How to Prevent, Detect, and Treat Lyme Disease
When the weather gets warmer and your pets spend more time outside, there is a greater chance that they will come into contact with ticks.
Aside from being a painful pest, ticks can also carry Lyme disease. Read our article to discover more about this disease and how to both prevent and detect it.
The History of Lyme Disease
Lyme disease is an infection caused by the bacteria Borrelia burgdorferi, which is spread by ticks. In the Midwest, it is transmitted primarily by Ixodes scapularis, also known as the deer tick or black legged tick. While the DNA of the bacteria has been found in mummies thousands of years old, Lyme Disease was not recognized until the 1970’s when it was first diagnosed in the neighboring towns of Lyme and Old Lyme in Connecticut.
Ticks can be infected with Borrelia burgdorferi bacteria at any point during their life cycle, however, it must first attach to and feed on an infected host to contract the bacteria.
After infection, while the bacteria are in the midgut of the tick, a protein on the surface of the bacteria is activated which allows the bacteria to stick to cells in the midgut of the tick. When the tick then attaches to your dog, the blood meal deactivates the first “sticky” protein and activates a second protein which causes the bacteria to migrate from the midgut of the tick to its salivary glands where it sticks to the salivary gland cells. The host (e.g. the dog) is then infected through the tick saliva. This is why a tick must stay attached to the host for at least 24 - 48 hours in order for the bacteria to be transmitted.
After infection, it can take several weeks or months for clinical signs to develop, if they develop at all. In 90 – 95% of dogs exposed to Borrelia burgdorferi, clinical signs never develop or are mild and self-limiting and resolve within a few days. Clinical signs in the 5 – 10% of dogs who are significantly affected include lameness that shifts from one leg to another, fever, enlarged lymph nodes, and joint swelling. In 1 – 2% of affected dogs, inflammation of the kidneys can result, leading to acute renal failure. Rarely reported disorders include cardiac arrhythmias, inflammation of the eyes, meningitis, and encephalitis.
Since many dogs who are infected with Lyme disease never develop clinical signs, sometimes we do not know a dog has been exposed until they come in for their routine yearly exam.
As part of your dog’s annual exam, we perform a 4Dx test which screens for heartworm disease, erlichiosis, anaplasmosis, and Lyme disease. It is possible for a patient to be positive for Lyme disease on the 4Dx test without having the clinical disease or needing treatment.
If an owner is noticing symptoms such as limping, and there is suspicion of Lyme disease, the 4Dx test will be recommended. Once we have a positive result on the screening test, additional testing is recommended to fully evaluate the severity of disease. Further tests would include full blood work and a urinalysis to evaluate how well the kidneys are functioning as well as checking the patient’s blood pressure to look for hypertension. We also recommend a Lyme Quant C6 Antibody test to measure the number of antibodies that the patient’s immune system has developed against the Borrelia bacteria. All of these diagnostic tools help us determine if a patient truly has an active infection that needs to be treated.
Once we have determined that a patient has an active infection, 4 weeks of treatment with an antibiotic called Doxycycline is started. If there has been kidney damage from the infection, additional treatments may be recommended depending on the severity. For dogs in acute renal failure, we would recommend hospitalization for IV fluids and supportive care. For dogs who are clinically acting normal, we may recommend a diet change, fish oil supplementation (to protect the kidneys), and possibly blood pressure medications (if the patient is hypertensive). Six months after finishing the antibiotic Doxycycline, we recommend rechecking the patients blood work (including the Lyme Quant C6 Antibody test) and urinalysis to verify success of treatment and monitor any kidney disease that may have been present.
Unfortunately, once a patient has been infected with Lyme disease, it is still possible for her to be infected again, since previous infection does not provide resistance against future infections. There are two main measures recommended for prevention of Lyme disease in dogs: vaccination and tick prevention.
A vaccine for Lyme disease is available, but in our area, it is considered to be a “lifestyle” vaccine rather than a “core” vaccine for dogs. This means that your veterinarian will recommend the vaccine for your dog based on its risk of exposure. Dogs who are at higher risk include hunting dogs, those who live near tall grass or wooded areas, and those who visit these areas. As more cases are noted in our clinic, we are recommending this vaccine for more dogs in our area.
Limiting tick exposure is also important in preventing Lyme disease. We recommend monthly tick prevention be given year round, since ticks can be active in temperatures as low as 32oF.
Did you know that in Chicago in January 2019, there were 16 days when the temperature was 32oF or higher? And in February 2019, there were 17 days when the temperature was above freezing! There are several products available in topical and oral form which protect our patients from both ticks and fleas. Ask your vet which product may be best for your pet. Even if tick prevention product are used, check your pet thoroughly for ticks after visiting wooded areas. Common sites to find ticks on dogs include the face, ears, and front legs, however, they can be found anywhere on the patient. If a tick is found, it should be removed immediately using a tick spoon. These are available from your local pet store.
Lyme disease is becoming more common across the U.S. as the ticks which spread this disease migrate to new areas. Since the number of cases at our own clinic has increased in recent years as well, preventive measure are becoming more important. Vaccination and tick prevention are the best ways to prevent Lyme disease in your pet.
For more information about Lyme disease and ticks, please call us at (708) 758-2400.