Hog farmers are warned to be vigilant about biosecurity practices to ward off emerging diseases that may threaten the health of their swine herds, a trio of veterinarians said last week at the Iowa Pork Congress.

Farmers continue to battle occasional outbreaks of PEDV and PRRS, but other diseases are also a concern, the vets said.

One of those diseases, Seneca Valley virus, usually isn’t seen very often in Iowa, but emerged as a larger threat last year with 33 cases confirmed in the state, said state veterinarian Dr. David Schmitt.

"It’s usually something we end up seeing every two to three years," he said. "This year (2015) was different."

Pigs affected by...