Several tick species prevalent in Washington carry diseases that can be transmitted to people and pets. Our Fremont Animal Hospital team provides information about tick-borne diseases in our area and offers tips to help safeguard your four-legged friend.

Lyme disease in pets

Lyme disease is the most commonly diagnosed tick-borne disease in pets and people in the United States, and is most prevalent in the upper Midwestern states, Atlantic seaboard, and the Pacific coastal states. Lyme disease is a bacterial infection caused by Borrelia burgdorferi. Relevant information includes:

  • Transmission — In the Pacific coastal states, Lyme disease is transmitted by the female western black-legged tick (Ixodes pacificus). Most ticks become infected as juveniles when they take a blood meal from an infected wildlife host, most commonly rodents. Ticks must be attached for 24 to 48 hours to transmit disease.
  • Signs — Lyme disease signs are usually non-specific and may include lethargy, enlarged lymph nodes, decreased appetite, fever, stiffness, joint pain or swelling, and shifting limb lameness. In severe cases, Lyme disease can cause kidney inflammation and dysfunction, with signs that include vomiting, weight loss, and increased thirst and urination. Lyme disease can also cause arthritis in several joints throughout the body (i.e., polyarthritis).
  • Diagnosis — Serologic blood assays are used most commonly to diagnose Lyme disease in pets. Other tests, such as a complete blood count, biochemistry profile, urinalysis, and X-rays, may also be necessary.
  • Treatment — Lyme disease usually responds to a particular antibiotic class. Treatment typically takes at least four weeks, and signs sometimes return when medication is stopped. Supportive care may be necessary in severe cases.
  • Vaccination — A Lyme vaccine is available for dogs, and our Fremont Animal Hospital team can evaluate your dog’s lifestyle and disease risk and decide if they are a good candidate.

Anaplasmosis in pets

Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum. According to the Companion Animal Parasite Council (CAPC), incidence is spreading westward. Relevant anaplasmosis information includes:

  • Transmission — In the Pacific coastal states, anaplasmosis is transmitted by the western black-legged tick, which is also a vector for other diseases. Therefore, many anaplasma-positive pets have co-infections with other tick-borne diseases, such as ehrlichiosis, Lyme disease, and Rocky Mountain spotted fever. The tick must be attached for 12 to 24 hours to transmit anaplasmosis.
  • Signs — Anaplasma signs are typically vague and non-specific, including lameness and joint pain, lethargy, inappetence, and fever. Less commonly, coughing, vomiting, diarrhea, and seizures occur.
  • Diagnosis — Anaplasmosis in pets is most commonly diagnosed using serologic blood assays. Other diagnostics may also be recommended.
  • Treatment — Anaplasmosis usually responds to a particular antibiotic class. Most pets are treated for 14 to 30 days, but improvement is typically seen a few days after treatment starts.

Tick-borne relapsing fever in pets

Tick-borne relapsing fever (TBRF) is caused by several bacteria species in the Borrelia genus, most commonly Borrelia hermsii. Most TBRF cases occur in rural, mountainous areas in the western United States, and large TBRF outbreaks have been linked to rustic cabins near national parks. Relevant TBRF information includes:

  • Transmission — TBRF is transmitted by the soft tick, Ornithodoros hermsi, which is associated with rodents living in coniferous forests at higher elevations. Soft ticks spend less time attached to their host than other tick species, and can transmit TBRF bacteria in about 30 minutes.
  • Signs — TBRF signs commonly include lethargy, inappetence, and fever. Lameness and neurological signs, such as incoordination, abnormal posture, and cranial nerve deficits, may also occur.
  • Diagnosis — Visualizing TBRF bacteria on standard blood films is considered diagnostic for the disease, and a blood assay is also available.
  • Treatment — TBRF is usually responsive to a particular antibiotic class, and signs typically resolve after a minimum three-week treatment course.

Tick paralysis in pets

Tick paralysis is caused by a neurotoxin produced in the salivary glands of certain female ticks. Relevant information about TBRF includes:

  • Transmission — Tick paralysis is most commonly caused by the Ixodes, Dermacentor, and Amblyomma ticks, which produce a neurotoxin that inhibits neurotransmitters required for muscle movement. 
  • Signs — Signs typically begin about five to nine days after the tick attaches and first include an ascending paralysis that starts in the hindlimbs and progresses over 24 to 48 hours to include all four limbs. The paralysis can include the muscles needed for breathing. 
  • Diagnosis — Tick paralysis is diagnosed based on clinical signs and treatment response.
  • Treatment — Tick removal is the primary tick paralysis treatment. Supportive care is also necessary until the pet fully recovers from the paralysis. 

Preventing tick-borne diseases in pets

Gloved hands part fur to reveal a tick embedded in an animal's skin, under the watchful eye of a veterinarian.

Tick-borne diseases are concerning, but you can take steps to decrease your pet’s risk. Steps include:

  • Providing year-round tick prevention — Ensure your pet receives year-round tick prevention. These products prevent the tick from finishing its blood meal and transmitting disease.
  • Checking your pet — Check your pet daily for ticks, especially after outings. Common tick hiding locations include the ears, groin, under the tail, and between the toes.
  • Removing the tick — Remove a tick that you find on your pet as soon as possible.

If you would like your dog vaccinated for Lyme disease, or your pet is exhibiting signs that may indicate a tick-borne illness, contact our Fremont Animal Hospital team, so we can determine an appropriate treatment plan.