Classical swine fever (CSF) is most often transmitted through the ingestion of contaminated feed or garbage. However, the virus may also be spread through open wounds and mucous membranes, contact with bodily secretions or feces of an infected pig, physical transfer from a contaminated object, human or insect, sow to piglet transfer or inhalation in close quarters.

There are three forms of CSF: acute, chronic and mild. The clinical signs of the acute form of CSF may include:

  • Persistent high fever
  • Weakness
  • Lethargy
  • Ataxia (incoordination)
  • Huddling
  • Anorexia (unwillingness to eat)
  • Conjunctivitis (Pink-eye)
  • Constipation and/or diarrhea
  • Reddish/purplish discoloration of the skin of the abdomen, inner thighs and ears

The acute form of CSF progresses rapidly once clinical signs have begun and death usually occurs within 1-2 weeks with mortality approaching 100%. Click here to view photos of swine with CSF.

The clinical signs of the chronic form of CSF are the same as the acute form but are intermittent instead of persistent. However, chronic CSF infection may weaken the pig’s immune system making it susceptible to a variety of other infections. Swine infected with the chronic form of the disease may live for months but almost always succumb to the disease.

Swine with the mild form of CSF may not have any clinical signs of disease. These swine will persistently shed the virus in their feces exposing the rest of the herd. Often, the only sign of a mild CSF infection in the herd is poor reproductive performance including stillbirths or mummies, piglets born with persistent tremors or malformed organs and piglets born without signs of the disease that become ill months later.

There is currently no treatment for classical swine fever. Any pig suspected of having CSF should be immediately quarantined and examined by the State Veterinarian.