An allergen called leptospirin was originally used on pigs in an intradermal test to diagnose leptospirosis.Comparative studies on human populations, pigs and cattle, equines and canines have shown a correlation between positive serologic reaction to leptospirosis and a positive intradermal test.In addition, the intradermal test may be positive even in the presence of strains of saprophyte leptospires such as L. biflexa.The test positive intradermal is objectified by erythema at the point of inoculation [59].However, antibodies can be found in the blood following the injection of the allergen by up to 6 to 8 weeks after the intradermal test.For these reasons, the intradermal test is not used to diagnose leptospirosis infection