The bacterins used for vaccination against blackleg and malignant edema are perishable products and deteriorate rapidly if they are not stored properly. The manufacturer's directions regarding storage and handing should be rigidly followed in order to assure that the vaccine is at it's highest potency. After the vaccination has been completed, any partially used vaccine containers should be discarded and not retained for later use. The bacteria that cause blackleg are capable of living in the soil. They have the capacity to form spores which can protect the organism from the effects of weather, and hence soil can remain infected for many years.
Carcasses of animals affected by the disease are the chief source of soil infection.
They harbor the germs in large numbers and liberate them from both artificial and natural body openings into the surrounding soil. For this reason, every dead animal should be promptly burned or buried. The surface of the ground may be treated by burning it over with a heavy layer of straw, used oil, etc. This disease, commonly called stable blackleg, is very similar to blackleg. In fact, the similarity is so close that often a diagnosis can be made only when the specific bacteria are identified in the laboratory.