the most common infectious swine disease, characterized by septicemia and cutaneous exanthema. The causative agent is the bacterium Erysipelothrix insidiosa, which was first discovered in 1882 by L. Pasteur and L. Thuillier. This bacterium is widely distributed in nature and is resistant to many unfavorable factors; it is preserved in soil as long as seven to nine months and in the water supply as long as three and one-half months.

Young animals from three to 12 months old are especially susceptible to swine erysipelas. Cases of erysipelas have been observed in turkeys and occasionally in horses, cattle, sheep, dogs, and other animals. Humans may also become infected. The principal source of the causative agent is infected swine. The causative agent may be transmitted by the nondisinfected products of the slaughter of sick animals, or through drinking water, the soil, or the objects used in caring for the animals. Infection occurs through the gastrointestinal tract, skin, or respiratory organs. The carriers of the causative agent may be rodents, insects, or healthy pigs, which may become infected under conditions of stress.

The spread of swine erysipelas is promoted by high temperatures and humidity and by the crowded conditions the animals are kept in. Swine erysipelas may cause the animal to perish within several hours; the disease also has acute, subacute, and chronic forms. Symptoms include a high temperature, disorders of the gastrointestinal tract, disruptions in heart function, weakness, and the formation on the skin of pale pink swellings (inflammatory erythemas) that gradually turn dark red. With chronic swine erysipelas symptoms include those of endocarditis, necrosis of the skin, and polyarthritis. A diagnosis is based on epizootiological and clinical data, as well as on the results of laboratory tests. Surviving swine acquire a stable immunity.

Antierysipelas serum and antibiotics are used to treat swine erysipelas. Preventive measures include vaccinations, the periodic disinfection of the premises and yards, and the control of rodents and insects. When swine must be slaughtered, the farm is quarantined, and the transport of swine to and from the farm is prohibited, as is the transport of nondisinfected meat. The meat is used as food only after cooking.