History of leptospirosis

Leptospirosis, or Weil’s disease as it commonly known, is a rare infection contracted from the urine of animals, usually rats. Pathogenic leptospires belong to the genus Leptospira (long corkscrew-shaped bacteria, too thin to be visible under the ordinary microscope); dark-field microscopy is required.

The black rat, Rattus rattus, reached Britain and Europe by, at the latest, the 12th century AD, and probably brought leptospirosis with it. It was later supplanted in temperate climates by the brown rat, Rattus norvegicus, which is also a carrier of leptospirosis.

Adolf Weil

The disease was first described by Larrey in 1812 amongst Napoleon’s troops at Cairo. The multisystem disease with jaundice and renal failure was first described by Adolf Weil in 1886 Professor of Medicine at Heidelberg University –‘an acute infectious disease with enlargement of spleen, jaundice and nephritis’. Adolf Weil name is still attached to a serious form of leptospirosis called Weil's disease, traditionally attributed to rat-transmitted infection caused by the serovars icterohaemorrhagiae and copenhageni.

Leptospira is derived from a Greek word ‘leptos’ meaning thin and a Latin word ‘spira’ meaning coiled. It is the most ancient spirochete that can live both in the animals and free in the environment.

The causative organism was discovered by Japanese workers who saw spirochaetes in the liver of a guinea pig that had been inoculated with blood from a patient with Weil’s disease. Inada and Ido detected both spirochetes and specific antibodies in the blood of Japanese miners with infectious jaundice. They called the organism Spirochaeta icterohaemorrhagiae.

Captain Adrian Stokes, who had studied leptospirosis among Allied troops on the Western Front during the First World War, showed that leptospirosis and yellow fever were distinct diseases. Unfortunately, he paid for this discovery with his life, dying of yellow fever in 1927.
History of leptospirosis