Tick-Borne Diseases: What every dog owner should know

Spring is finally here! April is Prevent Lyme Disease in Dogs Month, making this the perfect time to discuss tick-borne diseases in dogs. These are diseases spread by tick bites. There are several different diseases that ticks carry. For this blog, we will mention three that are common: Lyme, Ehrlichia and Anaplasmosis.

These diseases are carried by specific species of ticks and are transmitted when the tick feeds. During feeding, the microorganisms that cause disease are literally spit into the bloodstream of the host animal. The time it takes for this to happen varies, but it can take less than 16 hours of a tick being attached.

What are the signs?

Once a dog has been infected with these organisms, they may not show signs of illness at all. This is called a subclinical infection. If signs of illness do begin to show, it may not be until months after infection. The signs can be non-specific, in other words, there is no symptom unique to the disease. The bullseye rash on the skin is something many people think of as a distinguishing characteristic of Lyme in humans, but dogs do not get this lesion.

Lyme disease in dogs can cause lethargy, lack of appetite, fever, joint pain or cause damage to the kidneys. Similar signs can happen with Ehrlichia and Anaplasmosis. With these two diseases there may also be damage to platelets, the blood cells responsible for blood clotting. Other signs of tick-borne illness include vomiting, diarrhea, coughing, neurological signs, eye problemsand bruising.

How do I know if my dog is infected?

Because dogs infected with tick-borne diseases may show no or non-specific signs, veterinary diagnostics are important. For the three tick borne diseases listed above, there is a convenient and affordable screening blood test that is available and can be run either at a veterinary clinic, taking about ten minutes, or sent to a lab with results typically in 1-2 days. This test is generally used for screening because it tests for antibodies, rather than antigen.

Antigen is the actual disease. Antibodies are the body’s defense mechanism and are formed when the body encounters something that shouldn’t belong, such as a virus. Sometimes, antibodies can clear an infection without the need for any other therapy. These antibodies continue to circulate in the blood, ready to fight again if needed.

This is an important concept when it comes to the screening test. If positive, it does not mean active infection is present, only that at some point there was antigen present and the body created antibodies. A positive test shows exposure rather than active infection. If your pet tests positive, they may continue to test positive for life because they created antibodies.

What happens if my dog has a positive screening test?

If your pet does have a positive screening test, it is important to follow up with your veterinarian to determine what steps should be taken. Specific blood or urine tests may be recommended. Running annual baseline bloodwork and urine tests is also a good idea. Annual tests, similar to annual exams and lab-work for humans, can help to detect changes early. Detecting changes early can allow earlier treatment or help with anticipating future medical needs for chronic illnesses, ultimately helping pets to have a higher quality of life for a longer duration. For tick-borne illnesses, this can indicate a need for treatment before the disease becomes clinical.

What is the treatment for these diseases?

If treatment is needed, it consists of a month-long course of an antibiotic for most dogs when the infection is caught early. Some dogs will require more intensive care depending on the clinical signs they are showing. Hospitalization, fluid therapy and various medications to help with symptoms (vomiting/diarrhea/appetite) may be required as supportive care while the dog is fighting infection and recovering.

How do I keep my dog from getting sick?

While it is possible to treat these infections, it is always much easier to prevent infection in the first place! The solution is simple, a good tick prevention plan for your pet.

Ticks are commonly thought of as a summer problem, but there are species of ticks active all year round. Some of these ticks are smaller than a pin-head and are missed during routine tick checks. Many positive testing pets not on prevention never had a tick found, even with owners diligently performing tick checks. Using an effective prevention year-round is critical to preventing exposure!

There are many prevention options available. Some help to repel ticks, others kill ticks after they bite, but before the tick has enough time to spread infection. There are so many options: topical liquids, chewable tablets and collars—some work well and others do not. Your veterinarian is a great resource to help you choose an effective product. This spring, make a point to bring up tick prevention and discuss what your veterinarian recommends for your individual pet!

Dr. Jennifer Cooke is an associate veterinarian at the Susan M. Markel Veterinary Hospital at the Richmond SPCA. She earned her veterinary license at the University of Florida and completed an externship with the Richmond SPCA. Through this experience, Dr. Cooke graduated with a Maddie’s Professional Certificate in Shelter Medicine.

Dr. Cooke worked in private practice after graduation, then relocated to Richmond to join the Susan M. Markel Veterinary Hospital. Her passion for animal welfare and access to affordable care drove this decision.