Submitted to: Compendium of Continuing Education
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 3, 1996
Publication Date: N/A
Interpretive Summary: Vaccinating cattle with Brucella abortus strain 19 and removing animals with brucellosis from vaccinated herds has been used for over 50 years as program to eradicate brucellosis from cattle in the United States. However, the program has failed to eradicate brucellosis and has cost between 4 to 5 billion dollars during the past 30 years. Tests have revealed that a new vaccine, B. abortus strain RB51, is better than the strain 19 vaccine because cattle vaccinated with strain RB51 do not produce antibodies which are detected in diagnostic tests for brucellosis. Therefore, cattle having brucellosis can be more easily identified and the eradication of brucellosis from cattle can be more rapidly achieved by using the strain RB51 vaccine. The vaccine is also safe for use in cattle and effectively prevents brucellosis and abortions that are caused by infection with B. abortus. The strain RB51 vaccine has recently been approved as an official brucellosis vaccine for cattle by the United States Department of Agriculture, Animal and Plant Health Inspection Service (APHIS). This article summaries results from a 4-year Agriculture Research Service investigation of the safety and efficacy of the strain RB51 vaccine that were important for vaccine approval by APHIS.
Technical Abstract: Control of brucellosis in cattle in the United States currently relies on vaccinating cattle with B. abortus strain 19, and detection and slaughter of cattle that are infected with field strains of B. abortus. Identifying cattle having brucellosis can be complicated since the strain 19 vaccine induces antibodies that are detected by serodiagnostic tests for brucellosis. Tests have revealed that a new vaccine, B. abortus strain RB51, is safe, efficacious, and does not induce antibody which interferes with the serological diagnosis of brucellosis. The vaccine will facilitate the identification and removal of cattle with brucellosis from vaccinated herds during completion of the brucellosis eradication program in the United States. The strain RB51 vaccine has recently been approved as an official calfhood brucellosis vaccine for cattle by the United States Department of Agriculture, Animal and Plant Health Inspection Service. The strain RB51 vaccine also has the potential for controlling brucellosis in goats and sheep, and in wildlife (bison, elk, feral swine) without compromising the ability to diagnose brucellosis in these species. This article reviews the immunology and pathology of the strain RB51 vaccine, and its efficacy in preventing brucellosis in cattle and other animals.