“Why should I vaccinate my dog against leptospirosis?” This is a question that is asked in veterinary exam rooms across the country. Conscientious dog owners do not want to over-vaccinate their dogs, and above all, they do not want to cause their pet any harm from vaccine side effects. Moreover, some owners are advised by their breeders to avoid the vaccine. How do you make the right decision?
Leptospirosis is a zoonotic disease — a disease that can be passed between animals and people. It is spread by spirochete (spiral-shaped) bacteria in the urine of infected rodents, wildlife and pets. There are more than 200 different strains of leptospirosis, and certain strains appear to prefer certain hosts, like dogs, pigs, raccoons or even rats.
The Leptospira organisms enter the body through mucous membranes or through abrasions on the skin. People and animals can become infected from direct exposure to infected urine, but also through contaminated environment, such as water or damp soil.
A veterinary gastroenterologist communicated the following story to me about this devastating disease. A new veterinary school graduate honeymooning in Hawaii went swimming in a volcanic lake. When he got home, he had a fever, flu-like symptoms and severely bloodshot eyes. The doctors could not diagnose the cause of his illness until he died and was autopsied. They isolated the Leptospira bacteria. The most likely explanation for his death was that wild animals had urinated in the lake. The organisms had infected him through his mouth and eyes or possibly a scratch on his skin.
People and pets are exposed to Lepto while camping or participating in outdoor recreational activities. Drinking or swimming in water that is infected with Lepto is the most common exposure, but wet soil can be contaminated, as well. A city environment will not always provide protection against this serious disease. Rats and raccoons are prevalent in the urban environment, and their urine is in puddles and city fountains and ponds.