Lyme Disease

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Based on an article that first appeared at

If you were to meet Howie with his cute bow tie and his wagging tail, you would never know that one fateful day last spring his mother thought he was on death’s doorstep. When Howie arrived at my clinic he was painful to the touch, had a high fever, had no appetite, and was very lethargic. He had no desire to walk around and we could barely touch him without him yelping in pain. After carefully examining him, my top two differentials were a back issue or Lyme disease. Howie’s owner remembered that Howie had tested Lyme positive at his previous vet a couple of years ago. Since in-house testing shows exposure and not necessarily an active infection, the positive result was confirmed at an outside lab by measuring the Lyme levels in Howie’s blood. Howie was treated with medication and has happily made a full recovery much to everyone’s relief.

Howie was lucky that his Lyme disease presented as soreness with a fever. Although this is probably one of the more common presentations in dogs along with lameness, did you know it can also cause very serious kidney issues as well?

Dog outside with tick

Important Facts About Lyme Disease?

Lyme disease is a bacterial infection known as Borrelia burgdorferi which is spread by the black-legged tick (also known as the deer tick). The disease was first recognized in 1975 when researchers started investigating why so many children were developing juvenile rheumatoid arthritis in Lyme, Connecticut, and several surrounding towns. There is evidence that Lyme disease was present in wildlife all the way back to the late 1800s. Even though we think of deer carrying the deer tick into our backyards, other wildlife such as mice, foxes, raccoons, squirrels, and other species can harbor ticks on their bodies and help unwanted ticks move from place to place.

Most people mistakenly think that if they do not see ticks or if their dog has short hair that it will be safe from ticks. This is not true. The black-legged ticks have four different stages during their life cycle.  One of the life stages of deer ticks can be the size of a pin head and easily attach to a short haired or a light-colored dog without ever being detected.  After the deer tick attaches, and seals itself to the dog's skin, it will begin to feed taking a blood meal that the tick needs to sustain itself.  Studies have also shown that one of the small, undetectable tick life stages (nymphs) tend to be the culprits in tick disease transmission because they are not easily detected as the larger adult tick life stage.  If the tick is carrying B. burgdorferi, this bacteria will be transmitted to your dog while the tick ingests the blood meal. On average it takes about 24-48 hours for the tick to pass Lyme disease to your dog. 

Lyme disease presents with a variety of clinical signs in dogs. Your dog may contract the disease but never show clinical signs, they may get a fever and have swollen or painful joints, have shifting leg lameness, stiffness, lethargy, or anorexia. In extreme cases Lyme disease can affect the kidneys and result in fatal kidney failure.

Does My Dog Have Lyme Disease?

So how can you tell if your dog has Lyme disease? Take your dog to the vet! You may suspect Lyme disease in your dog if you see some of the above-mentioned signs, but most of those clinical signs can be related to other non-Lyme-related diseases as well. Most veterinarians in the Northeast test dogs annually for Lyme disease. Most veterinarians in the area use an in-house test that looks for heartworm disease, Lyme disease, Anaplasmosis, and Ehrlichia. The three diseases (Lyme, Anaplasmosis, and Ehrlichia) are found in many parts of the United States including the Western and upper Midwest States. 

So what does a positive result mean, and what do you do about it?  If your dog tests positive for Lyme disease it means that they have been exposed to B. burgdorferi. What your veterinarian does with that positive result will vary. Your veterinarian may recommend checking your dog’s urine for protein, which can be an early sign of Lyme disease affecting the kidneys. They may recommend sending out additional blood work to a laboratory to test the levels of the bacteria in their blood and consider whether your dog should be treated, or to monitor your dog for clinical signs of Lyme disease and treat only if clinical signs present.

Dog outside with tick spray

How Do I Prevent Lyme Disease In My Dog?

The most important thing you should ask yourself is how do you prevent Lyme disease?  The best preventative for most all tick-borne diseases (that we commonly see in the United States) is to use flea and tick prevention. Not all flea and tick preventatives are created equally though. You want something that will repel ticks or kill them before the 24-hour mark when they attach (remember it takes 24-48 hours to transmit tick-borne pathogens). It is often tempting to purchase something you see at the store, but I strongly recommend consulting with your veterinarian. Veterinarians can help guide you to products that will give your dog the best protection. Since there are so many choices out there, tap into your veterinarian’s knowledge before making a decision!

Even though Lyme disease is well known to people who live in many parts of the United States, it is important to remember to protect not only yourself but your dog as well. This means using appropriate tick preventatives  and testing if you have been in an area that has ticks. Just because you do not see a tick or your dog is not showing any clinical signs of Lyme disease does not mean that they may not be infected with the Lyme disease bacteria. It is better to be proactive and take steps to prevent tick diseases from being transmitted to your dog than to watch your best friend suffer from the clinical signs of the disease.

Howie is doing wonderfully. It is possible that the Lyme disease will rear its ugly head again; but through careful annual monitoring and using preventive care, we will hopefully prevent that from happening again.