Does my pet really need the Leptospirosis Vaccine?

Leptospirosis Vaccination

Recently the American Veterinary Medical Association and American Animal Hospital Association has designated the Leptospirosis vaccination as a core vaccine for any dog or puppy over 12 weeks of age.  This is due to the severity of disease that can occur to not only the pet but also the potential to spread to the pet owner.  

What Is Leptospirosis?

Leptospirosis is a bacterial infection that can cause serious illness in both pets and people. The bacteria are spread through the urine of infected animals (pets and wildlife).  It was used to be thought to only thrive in moist environments—like puddles, ponds, irrigation ditches, or even damp soil, but has been seen more in dry, high altitude environments lately.  This may be due to the increased development of land for human use, causing more raccoons and other wildlife hosts to inhabit new areas, raising the risk for disease spread (AAHA).  What was once a disease that was considered only a possibility in at-risk dogs (those whose lifestyle was more amenable to hunting/fishing/hiking) is now being seen in urban pets that are not vaccinated. 

Once infected, dogs can develop severe symptoms like vomiting, fever, lethargy, kidney or liver failure, and in some cases, it can be fatal. Even more concerning, lepto is zoonotic, meaning it can be passed from pets to humans. That makes vaccination a matter of public health, not just pet health. 

How the Leptospirosis Vaccine Works

The leptospirosis vaccine helps your dog’s immune system recognize and fight off several of the

most common strains of the bacteria.

● Initial vaccination involves a two-dose series, about 2–4 weeks apart, starting anytime after 12 weeks of age.

● After that, annual boosters are recommended to maintain protection.

● The vaccine is safe for most dogs, with side effects typically being mild, think temporary soreness at the injection site or slight lethargy for a day.

Does My Pet Really Need It?

Here’s the short answer: If your dog goes outside in Utah, there’s a good chance they’re at risk. Even if they don’t swim or hike, other common scenarios still expose pets to leptospirosis:

● Sniffing or licking puddles on walks

● Playing in yards where wildlife may have urinated

● Visiting boarding facilities, daycares, or groomers with other dogs

Even small or senior dogs benefit from protection, especially since older pets may be more vulnerable to severe complications if infected.

Common Questions We Hear From Utah Pet Owners

“My dog never leaves the backyard—do they need the vaccine?”

Yes. Leptospirosis has been found in suburban areas, and wildlife don’t respect fences.

“Is it really that common in Utah?”

It’s more common than people think, and under diagnosed. We’ve seen a noticeable uptick in

potential cases, particularly after wet winters or spring runoff.

“Is the vaccine safe for small or older dogs?”

Generally, yes. Vaccines have advanced with much less common adverse reactions.  We carefully assess each patient and adjust the vaccine schedule or timing based on individual needs.

Ready to Protect Your Pet?

If you’re not sure whether your dog is protected against leptospirosis, give us a call or schedule a visit. We’re happy to talk through your pet’s lifestyle and determine whether the vaccine is a good fit.