|Ellis, W - VET RES LAB, N. IRELAND|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: August 1, 1996
Publication Date: N/A
Interpretive Summary: Leptospirosis is an important cause of disease in domestic animals throughout the world. The disease in livestock is most often associated with abortions, stillbirths, and acute illness and death in young animals. Animals with leptospirosis shed the organism in their urine and can infect humans that come in contact with animal urine. Diagnosis of the infection is challenging and requires coordination of efforts between the producer, the veterinarian, diagnostic laboratories, and reference laboratories. The primary method used to control leptospirosis is vaccination with inactivated whole-cell vaccines. Vaccines must be formulated based on the types of leptospirosis which occur in the region. We have prepared a state-of-the-art review of the standard methods for the diagnosis of leptospirosis and the preparation of leptospiral vaccines. This review will be published as a chapter in the Office International des Epizooties (OIE) Manual of Standards for Diagnostic Tests and Vaccines. This manual is used as the international standard and the methods described are used in the establishment of international trade agreements. This chapter will be used by animal health regulatory officials in the United States and abroad, by diagnostic laboratory personnel, and by veterinary biologics companies.
Technical Abstract: Laboratory diagnostic procedures for leptospirosis fall into two groups. The first group consists of tests for the demonstration of leptospires or their genetic material in animal tissues or body fluids. The second contains the tests for antibody detection. The selection of tests to be carried out depends on the purpose for which a diagnosis is to be made and the resources available. Isolation of leptospires from or their demonstration in the internal organs and body fluids of clinically affected animals gives a definitive diagnosis of acute clinical disease. Isolation from the kidney, urine, or genital tract of animals without clinical signs is diagnostic only of a chronic carrier state. Isolation of leptospires from clinical material and identification of isolates are time consuming and are tasks for specialized reference laboratories. Demonstration of leptospires by immunochemical tests is more suited to most laboratory situations. Genetic material of leptospires can be demonstrated in tissues or body fluids using a variety of assays based on the polymerase chain reaction. Serological testing is the most widely used means for diagnosis of leptospirosis, and the microscopic agglutination test is the standard serological test. Vaccines for veterinary use are suspensions of one or more serovars of Leptospira spp. inactivated in such a manner that immunogenic activity is retained. Vaccines may contain suitable adjuvants.