what to know about Lyme disease

Lyme disease, which is transmitted by black-legged ticks (also known as deer or ixodes ticks), is a health threat for dogs across the United States. 

Here’s how to identify symptoms, what to know about the Lyme disease vaccine, and how to help your pet. (Even seemingly healthy pets can test positive for Lyme!)

A lesson in Lyme disease

As tick populations migrate, Lyme disease is increasingly becoming a concern in areas that didn’t previously have large populations of contagious ticks.

The basics

Lyme disease is a bacterial disease transmitted to humans and dogs by tick bites from the black-legged tick, Ixodes Scapularis, which is sometimes called a deer tick or bear tick. These ticks carry a strain of bacteria, Borrelia burgdorferi or Borrelia mayoni, that they inject into their host’s bloodstream as they feed.

Lyme disease affects both humans and dogs, although cases in cats are very rare. Once a host is infected, the bacteria travels throughout their body, multiplying and causing irritation, inflammation, fever, and other signs of illness.

The majority of Lyme disease cases in dogs are reported in the northeastern, upper Midwestern, and Pacific coast areas of the United States. However, climate and environmental changes mean that black-legged ticks are rapidly expanding into new areas.

While black-legged ticks spread Lyme, other varieties of ticks can spread diseases like Rocky Mountain spotted fever, babesiosis, and more. You can help your pet and human family by being aware of the threats in your area, using parasite control, and performing regular tick checks to remove ticks as quickly as possible.  

How Lyme attacks

There’s no evidence that dogs (or people) catch Lyme from other dogs (or people). You must be bitten by a black-legged tick carrying the Lyme bacterium to become infected with Lyme disease.

Tick bites spread disease by introducing bacteria, viruses, or single-celled parasites into their host’s bloodstream while they feed. Depending on the disease, contagion can happen quickly or over a few days — which is why removing ticks quickly and safely is so important.

Black-legged ticks are often found in heavy brush, woods, marshes, or on high grasses. Since ticks can't jump or fly, they use their bottom legs to anchor themselves at the tip of grass and plants. They’re alerted by heat and carbon dioxide, and when a dog comes panting by, the tick brushes on and crawls to a comfy spot.

This questing behavior means that ticks are most likely to latch on where dogs touch foliage or tall grass. Common areas include inside and outside pet ears, around eyes, on faces, and under collars. Ticks may also infest skin folds between the front and back legs or settle on tushes, tails, and feet.

Once on their host, male and female ticks attach for a blood meal. Males will roam to find and impregnate feeding females, which drop off when full to lay thousands of eggs and hatch more ticks. 

Spot the signs

Signs of Lyme disease are typically easier to identify in people than in pets. While humans often develop a red “bullseye” rash on their skin, dogs may show no symptoms at all — or they may have symptoms that could also be caused by other diseases.

The only sure way to know if your dog has Lyme disease is to see your veterinary team for specialized tests. These tests can help identify antibodies to the Lyme bacterium in their bloodstream, which is a sign that your dog has been exposed.

Dogs may show Lyme disease symptoms around two to five weeks after a tick bite. Signs can also appear or even reappear at a much later date. 

No appetite: Dogs that won’t eat are usually not feeling their best. With Lyme disease, overall discomfort may suppress their appetite. 

Fever and swollen lymph nodes: These nodes are easiest to see or feel below your pet’s lower jaw, behind their knee, or in their armpits or groin.

Swollen joints, joint pain, and lameness: The bacteria that causes Lyme disease will often target your pet’s joints, making them move stiffly. This pain may affect different joints at different times.

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Untreated Lyme is no joke

A pet with active Lyme disease symptoms needs veterinary care to help manage their illness and improve their quality of life. Untreated Lyme may lead to life-threatening organ failure.

If your dog tests positive for Lyme disease, coordinate treatment with your veterinary team. We can make recommendations based on your pet’s level of illness and pain and evaluate next steps for care.

A cure for Lyme disease?

Lyme disease in dogs is typically treated with a 30-day course of prescription antibiotics. In some cases, pets may need a longer course of treatment or additional therapies to help fight infection and manage pain.

There are no home cures or natural remedies that have proven effective in helping dogs avoid or recover from Lyme disease. Certain supplements may help joint mobility, but they don’t help your pet fight off tick-borne disease. 

How to help your furry pal

There are a number of ways you can help protect your dog from ticks, plus ways to try to help limit their risk from a tick bite.

Know the risk in your area: Deer ticks tend to be in certain regions and prefer certain kinds of foliage. Ask your veterinary team about the parasites that are of top concern in your location.

Regular tick checks: Ticks swell as they feed. A swollen, full tick has spent more time on your pet than one that has just begun their meal. Since a tick typically needs to feed anywhere from 24 to 48 hours to transmit Lyme disease, regular tick checks can help you to find ticks early — potentially preventing severe disease.

Pet parasite protection against ticks: Give your pet vet-recommended parasite control that includes protection against ticks. These preventives come in multiple forms, including chews, topical meds, and varieties that also protect against other parasites as well as ticks. Ask your veterinary team what we recommend for your unique pet.

Lyme disease vaccine for dogs: A two-dose Lyme vaccine for dogs can be effective against preventing severe disease. Vaccine effectiveness can fade over time, so coordinate your pet’s vaccination schedule with your veterinary team.

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