Last spring, a killer virus suddenly appeared on a hog farm in Ohio.
Now, almost a year since it was first detected, the virus has spread to 30 states, wiping out 10 percent of the U.S. pig population. The virus, known as porcine epidemic diarrhea virus, or PEDv, targets the lining of a pig's small intestine, causing extreme diarrhea. It's highly contagious, and spreads by contact with infected manure or feed.
As many as 7 million pigs of the country's 63 million herd have died from PEDv since the fast-spreading outbreak began, according to Reuters, sinking both revenue and morale across U.S. hog farms. Here's what you need to know about the deadly disease.
No one knows where it came from. The disease is not a new one, and outbreaks have been reported in Europe, China, Korea, and Japan. But officials have not found any clear evidence of how the virus entered the U.S. Some suspect the outbreak originated in China, where a virus nearly identical to PEDv infected pigs in Anhui Province. China has imposed an import ban on U.S. live pork in response to the outbreak here.
The unusually cold and snowy winter didn't help. PEDv thrives in cold, damp environments. The number of reported cases of the infection tripled between last December and this month.
The virus is incredibly lethal. PEDv is almost 100 percent fatal in pigs less than three weeks old.
But not for humans. The virus only affects pigs, and poses no health risk to humans or other animals.
And there's no vaccine. But farmers, veterinarians, and pork organizations are trying to find one. The National Pork Board has already spent $1.1 million on research to understand how the virus works and how to stop it.
In the meantime, farmers are stepping up biosecurity. This means imposing stricter standards for cleanliness on hog farms. Some farmers require workers to change their clothes when entering and leaving barns, while others have banned outsiders from their property altogether. Farm employees are stocking up on disinfectant, careful not to spread the virus during their daily activities.
The outbreak has sent retail pork prices to record highs. This time last year, pork cost $3.52 a pound. Now, the meat is selling for $3.83 a pound, an all-time high for the U.S. For meat-eating Americans, summer barbecues may be pricier than usual. But don't worry about chowing down — U.S. pork is still safe to eat.
And it's spreading. The virus has cropped up in Canada, whose pork industry is closely connected to our own.