A deadly virus that kills entire piglet litters at a time continues to spread to farms across the United States – and scientists don’t yet have a cure for the disease.

First reported in the U.S. in May, porcine epidemic diarrhea virus, or PED, continues spreading to new farms across the country, says Dr. Lisa Becton, the director of research at the National Pork Board. The disease, which is not harmful to humans or fatal to older pigs, has afflicted piglets in countries like South Korea, China and Thailand – but until May was never before seen in the United States.

“There’s no definitive answer as to what causes it,” says Dr. Becton. She says initial epidemiological studies are just beginning to be published.

As infected farms lose thousands of piglets each week to the disease, many U.S. hog farmers are taking costly preventative measures to protect their livestock from PED. And with a death toll that may be in the hundreds of thousands, according to the American Association of Swine Veterinarian’s Harry Snelson, some economists say the cost of pork products may soon be on the rise.

How the Disease Is Spread

Dr. Becton says PED is spread by fecal-oral contact with manure, so hog farmers eager to prevent the disease are focusing on cleanliness and sanitation.

“People aren’t carrying anything with them into the farms, and are wearing clean boots and clean coveralls. They’re trying to focus on clean supplies coming in,” says Dr. Becton. She says the spread from farm to farm depends on the level of interaction.

Once infected, Dr. Becton says the virus takes between 28 and 48 hours to incubate; piglets fall ill within five days.

“It’s essentially a diarrhea disease, with some vomiting,” says Dr. Becton. “The death loss comes from the rapid dehydration.” PED is not breed-specific, and while it can affect older pigs, it’s generally fatal only in piglets.

“If you’re a pig, you will be sick,” says Dr. Becton. “But if there’s any good news, it’s that it doesn’t affect humans by any means.”

Because farmers aren’t required to report PED, Snelson suggests that the total number of cases in the country has been under-reported. As of the end of July, the USDA had received notice of 403 PED-positive tests, according to the AASV. Snelson says the death toll may be in the hundreds of thousands.

Dr. Becton says the National Pork Board is investing $800,000 to study the virus and devise strategies for containment and elimination. The disease is mostly contained to Midwestern states like Oklahoma, Iowa, Colorado and Minnesota, though Snelson says there have been cases along the East Coast.

The Cost of the Disease

Mark Greenwood, senior vice president of AgStar Financial Services, which provides financing to pig farmers, says PED can cause pig farmers to take a 7-8% hit across the board, as an average-sized farm could lose over one thousand piglets each week.

If the disease continues to spread, Greenwood says PED could cost farmers $12 to $16 dollars more per pig. Even though grain prices are falling due to a bountiful harvest, Greenwood predicts consumers could see a price increase on pork prices if the disease doesn’t run its course quickly.

“Lower supply would increase overall costs, so for sure you could see a rise in pork costs. There’s always that potential,” he says.

While Greenwood says PED may decimate some farmers’ profit margins, he says his clients have not yet come to him looking for help with operating costs or cash-flow needs resulting from the virus.

Jude Becker of Becker Lane Organic Farm in Dyersville, Iowa says farmers in his surrounding area have been affected by PED.

“The rate of loss is almost 100% once the farm has been affected – it’s really devastating,” says Becker.

He says he’s put into place an intense biosecurity plan to prevent the spread of PED to his farm.

“We’ve upped our watchfulness about visitors. Our veterinarian and his helpers bring separate clothes if they come to the farm, and they wash their boots off with disinfectant,” he says.

He says his truck driver, who moves the pigs to the slaughterhouse, has taken to cleaning down the interior of his truck with a hot-steam pressure washer between each trip.

“It’s an extra $100 every time the truck comes,” says Becker. “I haven’t calculated the cost per animal, but it’s certainly nothing to laugh about.”

Jayme Sieren, one of the owners of Sieren Swine Farm in Keota, Iowa, believes his farm’s preventative measures haven’t taken a huge toll on operating costs – but whatever the price tag, it’s worth every penny.

“At any given time, we probably have between 300 and 400 piglets. It would be a pretty sizeable cost – between $15,000 and $20,000 in pig costs alone,” says Sieren.

Nick Jones, the general manager of Eden Farms, a network of 35 small pig farmers in Des Moines, Iowa, says he’s less concerned about his business getting hurt by PED, because his risk is minimized by the number of producers.

“If we had one or two giant farms, that would be concerning, but our largest farm only makes up 20% of our inventory,” says Jones. So far, none of the farmers contributing to Eden Farms have been infected, to Jones’ knowledge.

While the farmers seem confident that preventative measures are helping, they worry over the fact that there is no cure in sight.

Snelson says the variant of the disease seen in China was first diagnosed in 2012 – and is still circulating through the country.

“Of course our industry is quite a bit different from China’s … but we still don’t know what it’s going to do when the cold weather gets here,” Snelson says.

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