Brucella suis biovar 2 isolations from cattle in Poland

Area of Science:

• Veterinary Microbiology
• Infectious Diseases
• Epidemiology

Background:

• Bovine brucellosis is a significant zoonotic disease caused by Brucella species.
• While largely eradicated in the EU, ongoing surveillance is crucial for early detection.
• Poland, aiming for official disease-free status, monitors cattle for brucellosis re-emergence.

Purpose of the Study:

• To investigate bacteriological findings in Polish cattle with positive serological brucellosis tests between 2002-2011.
• To identify Brucella species and biovars in slaughtered cattle exhibiting serological evidence of infection.
• To assess the epidemiological role of newly identified Brucella strains in cattle.

Main Methods:

• Serological testing of 176 cows using Rose Bengal test (RBT), Serum Agglutination Test (SAT), Complement Fixation Test (CFT), 2-mercaptoethanol test (2-ME), Coombs test, and ELISA.
• Bacteriological culture of tissue samples for Brucella isolation.
• Conventional and molecular (PCR) methods for bacterial identification and biotyping.

Main Results:

• All sera tested positive by RBT and SAT; 170 were CFT-positive.
• Brucella abortus was not isolated from any samples.
• Brucella suis biovar 2 was isolated from 5 cows, marking its first report in Polish cattle. Three positive cases originated from the same herd.
• PCR confirmed the isolated bacteria as B. suis biovar 2.

Conclusions:

• Brucella suis biovar 2, prevalent in wildlife reservoirs (wild boars, hares) in Poland, can infect cattle.
• This finding indicates a significant role for B. suis biovar 2 in bovine brucellosis epidemiology and control challenges in Poland.
• The study underscores the importance of including B. suis biovar 2 in surveillance and control strategies for bovine brucellosis.