History of leptospirosis and leptospira.

Leptospira was isolated and identified as the causative agent of the severe human syndrome Weil's disease about 100 years ago almost simultaneously, but independently, by workers in Japan and Europe. Since that time leptospires have been isolated from almost all mammalian species on every continent except Antarctica, with leptospirosis now recognized as the most widespread zoonosis worldwide and also a major cause of disease in many domestic animal species. Recent advances in molecular taxonomy have facilitated the development of a rational classification system, while the availability of genome sequences and the development of mutagenesis systems have begun to shed light on mechanisms of pathogenesis that appear to be unique to Leptospira.