Learn More About a Disease


Swine erysipelas is a contagious infectious disease caused by Erysipelothrix rhusiopathiae, a tiny rod-shaped bacteria. Though this is not a new disease in pigs, erysipelas has increasingly become a concern for pork producers. In Canada, the disease was first diagnosed in Saskatchewan in 1933.

Clinical Signs +

Swine erysipelas has three main forms, but the most common are acute and chronic. The acute phase is characterized by unpredictable and sudden death in herds, and episodes of fever, sore joints and red diamond-shaped cutaneous lesions appearing all over the animal's body.  These cutaneous lesions are easily recognizable and may take a purplish tinge on the head and ears. Pigs suffering from erysipelas have a high fever and stop eating; they cry out if touched. An acute infection can be fatal; in chronic cases, the animal survives, but suffers from swollen joints and lameness.1 In Canada, swine erysipelas is most common in its arthritic form. It leads to significant financial losses due to the deformities it causes and the high percentage of condemned slaughtered carcasses.3   

Transmission +

The erysipelas bacterium is extremely resistant; it can survive and multiply in humus-rich soil in ideal humidity and temperature conditions. It resists putrefaction and decomposition.  Soil contamination therefore plays an important role in the spread of the disease. The feces and urine of sick animals contaminate the soil, feed and drinking water. Pigs carrying the bacteria in their tonsils and intestinal lymph glands and that are asymptomatic are other sources of contaminated soil and feed. The disease spreads to healthy swine, mainly through ingestion of contaminated food and water. However, bacteria may enter through small wounds or abrasions in contact with contaminated soil. Blood-sucking insects can also transmit the infection.1, 2

Diagnosis +

Diagnosis of erysipelas is based on clinical signs, cutaneous lesions, laboratory-confirmed isolation of the pathogenic agent, and response to antibiotics. The acute form of the disease is difficult to diagnose because pigs show only fever, lack of appetite and lethargy. When the disease affects several pigs, the presence of cutaneous lesions supports the clinical diagnosis. However, these lesions can be caused by other infectious agents.  In the chronic form of the disease, arthritis and valvular endocarditis (during necropsy) can establish a presumptive diagnosis of the disease.1

Treatment +

The bacterium is very sensitive to penicillin.  Infected pigs must be treated without delay. In general, there is a significant improvement in clinical symptoms in 24-36 hours. During an infectious episode, health rounds should be performed twice a day. For nurseries and grow-finishing cases, treatment in water with penicillin is warranted if a large number of animals are affected. However, new cases often appear a few days after the end of treatment. As such, strategic vaccination in drinkng water should be considered.4

Consult your veterinarian before administering antibiotics and vaccines to animals. Your veterinarian is the best source of recommendations that are truly adapted to your farm.

Prevention +

Because of the spread of the infection on farms, prevention is currently through vaccination against Erysipelothrix rhusiopathiae.The vaccine does not prevent disease in pigs that are already infected. In addition to vaccination, hygiene and sanitary measures can prevent the disease.


1 Maladie des porcs au Canada, Agriculture and Agri-Food Canada, Ottawa, Ontario

2 The Merck Veterinary Manual, Third Edition, Rouget, pp. 504-506

3 Diseases of Swine, 8th Edition, Chapter 31, pp. 419-430

4 Agri-Nouvelles, Le Rouget, Dec. 2008, pp.14-15