Do you know these facts about Lyme disease?

by Melissa Evans LVT, CVT, VTS (ECC) for VetCandy LLC

Lyme is a bacterial disease caused by the bacterium Borrelia burgdorferi. It is transmitted by the bite of a tick and commonly affects dogs, horses and humans. Other animals can get Lyme disease, including wildlife, such as deer, but dogs and horses are the most common domestic animals that are infected. Interestingly, cats, even outdoor cats,are almost never affected.

Ticks are known as vectors. A vector is a living organism that doesn’t cause the disease, but which carries infection and transmits disease. Lyme disease is the most common vector borne disease in the US.

It is the Ioxides species of tick that is the main carrier of Lyme disease. Their common name is black-legged ticks or deer ticks. Ticks are found outdoors, usually in tall grasses or thick brush in marshes and woods. They and feed on blood from animals and humans and pass the bacteria into the blood stream. Ticks are not able to fly or jump, but they wait on long grasses and in shrubs for a host to walk by and brush the plant. At that point they climb on to the passing host and find a space of open skin where they can bite the host and latch on.  Ticks are able to attach to any part of the body, but will often attach to legs and armpits on humans. In dogs and horses they often attach around the ears, base of the tail and legs. Most humans and dogs are infected from the bites of juvenile ticks called nymphs. The nymphs are extremely small, smaller than a poppy seed, so you may not even notice they are there. These nymphs are most active in the spring and summer months. Adult ticks are much larger and are more likely to be discovered and removed before being able to pass on the disease. The adult ticks tend to be more active during the fall.

The infected tick must be attached for 1 - 2 days before the disease is transmitted.

What are the symptoms of Lyme disease?

Unfortunately, Lyme diseae is fairly common in dogs. Symptoms include, fever, loss of appetite and lethargy. Lyme disease tends to affect the joints at first causing intermittent lameness as well as painful and swollen joints. If left untreated Lyme disease can damage the nervous system, heart, and the most common injury secondary to joints, the kidneys. Sadly, this leads to kidney failure and is almost always fatal.

Symptoms of Lyme disease in humans are similar, including fever, headache, fatigue and joint pain and swelling. The most common sign of lyme disease in humans is target shaped rash known as erythema migrans. This rash occurs in up to 80% of humans with Lyme disease, but does not occur in animals. It appears at the location of the tick bite within one week of being bit, but can take up to 30 days to appear. IT is usually not painful or itchy. The classic shape is a bulls-eye or target shape, but it may appear as just a circle.

If lyme is left untreated in humans it can lead to nerve pain, shortness of breath and dizziness, extreme swelling of the joints; particularly the knees; and even inflammation of the brain and spinal cord.

How is Lyme diagnosed?

In both humans and dogs, lyme disease is diagnosed by getting a full history. Your doctor or veterinarian will need to know if you and your dog have been anywhere that ticks might be prevalent and will definitely need to know if you have found a tick on yourself or your dog.

Blood tests can be done to test for antibodies against lyme disease. If your veterinarian suspects that your pet has lyme disease, they will likely recommend a 4Dx snap test. This is a quick in clinic test that uses a small amount of blood to test for common tick borne diseases, lyme, anaplasma and ehrlichia, as well as heartworm disease.

Blood tests for humans need to be run at a lab.

How is Lyme treated?

Antibiotics are important to treat lyme disease. Doxycycline is the antibiotic of choice for lyme disease in both humans and dogs. Most dogs need to be on antibiotics for 4 weeks.  In some dogs that have severe illness a second round of antibiotics may be necessary.

The duration of antibiotic treatment for humans may vary depending on age and health status. Once medications are started symptoms tend to resolve quickly, but it is important to complete the course of antibiotics, even if you or your dog seem to be better. Completing all of the medication ensures that the bacteria have been killed and helps prevent antibiotic resistance.

Is Lyme Disease preventable?

Good News! Lyme disease is 100% preventable!

How do you prevent it? Well, the first step is by protecting your pet and yourself. There are two main preventatives for ticks in dogs and your veterinarian will help you decide which one is right for your pet. These preventatives come in an oral form, usually as a chewable tablet, or a topical form, either as a liquid that is placed right on your dogs skin or as a collar. Consult your veterinarian for recommendations.

Humans can use an over the counter bug repellent when they are anywhere there is concern for ticks. It is imperative that you DO NOT use insect repellent made for humans on your dog. The two main ingredients in insect repellent are DEET and Picardin. These are toxic to animals and can cause vomiting, and seizures.

If you are outside with your pet in an area that has the potential for ticks, try to keep them out of the tall grasses and shrubs that ticks like to hang out on. Owners should wear long pants and long sleeves to prevent ticks from having anywhere to latch on. When you get home, check your dog thoroughly for any ticks that could have latched on. Specifically check their feet, ticks like to hide between the toes, around and inside the ears, around the eyes and under the tail. Run your hands along your dog’s body, going in the opposite direction of hair growth to feel for any ticks.

If you find a tick on yourself or your pet remove it immediately. The faster you remove the tick the lower the chance they will pass on lyme disease. Remember, it takes 24-48 hours for the tick to transmit the bacteria. So, if you remove the tick before that time it is unlikely you or your pet will contract lyme disease. There are videos on the internet that will show you the best way to remove a tick, or you can contact your veterinarian. It’s important not to leave any bit of the tick attached, so appropriate removal is critical. If you don’t feel comfortable removing the tick from your dog, be sure to take him to the vet to get the tick removed.

There is also an option for a non-core vaccine for Lyme Disease for your dog. if your dog’s lifestyle supports the need for this vaccine your veterinarian may suggest that he get this vaccine. Check with your veterinarian if you think this may be appropriate for your dog.