At the World Pork Expo in Des Moines, Iowa, the pigs seemed fine. It was the humans who were uneasy. A deadly virus called Porcine Epidemic Diarrhea virus (PED) has killed an estimated 8 million young pigs.
Sows that have survived are not showing as much immunity as farmers had hoped for—immunity they could pass on to the next generation. And while millions of dollars are being spent to try to contain new outbreaks, no vaccine has been developed.
A small agricultural biotech company called Harrisvaccines in Ames, Iowa, may have a treatment. Its new vaccine does not yet prevent an outbreak of PED, but it may reduce the harm it causes.
"What we're seeing in the field is that farms that are struggling with 40 to 50 percent mortality are able to bring that down significantly to maybe 10 to 15 percent," said Joel Harris, head of sales and manufacturing for Harrisvaccines.
The company's new PED vaccine has USDA approval and can be used with a veterinarian's prescription. It's still waiting for full FDA approval.
This week in Des Moines, Harris explained how the treatment has transformed his small company. Last year, privately held Harrisvaccines sold about 800,000 doses of other types of vaccines. This year, with the PED treatment, it expects to sell 5 million doses.
Read MoreUS hog losses from virus at 8 million, but rate slows
"What makes us unique is we don't actually have to grow the virus to make our vaccine," Harris said. Instead, his company uses a gene sequence of the virus. It takes four to six weeks to create the vaccine, and it's all being done in Iowa. Business is booming, even as Harrisvaccines waits for FDA approval.
"We're hiring," he said.
—By CNBC's Jane Wells.