Leptospirosis is a ubiquitous
zoonosis caused by the spirochete Leptospira interrogans which has 23
serogroups and more than 200 serovars. It is globally being recorded as an epidemic threat in developing countries like India in and around the rainy season.
The annual incidence of this disease is estimated at 10 to100 per
100,000 in tropical regions and 0.1–1.0 per 100,000 in temperate areas. The spectrum of disease ranges from sub clinical infection to a severe syndrome of multi organ dysfunction characterized by headache, fever, myalgia, jaundice,
hepatomegaly and convulsions. In humans, a disease resembling Leptospirosis was
recognized as an occupational hazard of rice harvesting in ancient China.