A new swine virus, distinct from the deadly PEDv pig virus, has been found in fecal samples taken from four different farms in Ohio last month and early this month, the Ohio Department of Agriculture said on Wednesday.
This is only the second time the virus has been reported and the first time it has been seen in the United States, said Yan Zhang, a scientist in the department's Animal Disease Diagnostic Laboratory.
The pigs that contracted the new virus, called Swine DeltaCoronavirus (SDCV), suffered from diarrhea, which is also a symptom of Porcine Epidemic Diarrhea virus (PEDv) and transmissible gastroenteritis (TGE). But state officials said the new virus is different.
Like PEDv, the virus affects piglets and older pigs, and the clinical signs are very similar to PEDv; but the mortality rate appears to be lower, Zhang said.
However, vaccines used against PEDv and TGE will not likely cross-protect hog herds against the new virus, Zhang said. But he said this is not yet known for sure.
Of the four Ohio farms where the virus was discovered, one tested positive for Swine DeltaCoronavirus but negative for PEDv and TGE. The other three farms tested positive for both PEDv and Swine DeltaCoronavirus.
"This virus is closely related to a coronavirus detected in Hong Kong in 2012," the Ohio Department of Agriculture said.
The discovery of the new virus strain comes as the U.S. pork industry is battling the spread of PEDv, which has killed an estimated 4 million pigs across 23 states since it was first discovered in the United States last April.
"The value of this finding is that it provides a new diagnostic tool for producers that have piglets with signs of PEDv but test PEDv-negative. There is now another test that can be run to determine if that virus is present," said Beverly Byrum, director of laboratories for the department.
Like PEDv, the Swine DeltaCoronavirus is labeled a transboundary disease by the U.S. Department of Agriculture, so it is not required to be reported, said Tom Burkgren, executive director at the American Association of Swine Veterinarians.
"The discovery creates a whole new line of research to be done. It also raises questions about how did it get into the United States, as it has not been seen here before," Burkgren said.
A second strain of PEDv was identified last week by researchers at Iowa State University.
The virus cannot spread to humans or other species and poses no risk to food safety, the Ohio Department of Agriculture said. The agency said further research needs to be conducted to determine whether or not the virus is the cause of diarrheal disease in affected pigs.