title: Highly virulent Leptospira borgpetersenii strain characterized in the hamster model.
abstract: Abstract. A recent study by our group reported the isolation and partial serological and molecular characterization of four Leptospira borgpetersenii serogroup Ballum strains. Here, we reproduced experimental leptospirosis in golden Syrian hamsters (Mesocricetus auratus) and carried out standardization of lethal dose 50% (LD50) of one of these strains (4E). Clinical disease features and histopathologic analyses of tissue lesions were also observed. As results, strain 4E induced lethality in the hamster model with inocula lower than 10 leptospires, and histopathological examination of animals showed typical lesions found in severe leptospirosis. Gross pathological findings were peculiar; animals that died early had more chance of presenting severe jaundice and less chance of presenting pulmonary hemorrhages (P < 0.01). L. borgpetersenii serogroup Ballum has had a considerable growth in human leptospirosis cases in recent years. This strain has now been thoroughly characterized and can be used in more studies, especially evaluations of vaccine candidates.
authors.affiliation: Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, Brazil.
authors.forename: Juliana Alcoforado
authors.initials: JA
authors.lastname: Diniz
authors.forename: Samuel Rodrigues
authors.initials: SR
authors.lastname: Félix
authors.forename: Josiane
authors.initials: J
authors.lastname: Bonel-Raposo
authors.forename: Amilton Clair Pinto
authors.initials: AC
authors.lastname: Seixas Neto
authors.forename: Flávia Aleixo
authors.initials: FA
authors.lastname: Vasconcellos
authors.forename: André Alex
authors.initials: AA
authors.lastname: Grassmann
authors.forename: Odir Antônio
authors.initials: OA
authors.lastname: Dellagostin
authors.forename: José Antonio Guimarães
authors.initials: JA
authors.lastname: Aleixo
authors.forename: Everton Fagonde
authors.initials: EF
authors.lastname: da Silva
mesh_terms: D000818:Animals; D006224:Cricetinae; D005260:Female; D007919:Leptospira / Q000145:classification* / Q000472:pathogenicity*; D007922:Leptospirosis / Q000382:microbiology* / Q000473:pathology; D008297:Male; D008647:Mesocricetus; D012727:Sex Characteristics