Brucellosis 2003 proceedings - PHIDIAS

Poster Session
14- HIGH PREVALENCE OF SEROVAR 3 OF Brucella abortus IN THE REGION
OF CANTABRIA (SPAIN).
J. Agüero 1 , A. Ocampo 1 , C. Marín 2 , G. Gradillas 3 and J.M. García-Lobo 1 . (1) Departamento de
Biología Molecular. Universidad de Cantabria, Spain. (2) Servicio de Sanidad Animal. Diputación
General de Aragón, Spain. (3) Servicio de Laboratorio y Control. Dirección General de Ganadería.
Gobierno de Cantabria. Spain.
Animal brucellosis is still highly prevalent in the region of Cantabria, which is
located in the North of Spain. The main incidence is in cattle, where the current
estimation of the presence of the disease is that of 0.85%.
We present herein our data resulting from the characterization of a wide
number of field isolates of Brucella spp, mainly from cattle, collected over the last
three years. The identification of species and biovars were determined both by
phenotypic and genotypic methods. For the phenotypic characterization we
performed the classical techniques addressed to this aim: dyes sensibility, CO 2
requeriment, SH 2 production, phage typing and agglutination with monoespecific
sera. The genotypic studies were accomplished by PCR analysis, using
oligonucleotides capable of distinguishing the species and or biovars isolated from
the different samples. The strains were further characterized by RFLP analysis using
the insertion sequence IS711 as genetic marker.
The majority of the strains analyzed proved to be belonging to the biovar 3 of
B. abortus, and exhibited special genetic features which were not observed in the
reference strain for this biovar. On the basis of these results, the possibility of the
existence of an endemic clone of B. abortus in this region is discussed.
15- ANTIMICROBIAL SUSCEPTIBILITY OF Brucella canis ISOLATED IN KOREA.
Jongwan Kim 1 , Jongsam An 1 , Jaehak Kim 1 , Youngju Lee 1 , Jongman Kim 1 , Yiseok Joo 1 , Ryunbin Tak 2 .
(1) National Veterinary Research and Quarantine Service, (2) College of Veterinary Medicine,
Kyungpook National University, Republic of Korea.
Antimicrobial treatment of canine brucellosis has been shown variable results,
including relapse of brucellosis. The purpose of this study was to test the in vitro
susceptibility of 15 antimicrobial agents against 3 and 52 isolates of Brucella canis
isolated from dogs in Korea in 1994 and 2002, respectively. Minimal inhibitory
concentration (MIC) and minimal bactericidal concentration (MBC) were determined
using conventional microdilution broth methods. Tetracyclines (minocycline,
doxycline) and aminoglycosides (gentamicin, streptomycin) showed greatest
suppressive activity against Brucella canis (MICs 0.06-0.5 µg/ml). Fluoroquinolones
(norfloxacin, ciprofloxacine) and rifampin showed equivalent activity (MICs 32 µg/ml).
Interestingly, recently isolated 52 strains showed 16-64 times higher macrolides
(erythromycin, spiramycin, tylosin) MICs than 3 strains isolated in 1994. MBC
analysis revealed aminoglycosides and fluoroquinolones showed greatest
bactericidal activity (MBCs 0.12-1.0 µg/ml), while beta-lactam antibiotics
(ampicillin,cephalothin), lincosamides, and sulfisoxazole showed least bactericidal
activity (MBCs 16->32 µg/ml). Interestingly, tetracyclines showed highest MBC/MIC
ratio (128X). In addition, macrolides showed broad range of MIC and MBC.
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Brucellosis 2003 International Research Conference