Can Dogs Get Lyme Disease? Risks & Signs to Watch For

Lyme disease in humans has become increasingly talked about in recent years, but did you know that your pet is also at risk? Yes, Lyme disease in dogs is an issue that all pet owners need to worry about — especially during summer months. When the weather is warmer and your dog spends more time outside, their chances of being bitten by a tick and contracting Lyme disease increase.

Though this probably feels a bit alarmist, the risk for your dog may be higher than it seems. One review of almost 12 million canine Lyme disease tests found that not only were 1 million of those cases positive, but the illness may be close to 25 times more prevalent than Centers for Disease Control (CDC) projections have historically suggested. Likewise, experts from the Virginia-Maryland College of Veterinary Medicine at Virginia Tech recently stated that cases of canine Lyme disease have been on the rise.

Why all the fuss? Lyme disease has been known to cause a negative impact to quality of life and, in rare cases, fatalities. It’s also difficult to treat even when discovered quickly. And while checking for ticks is a key step for prevention, the ticks that carry Lyme can be hard to spot. For all these reasons, it’s crucial as a dog owner to become informed and know how to mitigate your pet’s risk.

What is Lyme disease?

Also known as Lyme borreliosis, Lyme disease is an infection caused by a bacterial organism called Borrelia burgdorferi. This bacteria is usually transmitted to dogs and humans via ticks — tiny arachnids (not insects!) that feed on the blood of mammals, birds, reptiles, and even amphibians. It should therefore come as no surprise that Lyme disease in dogs is primarily spread during tick season, which is May through August. Ticks are nevertheless active throughout the year so long as temperatures remain above freezing.

For those pet parents wondering, no, Lyme disease cannot be transferred directly from a dog to a human. That said, a dog could transport unattached ticks, which later attach to humans (just another reason to check both your pal and yourself after time spent outside!).

Here’s another fun fact — Lyme disease gets its name not from the bacteria or the ticks that cause it, but from Lyme, Connecticut where it was first discovered.

Ticks that carry Lyme

Not all ticks are known to carry Lyme disease (though you should still remove any tick you find on your pet). As of 2024, there are only two types of ticks known to carry Lyme bacteria:

• Blacklegged tick — This tick is commonly found in tall grasses. It lives in the northeastern, mid-Atlantic, central, and southern United States and is also found across eastern and central Canada.
• Western blacklegged tick — Residing along the Pacific coast of the US and Canada and some bordering areas, this tick is commonly found in beds of leaves and pine needles. However, it is also known to hide along wooden fences, park benches, and outdoor tables.

Both types of ticks are often called the “deer tick.”

Interestingly, young deer ticks are responsible for most known cases of Lyme disease in both humans and pets. Known as “nymphal ticks” or simply “nymphs,” these ticks are under two millimeters in size and are commonly compared to the size of poppy seeds. They’re so small, many people don’t see them while they’re attached at all, and their bites often go unnoticed.

Accordingly, there is some disagreement among experts over how long it takes for a tick to actually transmit Lyme disease. As Lymedisease.org points out, the CDC states that ticks must be attached to their host for more than 24 hours, but some research studies have shown that “5-7% of nymphs transmitted the Lyme bacteria in less than 24 hours. One paper reported on a case of Lyme disease transmitted after six hours of tick attachment.”

Where is canine Lyme disease most prevalent?

Lyme disease can be found on every continent with the exception of Antarctica. Of course, some areas are notably more at risk than others. In Canada, Lyme disease has been found across all southern areas of the country, with highest incidence in Ontario, Quebec, and Nova Scotia. Dogs who live in these areas are considered to be at greatest risk.

Signs of Lyme disease in dogs

In some cases, a bullseye-like rash appears in the area of a tick bite that could be an early indicator of Lyme disease. Of course, this rash can be tough if not impossible to spot on dogs thanks to all their fur. In most cases, pet owners will not notice any signs of illness in their dog until about two to five months after the Borrelia bacteria has entered the bloodstream. This means that your pup could start showing signs of Lyme disease infection long after their last adventure through tall grass or warm weather has ended.

The most common (and sometimes only) sign of Lyme disease in dogs is sudden lameness which can often appear in one leg and shift to another. Other indicators of canine Lyme illness (but may not be limited to) include:

• Swollen or tender joints
• General limping or lameness
• Fever
• Lethargy or weakness
• Loss of appetite
• Changes in urination
• Mood or personality changes (in some cases)

Rarely, serious issues such as kidney failure can occur. It is at this point that Lyme disease can become life-threatening for your dog. That’s why you need to make sure that you are getting them checked out as soon as you notice these symptoms.

Neurological and heart issues may also be present in some dogs, but are very rare.

Diagnosing canine Lyme disease

A common test that veterinarians use checks your dog for antibodies to this disease. Antibodies are created by the body to fight the organism, and a positive result will show the dog was exposed. If positive, additional testing may be recommended.

Keep in mind that Lyme disease symptoms can be very similar to a wide range of other health conditions. This is why it’s so important to schedule an appointment for your pup as soon as you spot any signs of Lyme and keep your vet informed about their outdoor activity.

Treatment for Lyme disease in dogs

Believe it or not, dogs actually have more treatment options available than humans do for Lyme disease. Prognosis with treatment is also usually good, especially for dogs showing only mild to moderate clinical signs. Depending on your pet’s symptoms and the severity of the illness, your vet will be able to provide several treatment options, starting with medication. This most frequently includes antibiotics that are administered over several weeks.

A persistent infection with a very low bacterial burden may remain, but treatment does significantly improve symptoms. In this situation, long-term monitoring may be recommended by your vet. In more severe cases, progressive joint damage caused by the Lyme bacteria may result in long-lasting mobility issues for your dog, even after treatment has been successful.

Can dog insurance cover Lyme disease?

In many cases, dog insurance or pet health insurance will not cover Lyme disease treatment because it is considered a preventable illness (see more on this below). Trupanion will nevertheless extend coverage to treatment for Lyme disease if your pet is on routine flea and tick preventatives and still got the condition. This is because these preventative treatments help, but they’re not always foolproof when it comes to ticks.

According to Trupanion data, the highest amount paid out in a single claim for Lyme disease was $12,362 (as of 2024). However, because Lyme can sometimes take a while to be properly diagnosed, this does not reflect claims that may be paid out for associated symptoms like limping or urinary issues.

In any case, having a good dog insurance plan in place is a good idea in general for unexpected, non-preventable illnesses. Lyme disease can be similar to a wide range of other health conditions after all, and it’s far from the only risk for your pet when they spend time outdoors. Because you don’t know what exactly will come your dog’s way, you can get peace of mind by protecting them ahead of time.

Preventing Lyme disease in dogs

There are several things you can do to help prevent Lyme in your pet (and yourself for that matter):

• Check regularly for ticks after a walk and keep away from areas where ticks are likely to be.
• Talk with your veterinarian. If you live in a high-risk area, your veterinarian may recommend a vaccine to fight the bacteria that causes Lyme.
• Consider having a professional treat your yard for ticks.
• Use parasite-prevention products that target ticks; sprays, collars, pills/chewables, etc. The effectiveness of these treatments vary, so ask your vet which one may be the best option for your dog.
• If your dog does get diagnosed with Lyme disease, have yourself and any other pets in your household checked. The illness itself is non-transmittable, but carrier ticks can bite more than one victim. They are also often found near other carrier ticks.
• Remove ticks as soon as you find them on yourself or your pet.

How to remove a tick from a dog

Deer ticks, especially nymphal ticks, are incredibly hard to spot. However, their bodies swell as they feed, making them more noticeable. This means that you may be able to find them on your dog's skin if you comb through their fur and look carefully. Though a bit tedious, it’s a good idea to do this every time your dog spends time outdoors.

A tick can latch onto your dog anywhere, but they will most often be found on the underbelly of your animal. Ticks who have only recently hopped onto your pet may be found crawling on the legs or back.

When you do find a tick, you should remove it promptly from your pet regardless of what type of tick it is. You can remove a tick with a special device that you can get from your vet. Removing it without a tool like this may cause you to only get the body or could force partially digested blood back into your dog which could increase their risk of infection. Be careful and if in doubt, consult your vet.