Ticks are loathsome pests—from the tiny nymph stage to the larger adult stage—that can transmit serious diseases to you and your pet and you. While antibiotic therapy can typically resolve pets’ clinical signs, tick-borne diseases can cause lifelong adverse health conditions and chronic illness, making tick prevention especially important. In addition, diagnosing tick-borne diseases can be difficult, because standard tests detect infection through the presence of antibodies, which develop weeks after a tick bite. 

Tick-borne diseases are serious, and our Wales Animal Clinic team describes Wisconsin’s four most common tick-borne diseases, and disease signs you may see in your pet. 

#1: Lyme disease in pets

Every state has reported Lyme disease—the most notorious tick-borne illness—that continues to spread from its Pennsylvania roots. The deer tick (i.e., black-legged tick) transmits the Lyme bacterium about 48 hours after initially attaching to your pet, so prompt tick removal is important to prevent disease.

Your pet’s Lyme disease signs can vary. Many pets show no signs, but can display:

  • Shifting leg lameness
  • Painful and swollen joints
  • Fever
  • Decreased appetite
  • Lethargy
  • Swollen lymph nodes

In some cases, the Lyme bacterium affects your pet’s kidneys, leading to chronic kidney failure. In rare cases, Lyme bacterium may affect your pet’s heart and nervous system. Antibiotic therapy can help reduce your pet’s infection, although completely eradicating the infection can be difficult. Some affected pets will experience lifelong, chronic joint pain and illness flare-ups.

#2: Ehrlichiosis in pets

The brown dog tick, lone star tick, and black-legged tick transmit Ehrlichia—a bacteria that often targets white blood cells. While various Ehrlichia strains can affect your pet, the disease has two forms—monocytic and granulocytic. Typically, the monocytic form is much more severe, while the granulocytic form may lead to only mild illness, such as fever or swollen joints, or no signs.

Pets who have the more severe monocytic ehrlichiosis may show:

  • Fever
  • Swollen lymph nodes
  • Decreased appetite
  • Depression
  • Lameness
  • Vomiting 
  • Diarrhea
  • Coughing
  • Abnormal bleeding  
  • Abnormal bruising
  • Neurologic abnormalities

The Ehrlichia monocytic form can have acute, subclinical, and chronic phases. Pets experience minimal illness during the subclinical phase, whereas during the chronic phase, they can experience the acute phase’s signs, but more severe. During the acute and subclinical phases, pets have the best prognosis, while the chronic phase can be fatal.

#3: Anaplasmosis in pets

The brown dog tick and black-legged tick transmit bacterial strains that cause anaplasmosis, which is also often seen with other tick-borne illnesses, such as Lyme disease, causing a coinfection with many similar signs.

Infection with the more common anaplasmosis form often causes signs similar to Lyme disease and other tick-borne diseases. These signs include: 

  • Lameness 
  • Joint pain 
  • Fever 
  • Lethargy 
  • Anorexia 

Infected cats’ signs may also include: 

  • Vomiting 
  • Diarrhea 
  • Coughing 
  • Labored breathing

Pets can also experience another anaplasmosis form, which can cause cyclic thrombocytopenia (i.e., a periodic platelet-level decrease) that causes clotting problems, and abnormal bruising or bleeding. 

#4: Rocky Mountain spotted fever in pets

The American dog tick and the wood tick commonly transmit Rocky Mountain spotted fever (RMSF). 

Pets who have RMSF can have vague, nonspecific signs that make diagnosis difficult without tick bite confirmation. However, a pet who has RMSF may show:

  • Inappetence
  • Joint pain
  • Depression
  • Fever
  • Coughing
  • Vomiting
  • Diarrhea
  • Edema in the face and legs
  • Neurological issues (e.g., dizziness, stupor, seizures)

Many pets with RMSF also develop hemorrhages in the eyes and gums, have bloody stool, or experience nosebleeds. Some pets develop pneumonia or heart arrhythmias, which can lead to sudden death. RMSF kills between 1% and 10% of dogs who develop the disease.

Tick-borne diseases can cause your pet serious, potentially chronic, illness. You should take every measure to prevent these parasites from making a meal of your pet, but if you need to pull an attached tick from your pet, first contact our Wales Animal Clinic team for advice. To ensure your pet remains safe from tick-borne illnesses, stop by the clinic and stock up on your furry pal’s tick prevention medicine.