How Did a Piglet-Killing Virus From China Enter the United States?
A lethal virus that is almost 100 percent fatal to baby piglets on U.S. farms has been traced to China. Researchers haven’t yet been able to figure out how the piglets became infected with a virus that originated in far off Anhui province in eastern China. “The exact source of the origin is difficult to identify at this point,” researchers write in a report published last week in the American Academy of Microbiology journal mBio.
The symptoms of Porcine epidemic diarrhea virus (PEDv) include acute vomiting, severe intestinal distress and watery diarrhea. In baby piglets less than ten days old, the mortality rate is 80 to 100 percent. Older pigs who contract PEDv are sick for days but seem able to recover.
PEDv is not dangerous for humans and does not threaten food safety, according to veterinary researchers and U.S. Department of Agriculture officials.
Researchers are working on a vaccine for PEDv, which has been spreading across the United States since May.
As of October 6, a total of 768 cases of PEDv have been confirmed in 18 states including Colorado, Indiana, Iowa, Minnesota and Ohio, the site of the earliest confirmed case back in April.
Three strains of PEDv found in the United States are 99.5 percent similar in their genetic makeup to a strain identified in China, according to veterinary researchers at the Virginia-Maryland Regional College of Veterinary Medicine at Virginia Tech. It’s not yet known if the virus can jump from species to species but it might be able to. The U.S. PEDv strains have similarities to a bat coronavirus, the very sort of virus that has been associated with Middle East Respiratory Syndrome (MERS), a severe respiratory illness that first appeared in Saudi Arabia in 2012 and has been linked to bats. Pigs can catch what is called Nipah virus from bats.
PEDv Could Kill Thousands of Baby Piglets in a Matter of Weeks
The authors of the report about PEDv in the United States emphasize the need for veterinarians to recognize the symptoms of the disease and also for farm workers to “practice strict biosecurity and good sanitation procedures.” A University of Minnesota report notes that the virus is “believed to spread from farm to farm through the transport system,” via manure on a truck or on the driver’s clothes. Farmers have been taking precautions by washing, disinfecting and sanitizing trailers; having anyone working with pigs shower twice before entering facilities and disposable plastic boots.
The virus is expected to spread more quickly now that it’s fall, when piglets are born. One sow farmer can produce 1,000 – 2,000 piglets a week but PEDv could wipe out “nearly all newborn pigs for weeks,” according to Iowa news station KCRG.
The link between PEDv in the United States and strains of the virus in China shows how easily diseases can spread all across the globe and all the more so at a time when the United States, like many other countries, imports more food (and now that a Chinese company, Shuanghai has Smithfield Foods, the largest pork producer in the U.S.). As Tom Burkgren, executive director of the American Association of Swine Veterinarians, said to the New York Times when PEDv was first detected last spring, “The world got a lot smaller that day. If PEDv. can get into the United States, what about some of the even more nasty viruses?”
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