There has been a misconception over the years that the leptospirosis vaccine is unnecessary and even dangerous. Some persist with the opinion that the lepto vaccine has a higher risk of causing reactions, and therefore should not be given. I've seen veterinary staff perpetuate this idea, yet when asked what the reaction rate is or any data to support it, they can't give it. I've seen clients come in with sheets from breeders with a big "never give leptospirosis" plastered in bold letters. Such viewpoints over the last 15-20 years has led to a decrease in vaccinating for this disease. And I believe this is a mistake.
Leptospirosis is a bacteria that can be found in numerous kinds of wild mammals. Infected animals shed the organism in their urine, which can contaminate soil and water. Anyone or any animal coming into contacted with these areas can in turn become infected. This is a serious disease, leading to often deadly kidney or liver failure. Humans are as susceptible to lepto as animals, and an infected dog could be a risk for its owners.
Why bring this up now? An article was published a few days ago about an outbreak of leptospirosis in Detroit, Michigan. Twenty cases were recently diagnosed and nine dogs died as a result of the infection. This is not rare, and may be a growing concern. Over the last few years cases of lepto have increased around the country. Personally, I believe that the increase in lepto cases coincides with the decrease in people vaccinating. I also believe that the true rate of infection is much higher, as most vets (myself included) don't think to test for lepto when we have a case of acute liver or kidney disease. In fact, we have historically done such a good job of vaccinating that many vets have never seen a case of leptospirosis, though this may change.
Lepto vaccines are common, easy to give, and available at just about every vet. A few studies have compared reaction rates of the distemper-parvo vaccine with and without lepto components and found the reaction rate to be statistically identical, which means that modern lepto vaccines are NOT more reactive and are NOT an increased risk. And with cases such as the one above, we should be recommending the vaccine MORE and not less.