Laboratorial diagnosis of animal leptospirosis

Leptospirosis is the most widespread zoonosis in the world, but it is more prevalent in tropical than in temperate regions. Its etiologic agent, pathogenic Leptospira sp., penetrates the animal skin through cuts or abrasions, external mucosa (such as the conjunctiva). Clinical signs are variable and unspecific, particularly in animals, mainly in chronic infections, which are often asymptomatic. For an effective control of an infectious disease it is essential a diagnostic test that have high sensitivity, specificity and practicality. In leptospirosis, misdiagnosis is frequent, what can lead to erroneous treatment in cases of acute disease and to the maintenance of the agent in herds, what could determine considering losses. Noteworthy that the natural course of the disease influences directly on which diagnostic test should be chosen, as well as the type of clinical sample that should be collected. The laboratory diagnosis of leptospirosis is challenging, where there is not a highly sensitive and specific test for a reliable diagnosis in animals. This review presents advantages and disadvantages of the current laboratory methods for animal leptospirosis diagnosis considering the differences between affected species and the disease pathogenicity.