Genus within the family of the Treponemataceae, the leptospira are slender spirochaetes 7 – 14 μm long by 0.1 μm broad with very numerous, close-set coils terminated by hooked ends. Both directional and rotatory motility is seen. There are many species, both parasitic and saprophytic; the latter occur in water and are collectively styled Leptospira biflexa.
A genus of spirochete bacteria, commonly bearing hooked ends. They are not visible with ordinary light microscopy and are best seen using dark-ground microscopy. The parasitic species L. icterohaemorrhagiae is the main causative agent of leptospirosis (Weil’s disease), but many closely related species cause similar symptoms.
A group, or genus, of spiral micro-organisms, normally found in rodents and other small mammals in which they cause no harm. When transmitted to humans by these animals, either directly or indirectly as through cows, they give rise to various forms of illness.