Tick-borne Diseases: Lyme Disease by Dr. Carter

Following the lead of our colleague, Dr. Miller, we will take a closer look at Lyme disease, our area's most common tick-borne disease. Lyme disease (named for the Connecticut town) has been around for over a century but did not gain public notoriety until the 1980s. The Northeastern US and upper Midwest represent disease “hotspots,” but with warming temperatures, the disease is spreading. While we see scattered cases throughout our clinic's areas, the Goose Lake region especially represents a regional/local hotbed. Lyme disease is caused by a bacterium, Borrelia burgdorferi, which is transmitted by Ixodes ticks, in our area better known as the deer tick.

Map of the State of Illinois Canine Lyme Disease Prevalence for 2014. (CAPC)

Lyme disease, or Borreliosis, while also a well-known human disease, manifests itself differently in our canine patients. Greater than 90% of dogs who are infected with the organism are not “sick” because of it and are asymptomatic. In dogs, the disease may not manifest itself for weeks to months after infection and they may present with signs of arthritis or perhaps a fever. Fortunately, symptoms of the disease respond quickly to a course of appropriate antibiotics. Although rare, the most serious potential long-term effect is kidney disease. Due to this potential risk, in some cases we may recommend a urinalysis be checked to look for any possible indications of kidney involvement. Lastly, while cats may become infected with the organism, they appear more resistant to its effects, do not develop clinical signs and currently, the disease is not regarded to be of clinical concern in our feline patients.

As noted earlier, the deer tick transmits the bacterium, causing infection. There are three life stages involved: larvae, nymph and adult, that utilized various-sized 'hosts' for their feeding (blood sucking!). These hosts range from small (white-footed mouse) to large (dogs, deer, humans) depending on the life stage of the tick. Not surprisingly, the mouse and deer are quite prevalent in our area. Whit the tick feeds on its host, it requires a minimum of 48 hours to pass the bacterium, thus, if the tick is removed within 48 hours of attachment, the bacterium cannot be transmitted and the host will not get the disease.

Diagnosis of Lyme disease is confirmed through blood testing. When performing our recommended yearly heartworm testing, the test also checks for three tick-borne diseases: Lyme, Ehrlichiosis and Anaplasmosis, the latter two being less common in our are. Remember, simply having a positive result does not constitute illness. However, if the patient is exhibiting joint pain and maybe a fever, we may prescribe a course of antibiotic therapy. Treatment does not eliminate the organism, it will remain in a low latent state, similar to the 90% of infected dogs who do not experience illness.

Tick control is the hallmark of Lyme disease prevention. Ticks can be active year-round and continuous protection is recommended. We carry and utilize monthly topical applications or a new chewable monthly medication, all of which kill ticks before they can transmit disease. In addition to these products, vaccination offers additional protection against Lyme disease. The vaccine inactivates the bacterium within the tick. While we do not vaccinate ever canine patient, it is recommended for patients who reside in regional hotspots, those individuals whose lifestyle is higher risk such as hunting dogs, or individuals who travel to other geographical hotspots such as Wisconsin.

Remember, prevention is the key to protecting both our canine companions AND their human friends, as we take to the woods and fields in our area!

Click here to find more information about CAPC prevalence maps for pet parasites.