It’s unlikely that COVID-19 could move from humans to livestock.
Regardless, infectious disease specialists at the University of Saskatchewan want to know for certain if humans can transmit the novel coronavirus to farm animals.
“We’re looking at pigs and poultry, and potentially also cattle,” said Volker Gerdts, director and chief executive officer of the Vaccine and Infectious Disease Organization at the U of S.
VIDO-Intervac has been in the news because its scientists are seeking a vaccine for COVID-19. They have successfully grown the virus in a cell culture and are now testing a new vaccine in animals.
That work is the number one priority at VIDO-Intervac, but research on human-to-livestock transmission is also moving forward.
To determine if pigs, poultry and cattle are susceptible, VIDO-Intervac is partnering with Canadian Food Inspection Agency scientists in Winnipeg. The first step is to take cells from livestock and lab tests to determine if COVID-19 can infect the cells.
“The next step would be to actually expose the animals to the virus and see if you can get a productive infection,” Gerdts said.
A couple of years ago, scientists did something similar with the Zika virus. In turned out that livestock could be infected but they didn’t shed a lot of the virus, Gerdts said.
If people can infect pigs or other livestock with COVID-19, the animals could become a source of future infection for the human population.
“Sometimes they get infected and don’t get sick. That’s good for the animal, but we still need to know if they can spread it or not,” said Scott Weese, a University of Guelph veterinary professor and an infectious disease expert.
Of the species of livestock, pigs could be most susceptible to COVID-19, he added.
“There are a few other animal species — cats, ferrets and pigs — that this virus might be able to affect,” he said.
Certain viruses, such as rabies, can infect nearly all mammals, while other viruses infect a narrow group of animals, he added.
“They (might) have a product on their cells that the virus likes to attach to…. Some of them (animals) just have receptors that are more similar,” he said.
“Influenza is a great example. (Pigs) can be susceptible to our (human) flus.”
It will take weeks or probably months to answer the questions surrounding livestock and COVID-19.
In the meantime, the U of G isn’t taking any chances. Earlier in March it beefed up biosecurity at its livestock facilities. Visitors are no longer permitted at the livestock centres and sick employees shouldn’t get close to the animals.
“We want to treat animals just like people, essentially,” Weese said.
“If you’ve got a farm worker that’s (ill) … you can’t (tell them) to stay away from people and go work in the barn.”
Commercial hog barns in Canada rarely allow visitors, but when possible, barn workers should keep a safe distance from livestock, Weese added.