Leptospirosis in Dogs - Current Status  (Last Updated: 19-Jul-2001)

In: Recent Advances in Canine Infectious Diseases, Carmichael L. (Ed.)
International Veterinary Information Service, Ithaca NY (www.ivis.org), 2001; A0112.0701
P. L. McDonough

Department of Population Medicine and Diagnostic Science, Diagnostic Laboratory, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.

Introduction

Leptospirosis is a bacterial disease caused by pathogenic members of the Genus Leptospira. The disease occurs worldwide in numerous animal hosts, including the dog. The canine disease presents as an acute infection of the kidney and liver and, sometimes, as a septicemia. Chronic kidney disease is a common sequel of infection and abortions may occur in pregnant dams. Because many aspects of the infection are poorly understood, there is the possibility that the disease in dogs may go undiagnosed. Recent events in the Northeastern USA have placed leptospirosis at the top of the list of differential diagnoses for dogs that present with signs of acute liver and/or kidney disease. While diagnostic methods have improved over the years, most are relatively insensitive. Information about leptospirosis is further complicated by major changes in the taxonomic classification of the Genus Leptospira. If the changing patterns of disease in dogs are to be understood, it is necessary to recognize that this re-emerging infection is influenced by the cycles of infection in wildlife, where the infection may spill over into domestic animal populations. Other factors affecting the pattern of disease in dogs are the vaccination history and antibiotic usage. This monograph on canine leptospirosis highlights recent findings on the disease in dogs, and it challenges veterinarians to learn more about this serious disease which affects both animals and man.

Leptospira - Environmental Survival, Microbiology, and Taxonomy
Leptospira do not multiply outside of the host and their survival depends on environmental conditions in which leptospirae are found, e.g., soil and water conditions. Leptospira are highly susceptible to drying and to pH changes - pH<6 and pH>8 are inhibitory; temperatures < 7 - 10