|Ewalt, Darla - USDA/APHIS/NVSL, AMES, IA|
Submitted to: Journal of Clinical Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 17, 2000
Publication Date: N/A
Interpretive Summary: Brucellosis is a disease of cattle that can cause abortions. It is a concern of the livestock industry because of loss in productivity and because it can result in quarantine action and possible depopulation of the herd. Suspected infections must be confirmed as quickly as possible. Currently, suspected milk, tissues, or isolates are sent to a diagnostic laboratory where it takes a minimum of 5 days to complete the conventional tests. The AMOS PCR assay is a DNA based test that takes only 1 day to complete. The study described in this report validates that the rapid AMOS PCR assay is as accurate and as precise as the conventional tests routinely used for identification of brucellosis. It also validates that the AMOS PCR test correctly differentiates vaccine microbes from the disease-causing germ.
Technical Abstract: The abbreviated Brucella AMOS PCR was evaluated to determine its accuracy in differentiating Brucella abortus into three categories: field strains, strain 19 vaccine strain, and strain RB51 vaccine strain/parent strain 2308. Two hundred thirty-one isolates were identified and tested by the conventional biochemical tests and Brucella AMOS PCR. This included 120 isolates identified as B. abortus S19, 9 as B. abortus strain RB51, 57 as B. abortus biovar 1, 15 as B. abortus biovar 2, 1 as B. abortus biovar 2 (M antigen dominant), 7 as B. abortus biovar 4, and 22 as B. abortus S2308 that were isolated from experimentally infected cattle. The Brucella AMOS PCR correctly identified each isolate as RB51/S2308, S19, or field strain of Brucella.