Certain dogs have a higher exposure risk based on their lifestyle and geographic location.
dog receiving a vaccine
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The world of canine vaccines is divided into two categories: core and noncore. Core vaccines are recommended for all dogs and include canine parvovirus, distemper, canine hepatitis, and rabies. Recommendations for noncore vaccines, on the other hand, are based on a dog's exposure risk and typically consider their lifestyle and geographic location.

The canine leptospirosis (lepto) vaccine belongs to the latter category and is an important consideration for every dog owner. That's because in addition to having serious consequences in dogs, leptospirosis is zoonotic, meaning it can spread from pets to their people. In fact, it's one of the most common zoonotic diseases in the world.

Deciding whether your dog needs the lepto vaccine ultimately comes down to a conversation between you and your veterinary team. However, Laura Bailey, DVM, co-owner of Bridges Professional Park Animal Hospital in Morehead City, N.C., is here to help sort through what to expect.

Do All Dogs Need the Leptospirosis Vaccine?

"Noncore" is not synonymous with "not important," so don't immediately dismiss the lepto vaccine based on its categorization. The disease can cause kidney failure, liver failure, severe lung disease, and bleeding disorders and can be fatal. Instead, you should talk with your veterinarian to determine your dog's exposure risk.

Leptospirosis is a disease caused by an infection with Leptospira bacteria. According to Bailey, Leptospira has multiple serovars, or forms, that dictate where it can be found and which species carry it. "Rodent urine, bodies of water, livestock, wildlife, and even dirt can be contaminated with Leptospira bacteria," she explains. "Warm, moist climates are also over-represented when looking at areas of high infection rates."

Leptospirosis can be transmitted to dogs when their mucous membranes (e.g. nose, mouth) or skin openings (e.g. cuts, wounds) come into contact with infected urine, soil, or water. They can also contract the disease by eating or being bitten by an infected animal.

Bailey says that your dog's lifestyle is an important consideration when determining whether your dog should receive the leptospirosis vaccine. She notes that your dog is at a greater risk of disease if they:

  • Live on a farm
  • Get into outside trash
  • Hunt small mammals
  • Hike or swim regularly

However, Bailey says that even small breed dogs who mostly live indoors or in urban environments run the risk of exposure. "In fact," she continues, "some reports indicate that small breed dogs make up the majority of hospitalized leptospirosis cases due to their lack of vaccination. These pups can be exposed in their own backyards by drinking from a contaminated puddle or by encountering an infected rodent or other wildlife."

Still, there are some cases in which Bailey wouldn't necessarily recommend the vaccine. These include dogs with little to no risk of exposure and dogs with a history of vaccine reactions or some autoimmune diseases.

Your dog's veterinarian, who knows your pet's specific health history and lifestyle, is in the best position to help you decide if your dog is a good candidate for the lepto vaccine.

How Effective is the Lepto Vaccine?

The leptospirosis vaccine isn't 100 percent effective at protecting dogs from disease. Bailey explains that the current vaccines on the market typically target the four most common Leptospira serovars. "This means that there can be breakthrough infections," she adds, "especially if a dog is exposed to a serovar not covered by the vaccine."

Side Effects of the Lepto Vaccine in Dogs

Bailey says that vaccine technology has significantly improved over the last decade and that allergic reactions are far less likely than before. However, she notes that vaccine reactions and allergic reactions can happen with any pet receiving any vaccine. "Allergic reactions typically involve gastrointestinal symptoms or facial swelling but can be more severe," Bailey explains. If you see signs of an allergic reaction in your dog following vaccination, immediately contact your veterinarian.

"It's not uncommon for animals to experience side effects like soreness, mild inflammation or swelling at the injection site, along with slight lethargy," Bailey adds. "These symptoms aren't specific to this vaccine and are usually not present for more than 24 to 48 hours."

As unpleasant as these symptoms may sound, Bailey says the majority of vaccine side effects are mild when compared with the potential effects of leptospirosis on pets and their owners.

Leptospirosis Vaccine Schedule for Dogs

All dogs need two initial doses of the lepto vaccine. According to guidelines from the American Animal Hospital Association, the second dose should be administered 2 to 4 weeks after the first dose, which can be given as early as 8 or 9 weeks of age. If the dog remains at risk of exposure, they should receive a single dose one year after completing the initial two-dose series and then annually thereafter.

How Much Does the Lepto Vaccine for Dogs Cost?

The price of the leptospirosis vaccine varies by veterinary clinic but tends to cost between $20 and $30. You can call your veterinarian to find out the exact cost for your pet before making an appointment.