ABSTRACT
Leptospira organisms are slender, round, active, and mobile spirochetes with one or both ends bent in the form of a hook.They are generally between 5 and 15m long and, unlike Treponema pallidum, they are readily cultured on relatively simple bacteriologic media. Virtually all of the pathogenic leptospires are represented in the L. interrogans group. Although there are over 100 serotypes of L. interrogans, the great majority of infections in humans are from the following serotypes: L. icterohaemorrhagiae, L. canicola, L. grippotyphosa, L. pomona, L. hebdomidis, L. mitis, L. bovis, L. autumnalis, and L. kasman.
