Leptospirosis is an acute infective illness affecting both humans and animals. It is caused by spirochaetes of the genus Leptospira, divided at present in two species: L. interrogans and L. biflexa. Infection may range from subclinical to severe, and include symptoms such as fever, headache, myalgia, meningitis and abdominal pain. Complications such as hepato-renal failure and central nervous system involvement may occur.

Serological testing can be performed from the 7th day following the appearance of clinical signs. The antigen used in the kit comes from Leptospira patoc, a non-pathogenic species, which allows production of a thermoresistant Leptospira group antigen.

The diagnosis of leptospirosis can be made by microscopic examination of a culture medium after inoculation by blood, urine or cerebrospinal fluid. A special medium is available for this purpose.