Systematic Veterinary Bacteriology and Mycology

HISTORY AND HABITAT

History

• Weil described the first case of leptospirosis in man in 1886.
• The causative agent of Weil’s disease was isolated by India in 1915 and named L. icterohaemorrhagiae.
• Subsequently a very large number of leptospires have been isolated from human patients and animals from different parts of the world.

Synonyms of leptospirosis

• Weil’s disease, Seven-day fever, Japanese autumnal fever, Rice field fever, Sugar cane fever and Stuttgart disease (dogs).

Natural habitat

• Leptospirosis occurs worldwide. Leptospires are present in the proximal convoluted tubules of mammalian kidneys (Sometimes genital tract) and are excreted in urine, often for several months. Characteristically, a reservoir host shows minimal or no clinical signs.
• Several animals act as carrier. Rats are particularly important and they carry most pathogenic serotypes.
• Animal carriers often excrete upto 100 million leptospirae per ml of urine.
• A warm moist environment with the presence of ground water with a neutral or slightly basic pH favours the survival of the Leptospira outside the host.
• In India the disease has been more frequently reported from southern states than rest of the country.