Pathogenic Leptospira and their animal reservoirs: testing host specificity through experimental infection

Colette Cordonin (1) , Magali Turpin (1) , Matthieu Bringart (2) , Jean-Loup Bascands (2) , Olivier Flores (3) , Koussay Dellagi (1) , Patrick Mavingui (1) , Marjolaine Roche (1) , Pablo Tortosa (1)

1 PIMIT - Processus Infectieux en Milieu Insulaire Tropical
2 DéTROI - Diabète athérothrombose et thérapies Réunion Océan Indien
3 UMR PVBMT - Peuplements végétaux et bioagresseurs en milieu tropical

Leptospirosis is caused by pathogenic Leptospira transmitted through contact with contaminated environments. Most mammalian species are infectable by Leptospira but only few act as efficient reservoir being capable of establishing long term kidney colonization and shedding Leptospira in urine. In Madagascar, a large diversity of pathogenic Leptospira display a tight specificity towards their endemic volant or terrestrial mammalian hosts. The basis of this specificity is unknown: it may indicate some genetically determined compatibility between host cells and bacteria or only reflect ecological constraints preventing contacts between specific hosts. In this study, Rattus norvegicus was experimentally infected with either Leptospira interrogans, Leptospira borgpetersenii or Leptospira mayottensis isolated from rats, bats or tenrecs, respectively. Leptospira borgpetersenii and L. mayottensis do not support renal colonization as featured by no shedding of live bacteria in urine and low level and sporadic detection of Leptospira DNA in kidneys. In contrast 2 out of the 7 R. norvegicus challenged with L. interrogans developed renal colonization and intense Leptospira shedding in urine throughout the 3 months of experimental infection. These data suggest that host-Leptospira specificity in this biodiversity hotspot is driven at least in part by genetic determinants likely resulting from longterm co-diversification processes.

Domaines: Bactériologie; Médecine vétérinaire et santé animale; Evolution [q-bio.PE]; Maladies infectieuses

Colette Cordonin, Magali Turpin, Matthieu Bringart, Jean-Loup Bascands, Olivier Flores, et al.. Pathogenic Leptospira and their animal reservoirs: testing host specificity through experimental infection. Scientific Reports, 2020, 10 (1), pp.7239. ⟨10.1038/s41598-020-64172-4⟩. ⟨hal-02610472⟩