June 10, 2023

Veterinarian weighs-in on COVID-19 and farming

CHAMPAIGN, Ill. — We’ve read countless stories about the spread of COVID-19, also known as the coronavirus, but what impact could it have on the planting season and livestock production?

Veterinarian Jim Lowe, an expert in infectious diseases at the University of Illinois College of Veterinary Medicine, shared his perspective in a March 24 farmdoc-hosted webinar.

His efforts on infectious diseases include extensive zoonotic work, particularly around influenza, in partnership with St. Jude Children’s Research Hospital. Zoonotic is any disease that can be transmitted from one species another.

Here are several COVID-19 topics Lowe covered in the webinar.

Did the coronavirus move from animals to humans?

“That unfortunately occurs more frequently than we would like. We think most of the diseases that originated in humans came from another animal and in some cases disease that originated in animals.

“For example, we believe porcine reproductive respiratory migrated from mice into pigs. This cross-species transmission is somewhat frequent.

“The difference is that it doesn’t often take hold in the new species. A virus moves from a bat to a human, but the virus isn’t well adapted and it doesn’t replicate in humans and it doesn’t pass from human to human. That’s a good thing because this is what happens when we get a new disease in a population without a prior immunity.

“So, we go from being zoonotic to being pandemic or epidemic when we get the virus or the bacteria, and we’re really worried about viruses, established in the human host then can pass from human to human to human. That’s what appears to have happened here.”

Can COVID-19 be transmitted from humans to livestock?

“The good part is that there is zero evidence, and I don’t mean not a little bit, there is zero evidence that this coronavirus infects anything other than human beings.

“There’s a dog that was reported to be contaminated in Hong Kong, that it came back positive for the virus. The dog was never infected. It was apparently just a surface contamination.

“There are some rumors that a second dog has been contaminated there in a household. We do think that pets living in households with people who are contaminated and shedding a lot of virus could serve as a fomite — a physical carrier.

“It doesn’t appear to last on anything other than hard surfaces very long. So, we don’t think they’re a risk at all, and we’ve got to work through some cases of that, but the evidence that livestock would be either contaminated or physical carriers is just non-existent.

“I do worry about our truckers that are hauling livestock because they mix with a lot of people, they have to stop at truck stops and we clearly have to get critters to town.

“If we get a lot of people sick and we have to close a packing, that gets really ugly really quick. I’d be concerned about the truck drivers because they have a lot of contact, but there’s zero risk with the animals.”

With planting season around the corner, how do farmers need to approach the coronavirus issues?

“Farmers have clearly been declared as important. I think the advantage of living in rural USA is we’re in relatively low density and low density is important in this case. There’s less contact between susceptibles and infected.

“We’re going to start planting here hopefully sooner rather than later. As we get to that point, you have to do your job, but it’s wash your hands, wash your hands, wash your hands.”

What about those that want to “tough it out” if they don’t feel well and continue working on the farm?

“This is isn’t the time to be the tough guy. This is the time to get yourself isolated and don’t get your whole family infected and take care of yourself.

“Because if you look at the risk, these folks are on ventilators, they’re sedated, basically paralyzed and laying on their belly for days trying to make their lungs work because you quit breathing.

“If you have a cough and you don’t feel very good, this isn’t ‘I’m going to tough it out and be OK.’ This is not the flu.

“The challenge is that all this is scary because it’s unknown. I don’t think we should necessarily take it lightly, but we also don’t need to live in fear.

“This stuff is not the miasma from the pre-virus days. It’s on-contact. It’s not probably going to waft up in you nose if you’re not talking directly to somebody.

“It’s wash your hands. If your hands touch things like your pickup truck, wipe your pickup truck off, wipe your pickup truck handles off. We have to be cautious and we have to be consistent, but we don’t have to go crazy. It’s not the plague.

“But I think the big message is if you don’t feel very good, go to a doctor. This gets real bad real quick.”

What’s your opinion of the notion that as we get more sunlight and warmer weather that this will abate?

“My prediction is if you look at every other epidemic we’ve ever had, and history is a good lesson, it’s likely to get better this summer. We’ll get over this epidemic peak and that is not just sunlight, but we all get outside and we socially distance naturally and we’re not cooped up inside. It likely get better just because our society changes behaviorally in the summer.

“I’m not trying to be a doomsayer, but I think what we have to worry about is the reality that it’s likely to come back in the fall when we come back inside with a vengeance. We will have not all been exposed and knocked it off.

“Every other time we’ve had an epidemic, not really a pandemic, but an epidemic disease, it happens the first time and then the next fall when we go back indoors the virus isn’t eliminated and boom here’s the second wave of the outbreak. And normally they go in three waves.”

Is there a possibility of developing a vaccine for this?

“We have some really brilliant people working on things and they work incredible hard at really high risks for themselves. We’re going to have a vaccine. They will figure out how to make a vaccine.

“It won’t be great, but it will be as good as flu (vaccine) and that’s all you need to slow this down, to increase those numbers of resistance. I think realistically it’s 18 months. Everybody keeps saying a year.

“First of all, you have to know if the vaccine is safe and it takes time to figure that out because you don’t want to give a vaccine that makes people sick or kills people. Then you have to figure out if it works and it just takes time to figure that out.”

Once someone has recovered from the COVID-19 would they develop a resistance or still be susceptible?

“We don’t have a firm answer for that. The belief is, yes, they’re going to go into the resistant bucket. They will not get it again, but we don’t know for how long.

“We don’t know how long the immunity is to this particular virus. We obviously haven’t had infections long enough to understand that, so that will take some time to figure out.

“It probably will not be lifelong immunity, but again we don’t have to have perfect immunity we just have to get 40%, 50%, 60% of the population immune and that herd immunity will drop the severity of the disease and keep this to a dull roar.”

Can there be transmission through the supply chain?

“We don’t tend to think of respiratory pathogens moving through supply chains very well. We think about foodborne pathogens because you ingest that. Is it possible? Yes. Is it probable? Probably not.

“We don’t know, but if I just sit back and say as a scientist who thinks about disease transmission all the time, there’s a lot of things that are possible and certainly in the pig world we worry about possible a lot.

“But here we really have to worry about the probable and put the foot down and stomp out where the probable is. Probable is really person-to-person contact that that’s what we need to continue to work on.”