In May, the first case of porcine epidemic diarrhea, or PED virus, was found in the United States. As of December 19, it has spread to 21 states, with 1,645 total diagnostic case submissions testing positive for PEDv, according to PEDv testing data from National Animal Health Laboratory Network, or NAHLN laboratories. This doesn't account for cases that haven't been reported.
After Iowa, North Carolina, and Oklahoma, Kansas has had the fourth largest amount of diagnosed cases – 131 as of December 19. "The number of cases being reported in the U.S. is at an all-time high," says Dr. Richard Hesse, director of diagnostic virology at the Kansas State Veterinary Diagnostic Laboratory. "Wherever young pigs are raised, that's where it's most noted because of the extremely high mortality."
Once a site is contaminated, nursing pigs are the most at-risk. "The virus infects mature enterocytes (the cells lining the intestinal tract), and baby pigs have more of them in the small intestine than older pigs," Hesse explains. This means they have more susceptible cells which become infected, causing the pig to develop severe diarrhea and die from dehydration. "It will still affect older animals, but it isn't as deadly as with a nursing pig," he notes. "Older pigs are better able to handle some dehydration than baby pigs."
It is important to note this is a production-related disease, and has absolutely no effect on food safety. "This virus does not infect people at all. In fact, the only species we know of that it infects are pigs," Hesse says. "The meat you get from the pigs that have had this disease is perfectly fine to eat."
Preventing the spread of PEDv
PEDv spreads through fecal-oral contamination. "The reason it spread so fast is there's so much virus in the feces of animals that are infected," Hesse explains. From an infected animal, there are about 10 million to one billion virus particles per gram of feces. "That's an incredible amount of virus."
This is the time of year to watch for PEDv, which is seasonal in late fall and winter, Hesse says. Within a contaminated facility, it spreads very readily, and will transfer on contact. The trick is to keep it off the farm. This is why it's important to keep up-to-date and follow biosecurity procedures, which are available at the American Association of Swine Veterinarians website and the National Pork Board website. These include protocol for:
* Cleaning and disinfecting trucks, trailers and wash bays.
* Establishing lines of separation at the cab of the truck, loading chute, and the farm site.
* Hauling mortalities to the Animal Disposal Unit, and ensuring the ADU is in a location away from other animals.
* Using clean, disinfected equipment around animals and disposing of contaminated equipment.
* When pumping manure, maintaining a line a separation from manure, and cleaning and disinfecting equipment.
Hesse says the Kansas State Veterinary Diagnostic Lab is prepared to take any case submissions for diagnostic testing.