Experimental hamster infection with a strain of Leptospira borgpetersenii Ballum isolated from a reservoir mouse in New Caledonia
Résumé
Leptospirosis is a neglected zoonosis caused by pathogenic Leptospira. In this study, we characterized the virulence of isolate B3-13S obtained from a wild mouse (Mus musculus) captured in New Caledonia, subsequently identified as a bacterium belonging to the L. borgpetersenii serogroup Ballum. Hamsters were infected with an intraperitoneal injection of 2 x 108 bacteria, resulting in severe histopathological organ damages consistent with tissue lesions previously observed in other strains. Hamsters were also injected with 1 x 108 or 5 x 107 bacteria and animals that recovered showed renal carriage of leptospires in concentrations similar to the bacterial load quantified in mouse kidneys, with urinary shedding of bacteria up to four weeks postinfection. The serogroup Ballum is increasingly reported in human leptospirosis and these results highlight the use of the B3-13S isolate for the development of models resulting in either severe acute or chronic forms of the infection, allowing for better characterization of its pathogenesis.