MercoPress. South Atlantic News Agency

Deadly swine virus spreading among hog farms in the US Mid west

PEDV is 99.4% similar in genetic structure to the PEDV that hit China's herds last year

A swine virus deadly to young pigs, one never before seen in North America, is spreading rapidly across the United States and proving harder to control than previously believed.

The virus now has spread to 13 states - with more than 100 positive cases to date - since it was first diagnosed in the United States last month, said Montserrat Torremorell, the Allen D. Leman Chair in Swine Health and Productivity at the University of Minnesota's College of Veterinary Medicine.

While the virus has not tended to kill older pigs, mortality among very young pigs infected in U.S. farms is commonly 50%, and can be as high at 100%, say veterinarians and scientists who are studying the outbreak.

The strain of the virus, known as Porcine Epidemic Diarrhea Virus, that is making its way across the US hog farms and slaughterhouses is 99.4% similar in genetic structure to the PEDV that hit China's herds last year, the researchers say. After it was first diagnosed in China in 2010, PEDV overran southern China and killed more than 1 million piglets, according to the Centres for Disease Control and Prevention's Emerging Infectious Diseases Journal.

The virus does not pose any health risk to humans or other animals. The meat from PEDV-infected pigs is safe for people to eat, according to federal officials and livestock economists.

No direct connection has been found between the U.S. outbreaks and previously identified outbreaks in Asia and Europe, say scientists and researchers.

PEDV was diagnosed earlier this month for the first time in Arkansas, Kansas and Pennsylvania. Previously, the virus had been found in barns in Colorado, Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, Oklahoma and South Dakota.

It has been found in baby pigs, adult sows and in other hogs being fattened for slaughter in the United States, say researchers and veterinarians who are investigating the outbreak. No known cases have been reported in Canada or Mexico.

When and how PEDV arrived in the United States remains a mystery. The total number of pig deaths from the outbreak is not known, and the uncertainty is fuelling fears among traders, meat processors and farmers about the potential impact on pork supplies later in the year.

The outbreak comes as U.S. hog and wholesale pork prices in the large hog-raising states of Iowa and Minnesota have surged to nearly two-year highs. Supermarkets are racing to fill meat cases for the summer grilling season even as supplies tighten, analysts said. Hogs supplies were already tight after last summer's historic drought drove up feed-grain costs, which prompted a higher-than-normal slaughter rate last summer.

The first U.S. case of PEDV was reported on May 17. But researchers at the National Veterinary Services Laboratory in Ames, Iowa, and other diagnostic labs have since discovered that PEDV arrived as early as April 16, according to