Pseudorabies is a disease caused by the virus Porcine herpesvirus 1. The virus spreads through saliva and nasal secretions and can live for hours on a pool of water, dewy grass, or soil. Soil contaminated with feces from an infected animal can be a source for spreading the virus as well. Domestic swine are now vaccinated for pseudorabies and the pigs in farms across the U.S. and western Europe are free of the disease. Feral swine populations still carry the virus, and farmers must be careful to ensure that feral swine never come in contact with livestock or resources used to care for livestock.
The symptoms for pseudorabies in adult swine are not obvious. Adults appear to be asymptomatic, but they suffer high abortion rates and mortality in infected piglets is almost certain. The virus is transmittable to other animals, but not to humans. In cattle, dogs, and cats it is usually fatal.