Primer aislamiento de Leptospira borgpetersenii serovar Hardjo tipo Hardjo Bovis a partir de un caso clínico en Argentina / First isolation of Leptospira borgpetersenii serovar Hardjo type Hardjo Bovis from aclinical case in cattle in Argentina

Resumen Se describe el primer aislamiento y la tipificación molecular de Leptospira borgpetersenii serovar Hardjo Bovis en Argentina, obtenido a partir de orina de vacas abortadas de unrodeo de cría ubicado en Saladillo, provincia de Buenos Aires. Los abortos coincidieron con unperíodo de importantes inundaciones, en el que varios animales presentaron títulos serológicossospechosos y posterior seroconversión. El porcentaje de abortos alcanzó el 3,5% del total delrodeo, compuesto por 1700 vacas, y se aisló el microorganismo en 7 de 20 muestras de orinaobtenidas.

Abstract We here describe the first isolation and molecular typing of Leptospira borgpe-tersenii serovar Hardjo Bovis in Argentina, obtained from urine of aborted cows from abreeding herd located in Saladillo, Buenos Aires Province. The abortions occurred in coincidence with important floods with many cows presenting suspicious serological titers and subsequentseroconversion. The percentage of abortions was 3.5% of a herd of 1700 cows and the microor-ganism was isolated from 7 of the 20 urine samples obtained.

A combined approach of VNTR and MLST analysis: improving molecular typing of Argentinean isolates of Leptospira interrogans

Leptospirosis is an emerging infectious disease that has been identified as both a human and animal health problem worldwide. Regular outbreaks associated with specific risk factors have been reported in Argentina. However, there are no available data concerning the genetic population level for this pathogen. Therefore, the aim of this work was to describe the genetic diversity of Leptospira interrogans through the application of two molecular typing strategies: variable number of tandem repeats (VNTR) and multilocus sequence typing (MLST). For this purpose, seven reference strains and 18 non-epidemiologically related isolates from diverse hosts and Argentinean regions were analysed. Among them, nine genotypes and seven sequence types (STs), including three unreported STs, were described using VNTR and MLST, respectively. eBURST analysis demonstrated that ST37 was the most frequent and founder genotype of a clonal complex (CCs) containing STN1 and STN3, suggesting the importance of studying the serovars belonging to this CC in Argentina. The data from maximum parsimony analysis, which combined both techniques, achieved intra-serovar discrimination, surmounted microscopic agglutination test discrepancies and increased the discriminatory power of each technique applied separately. This study is the first to combine both strategies for L. interrogans typing to generate a more comprehensive molecular genotyping of isolates from Argentina in a global context.