Even under the best circumstances, vaccines do not provide absolute protection against disease. Producers can, however, maximize the benefit of vaccines they administer to cattle by working to eliminate the most common causes of vaccine failures.
Texas A&M veterinarian Robert Sprowls lists the following factors that can contribute to vaccine failure:
- improper storage
- improper handling and administration
- improper reconstitution
- failure to mix well
- contamination of syringe (bacterial or disinfectants)
- indiscriminate mixing of vaccines and antibiotics
- using a product beyond expiration date
- wrong injection site
- improper dosage
- failure of the animal to mount an immune response
- heavy parasitism;
- existing infections
- immunological incompetence-genetic inability to mount a normal immune response.