Isolation and characterization of Leptospira spp. from raccoons in Japan.

We investigated whether raccoons (Procyon lotor) carried leptospires in their kidneys in Japan. Leptospira was isolated from 2 of 71 raccoons captured in Kanagawa Prefecture and 1 of 53 raccoons at a zoological park in Nagasaki Prefecture. Anti-Leptospira antibodies were detected in 16 of 124 raccoons (12.9%) in Kanagawa and 33 of 53 raccoons (62.3%) in Nagasaki, respectively. The partial nucleotide sequences of their flaB genes suggested that the isolates belonged to L. interrogans. The serovars of the isolates were identified as Copenhageni/Icterohaemorrhagiae (1 strain in Kanagawa) and Hebdomadis (1 strain both in Kanagawa and Nagasaki) by reactivity with the reference antisera and restriction fragment length polymorphism (RFLP) analysis based on pulsed-field gel electrophoresis and cross-agglutination-absorption test, respectively. RFLP analysis on the serovars Hebdomadis strains revealed genetic diversity among serovar Hebdomadis. Although it is unclear if the raccoons carried leptospires in their kidneys at the time imported, there is no doubt that imported animals are a new reservoir animal of leptospires in Japan.