Lyme Disease in Dogs

January 1, 2017October 17, 2023 Lambert Vet Supply

“I’ll get you, my pretty!”

The villain in this case bears no resemblance to the Wicked Witch and at a near microscopic size it would appear very harmless, but don’t underestimate its power. The Ixodes tick, commonly known as the deer tick, is the carrier of one of the most dreaded pet diseases for dog owners-Lyme Disease. Precisely, Lyme Disease is caused by the spirochete (corkscrew-shaped) bacteria Borrelia burgdorferi and is transmitted to dogs, humans, birds and other mammals by the nymph and adult stages of the Ixodes tick. Despite the health risks it presents, Lyme Disease can be successfully treated and prevented for most dogs with proper tick intervention.

A long and short history

Lyme Disease or Borrelia burgdorferi is believed to have a long, infectious history, but really did not gain much attention in America until the mid 1970s when a doctor recognized it in a cluster of children near Lyme, Connecticut; hence its name. It was recognized in Europe a century earlier.

To get Lyme Disease, a dog or person has to be bitten by a tick infected with bacteria. An Ixodes tick will go through three hosts and four different stages in its two-year life cycle, but to carry the bacteria it most likely sucked blood from an infected deer mouse. Animal researchers believe it takes from 12 hours to 48 hours for the tick to inject the bacteria into the dog’s blood and introduce the infection. Through the bite of the infected tick, Lyme Disease creates a condition that causes arthritis and lameness.

Basically, Ixodes ticks, like all ticks, are really tough creatures that can survive through hard winters, a lack of hosts and other factors by going dormant until the temperature or their circumstances improve. Once that happens, they will again be looking for hosts to feed on, partners to mate with, and reproducing their species.

Who gets it? A lot of creatures

Dogs who spend more time outside or live in certain geographical regions of the United State experience a greater risk of getting Lyme Disease. The highest concentrations of Lyme Disease happen in the northeastern, mid-Atlantic and upper Midwest states with small pockets in northwest California and Mississippi. According to the 2015 Clinical Veterinary Advisor manual, in 2012, 96 percent of human cases were from 14 states also located in the areas listed above. According to the Cornell University/Baker Institute for Animal Health web site, Lyme Disease is now the most common arthropod-borne disease for humans and one of the most common in dogs.

Basically, outdoor pets or animals that share fields with mice and deer are at higher risk of being bitten by the affected tick. A pet that receives no tick protection and spends significant time outside is a strong candidate for many parasitic illnesses, with Lyme Disease being one. Certain dog breeds like Labradors, Golden Retrievers and Shetland appear more disposed to get Lyme Disease, too.

Surprisingly, some wildlife mammals and birds do not get Lyme disease, but act as reservoirs for tick infection so the disease is always incubating.

Despite Lyme Disease’s infamous reputation some good news exists. According to research done by the Cornell University/Baker Institute for Animal Health, the proportion of infected dogs that develop Lyme Disease is far smaller than it is for humans. Of 75 percent of dogs exposed to infected ticks in high-risk areas, only about 5 percent of those exposed will actually develop clinical signs attributed to Lyme Disease.

Symptoms and signs along the way

The appearance of Lyme Disease in humans and dogs differs greatly. Humans will develop a rash at the point the tick attached itself along with flu-like symptoms, high fevers and other severe reactions. The devastating chronic stage Lyme Disease presents in humans is not seen in dogs either.

Ironically, affected canines may present no symptoms of Lyme Disease. Dogs do not get a rash. Some dogs may show signs of joint pain and fever about two to five months after the bite, but many will not. Some may have swollen lymph nodes, but not the heart and neurological problems as humans do. For dogs with more obvious signs, veterinarians will find warm, swollen painful joints and fevers 103-106 F. Lameness can come and go in one or more limb. Painful joints may lead to depression and lethargy if dog fears moving will cause pain. In rare cases, some later stage human conditions have also appeared like heart blockage, kidney failure, and neurological changes like seizures, aggression, and other behavior changes.

Nailing down the diagnosis

Veterinarians will consider four things in determining if Lyme Disease could be involved-1) evidence of natural exposure; 2) clinical signs consistent with borealis; 3) consideration of other health issues with the same symptoms, but not Lyme; and 4) a dog’s response to treatment.

Dogs that have spent time in known Ixodes tick infested geographic areas would be at a greater risk for acquiring Lyme Disease. Those who have not been in such regions are far less likely to have been exposed. A vet will also look for lameness, joint soreness and fever and weigh these against other conditions and infections that are not Lyme Disease. Last, if the veterinarian determines to take a standard treatment course for Lyme Disease and the dog responds well, it could or could not indicate the disease’s presence. The response to treatment could still be other things since other medical conditions can cause lameness and other Lyme Disease symptoms.

One or two of these criteria are not usually enough to confirm the presence of Lyme Disease so most likely a veterinarian will use several medical tests to get a better idea of the situation.

1-2-3 testing and more

A veterinarian will use a blood sample for a SNAP-4Dx Plus test to check for six vector-borne diseases, including heartworm, Lyme, and four other tick-produced conditions. If the test is positive for Lyme Disease, the vet will probably call for a Complete Blood Count-CBC and serum biochemistry profile to check on the dog’s overall health. As a side note for anyone testing for Lyme Disease many years ago, the new tests are not skewed by vaccination. They only show positive for natural infections.

A vet may also decide to get an x-ray of limb(s) to check for arthritis as well as an abdominal ultrasound and chest x-rays to rule out other things.

A course of treatment

If testing indicates Lyme Disease is present in a dog, the vet will prescribe antibiotics, primarily doxycycline and amoxicillin for four weeks to try and eliminate the carrier state of the infection. The duration of treatment is warranted because of the very slow multiplication of the borealis organism.

The vet will also add palliative/supportive care to resolve fever and lameness. Some dogs with Lyme Disease-diagnosed arthritis need more than antibiotics so a course of corticosteroids treatments may be prescribed.

Often long-term antibiotic maintenance is needed if Lyme Disease flares up again in a dog or another exposure brings the disease back.

Keeping an eye on it – monitoring: Affected dogs will continue check-ups at six-month intervals in most cases. If the kidney/urinary tract is involved, veterinary visits will probably be scheduled every three-six months.

No magic wand needed – prognosis and outcome: The prognosis is generally good for Lyme arthritis-afflicted dogs. Most canines respond immediately to antibiotics and palliative treatment without recurrence.

However, the prognosis is guarded to poor if kidney problems result from Lyme Disease.

Doing the homework pays off – prevention

For dog owners who wish to stop the transmission of Lyme Disease, some simple steps can keep it at bay. Regular application of topical tick parasiticides and use of tick collars provides an easy first defense. Another is to keep a constant, daily lookout of tick infestations on your dog. Checking out its fur and skin after outside activity will help catch all ticks before they can implant for a meal on a dog or cut off the blood sucking quickly. Insect control yard spray can be used in wooded and weedy areas, too, as a way of eliminating more ticks that are not removed through regular yard maintenance.

Tick prevention and control is paramount to stopping the spread of the tick responsible for Lyme Disease. Dog owners can keep grass moved, remove weeds and use outside tick sprays and such to inhibit tick proliferation. Keeping the deer tick and all ticks at bay can be accomplished with oral medicine, spot-on topical treatments, yard sprays, and, vaccination. Pet owners have many choices for flea and tick treatment and control for their dogs.

Some pet owners may prefer getting their furry friend vaccinated with a lyme disease vaccine. Be sure to consult with your veterinarian about the effectiveness of this option for your animal. Some controversy does exist because the most serious forms of Lyme disease in dogs have an immune-mediated pathogenesis. This means some researchers feel introducing the borealis bacteria to a dog’s system ultimately hinders its immune system and can let other diseases get a foothold. However, many dogs have been successfully vaccinated against Lyme Disease. A definitive answer on this matter has not been reached yet.

Small, but mighty the Ixodes tick infected with Borrelia burgdorferi bacteria proves a worthy opponent, but dog owners can claim victory without any magic tricks. A lot of close supervision and attention to detail will keep Lyme Disease from being a wicked curse for their dogs.