After a recent outbreak in California among under-vaccinated dogs, I’ve been getting questions about Leptospirosis again. Given all of the press about vaccines lately, it seemed like a good time to revisit this old headache.
Leptospirosis, or Lepto, is a bacterial infection that is common in many animals, including humans. In fact, Lepto is the disease that wiped out the local native Americans prior to the arrival of the Pilgrims. During prior colonization attempts from Europe in the early 1600s, infected rats came ashore and spread Lepto throughout our area. Since that time, it has mutated to the point that almost every local animal carries some form of it. So long as it is within its “carrier species”, it doesn’t cause many problems. But, if say squirrel Lepto gets into a dog, it can be deadly.
Lepto is passed in the urine where it can multiply in the environment and survive even freezing temperatures. It has a high affinity for iron within animal’s blood. So, when a dog walks through a spot where an infected animal has urinated, it will seek ways into the body through any little cuts or scrapes on the feet. Once in the body, it will try to set up shop in the liver and kidneys. Once there, the body will try to clear the infection, but the subsequent inflammation can cause short-term liver and kidney failure. In the early stages, this will seem to the owner like a dog that “just ain’t right”. They are lethargic, have poor appetites, and will seem warm from fever. If not caught early, they will typically need ICU-level care, including dialysis. While most dogs survive, I have seen ICU bills ranging from $15,000 to $35,000.
As vets, we suspect Lepto anytime a dog shows signs of liver and kidney disease. We have tests available for Lepto both in-clinic and in more comprehensive forms at our reference labs. We will usually have to rule out other forms of disease in these organs as we await results. So, we will also check imaging like ultrasound and x-rays.
As my title suggests, there is a vaccine for Lepto. Unfortunately, older forms of the vaccine from 30 years ago did have a high risk of causing allergic reactions. As a result, many vets stopped giving the vaccine. However, new forms are extremely safe and have been around for 15 to 20 years. Repeated studies have shown that a vaccinated dog has only a 0.5% chance of contracting Lepto. The outbreak I mention above happened in very high-end daycare facilities around Los Angeles and every single dog that became sick was unvaccinated. So, the debate over the efficacy of this particular vaccination is basically over.
August through December are when the highest number of dogs become infected with Lepto. If your dog is unvaccinated, it will need a series of two vaccines, 1 month apart. Be sure to check with your vet to see if your dog is up-to-date with all recommended shots.