A second round of the Porcine Epidemic Diarrhea virus found at an Indiana farm, according to a National Pork Board official, undercuts any presumption of lasting immunity from a one-time exposure.
 |  |  |  |  |  |  |  |  |
A second round of the Porcine Epidemic Diarrhea virus found at an Indiana farm, according to a National Pork Board official, undercuts any presumption of lasting immunity from a one-time exposure.