Lyme disease is on the rise in Caldwell County, with positive results for 1 of every 46 dogs tested this year. In 2018, the odds were a little lower—1 of 59 were Lyme carriers. As tick-borne diseases continue to surge, ehrlichiosis, with 1 of 66 dogs testing positive, is closing in on Lyme cases. Ticks may be tiny, but their diseases pack a powerful punch, for people and pets alike.
Transmission of Lyme disease
Unlike mosquitoes, ticks don’t bite and run. To transmit Lyme disease, a tick must stay attached to its host for at least 36 to 48 hours to pass along the bacteria Borrelia burgdorferi. Ticks pick up the Lyme-causing bacteria when they feed on infected mice and other small animals, and pass it along when they bite their next victim. Although Lyme disease is the most commonly reported vector-borne illness in the United States, according to the U.S. Centers for Disease Control and Prevention, only one type of tick is responsible for the surge in Lyme disease cases—the black-legged tick. Two black-legged tick species carry the Lyme bacteria, Ixodes scapularis and Ixodes pacificus. I. scapularis prefers the eastern half of the U.S., while I. pacificus enjoys the Pacific coast, particularly northern California. As weather patterns change, ticks and their diseases are becoming more widespread, with cases now seen in all 50 states. Prevention is key to stopping this disease and its serious effects.
Signs of Lyme disease
Ticks are slow to transmit disease, and signs are also slow to appear. A local reaction frequently pops up at the tick-bite site, appearing as a raised, red bump that forms a scab after tick removal. But, clinical disease signs can take two to five months to appear. Signs can be vague and mimic multiple other diseases, but Lyme disease most commonly presents as:
- Lameness, which may shift from leg to leg
- Decreased appetite
- Reluctance to move due to painful joints
- Swollen lymph nodes
Lyme disease can spread to the kidneys and cause a serious condition called Lyme nephritis, although this disease form is estimated to occur in only 1% to 2% of all dogs infected with B. burgdorferi. Once infected with the Lyme bacteria, the kidneys suffer severely and the result is similar to kidney failure. Lyme nephritis causes the kidneys to lose function and can appear in dogs as the following signs:
- Increased thirst
- Increased urination
- Decreased appetite
- Muscle wasting
While standard Lyme disease is rarely serious or deadly, Lyme nephritis has a guarded to grave prognosis and is often fatal, even with aggressive treatment.
Diagnosis and treatment of Lyme disease
Diagnosis of Lyme disease requires several key pieces of information:
- Detailed history
- Tick exposure
- Evidence of clinical signs
- Antibodies to B. burgdorferi in the blood
- Complete urinalysis
Active Borrelia burgdorferi infections can be difficult to verify. Since a pet can test positive for Lyme disease for months or years after being infected, treatment is usually only warranted if signs are seen. Antibiotic therapy quickly reduces the severity of clinical signs, confirming a positive Lyme diagnosis. Occasionally, pain medication is also necessary to reduce the discomfort of swollen joints. Even though signs improve rapidly, continue antibiotic therapy for several weeks to knock the bacteria level down to a subclinical level with no visible symptoms.
Prevention of Lyme disease
Protect your pet from ticks to avoid a number of different diseases, from anaplasmosis and ehrlichiosis to Lyme disease and Rocky Mountain spotted fever, by following these steps:
- Vaccinate your dog against Lyme disease.
- Routinely use a tick preventive product for your pet.
- Check your pet daily for ticks and remove appropriately.
- Trim grass, bushes, and other plant growth short to make your yard unappealing to ticks.
Need help tackling ticks on your pet? Stop by our hospital to discuss the best tick and Lyme preventives for your furry friend.