that humans have different responses to the same virus because of differences in their genetic makeup and immune systems—with some persons being hospitalised with severe symptoms, and dying, while others are hospitalised and recover, and yet others show regular symptoms—just as we’ve seen with the cold and flu.
According to Professor Oura, the real challenge lies in those who display mild or no symptoms at all.
“If there’s lots of people sitting at home with no symptoms, and lots of people sitting at home with mild symptoms, it’s going to spread, because those people are still going to potentially spread the virus.”
Professor Oura says there normally is a lag period between the discovery of a virus and its vaccine.
He notes that in the case of the novel coronavirus, the lag period might be a bit longer than normal because it took the authorities a while to realise the threat extent.
However, he is confident that control and containment measures being employed now—in China, here in Trinidad and Tobago and around the world—will ensure the virus does not take too many human lives, and can be stamped out.
Story by JESSIE-MAY VENTOUR