Tick-Borne Diseases (Lyme, Ehrlichia, Anaplasmosis) in Dogs: Symptoms, Diagnosis & Treatment

Veterinary Disclaimer: This article is for informational purposes only and does not substitute for professional veterinary advice, diagnosis, or treatment. If you suspect your dog has a tick-borne disease, consult a licensed veterinarian immediately.

What Are Tick-Borne Diseases (Lyme, Ehrlichia, Anaplasmosis)?

Tick-borne diseases are a group of serious infectious illnesses transmitted to dogs through the bite of infected ticks. The three most common tick-borne diseases in dogs are Lyme disease (caused by Borrelia burgdorferi), ehrlichiosis (caused by Ehrlichia canis and related species), and anaplasmosis (caused by Anaplasma phagocytophilum or Anaplasma platys). These bacterial infections attack different components of a dog's immune system and can cause symptoms ranging from mild lethargy and fever to life-threatening organ failure if left untreated.

When an infected tick attaches to a dog and feeds, the bacteria living in the tick's gut migrate to its salivary glands and are injected into the dog's bloodstream. In the case of Lyme disease, transmission typically requires 24–48 hours of tick attachment, while Ehrlichia and Anaplasma organisms can be transmitted more quickly — sometimes within just a few hours. Once inside the body, each pathogen targets specific cells. Borrelia burgdorferi migrates through connective tissues and joints. Ehrlichia canis invades white blood cells called monocytes and macrophages. Anaplasma phagocytophilum attacks granulocytes (another type of white blood cell), while Anaplasma platys targets platelets, the cells responsible for blood clotting.

Dogs can be infected with more than one tick-borne pathogen simultaneously — a condition known as co-infection — which can complicate diagnosis and worsen outcomes. Tick-borne diseases are found throughout the United States and worldwide, with geographic prevalence varying by tick species and local ecology.

Symptoms of Tick-Borne Diseases (Lyme, Ehrlichia, Anaplasmosis) in Dogs

Symptoms can vary widely depending on which pathogen is involved, the stage of infection, and the individual dog's immune response. Many dogs remain asymptomatic for weeks or even months after initial infection.

Early Signs

These are often subtle and easily mistaken for general malaise:

• Fever (typically 103–105°F / 39.4–40.6°C)
• Lethargy and decreased energy — your dog may seem "off" or unusually tired
• Loss of appetite (anorexia or reduced food intake)
• Swollen lymph nodes (lymphadenopathy), often noticed around the neck or behind the knees
• Shifting-leg lameness (especially with Lyme disease) — limping that moves from one leg to another
• Joint swelling or stiffness, particularly in larger joints
• Mild weight loss

Progressive Symptoms

As the disease advances or enters a chronic phase, more significant signs develop:

• Persistent or recurring lameness (Lyme disease)
• Muscle pain and generalized stiffness
• Nosebleeds (epistaxis) — particularly common with ehrlichiosis and anaplasmosis due to low platelet counts
• Bruising or petechiae (tiny red spots on skin, gums, or inner ear flaps)
• Pale gums indicating anemia
• Eye inflammation (uveitis), cloudy eyes, or excessive tearing
• Vomiting and diarrhea
• Swollen, painful joints (polyarthritis)
• Peripheral edema — swelling in the legs or face
• Chronic weight loss and muscle wasting
• Splenomegaly (enlarged spleen)

Emergency Signs

Seek immediate veterinary care if you observe:

• Difficulty breathing or rapid breathing (dyspnea/tachypnea)
• Collapse or severe weakness
• Uncontrolled bleeding from the nose, gums, or in urine/stool
• Severe swelling of limbs or face
• Seizures or neurological symptoms (disorientation, head tilt, ataxia)
• Dark or bloody urine — may indicate kidney involvement (Lyme nephritis) or severe hemolysis
• Extremely pale or yellow-tinged gums (jaundice/icterus)
• High fever above 105°F (40.6°C) that is unresponsive to treatment

What Causes Tick-Borne Diseases (Lyme, Ehrlichia, Anaplasmosis) in Dogs?

The Vectors

Each disease is transmitted by specific tick species:

• Lyme disease: Transmitted primarily by the black-legged tick (Ixodes scapularis) in the eastern U.S. and the western black-legged tick (Ixodes pacificus) on the Pacific coast. Deer ticks require 24–48 hours of attachment to transmit Borrelia burgdorferi.
• Ehrlichiosis: Transmitted mainly by the brown dog tick (Rhipicephalus sanguineus) and the lone star tick (Amblyomma americanum). The brown dog tick is unique in that it can complete its entire life cycle indoors.
• Anaplasmosis: A. phagocytophilum is transmitted by the same black-legged ticks that carry Lyme disease. A. platys is spread by the brown dog tick.

Risk Factors

• Geographic location: Lyme disease is most prevalent in the Northeast, upper Midwest, and Pacific coast. Ehrlichiosis is common in the southeastern and south-central U.S. Anaplasmosis occurs broadly wherever its tick vectors are found.
• Outdoor exposure: Dogs that spend significant time in wooded areas, tall grass, brush, or areas with heavy deer and rodent populations face elevated risk.
• Season: Peak tick activity occurs in spring and fall, though in warmer climates ticks are active year-round.
• Lack of tick prevention: Dogs not on regular tick-preventive medications are at significantly higher risk.
• Age: While any dog can be infected, very young puppies and senior dogs with weaker immune systems may develop more severe illness.
• Immune status: Dogs that are immunocompromised — due to concurrent illness, stress, or medications like corticosteroids — may be more susceptible to severe disease.
• Co-infection: Dogs exposed to ticks carrying multiple pathogens can develop simultaneous infections, leading to more complex and severe disease presentations.

Breeds Most at Risk

Tick-borne diseases can affect any dog regardless of breed, size, or age. However, certain breeds show heightened susceptibility to severe complications:

• Labrador Retrievers and Golden Retrievers: These breeds are significantly overrepresented in cases of Lyme nephritis, a potentially fatal kidney complication. A genetic predisposition is strongly suspected, possibly related to how their immune system responds to Borrelia antigens.
• Shetland Sheepdogs: Have shown increased susceptibility to Lyme nephritis.
• Bernese Mountain Dogs: Appear to be at elevated risk for severe Lyme disease complications, including glomerulonephritis.
• German Shepherds: Have been reported to be more susceptible to severe chronic ehrlichiosis, which may be related to breed-associated immune response patterns.
• Doberman Pinschers and Greyhounds: Some studies suggest a tendency toward more severe manifestations of ehrlichiosis.
• Sporting and working breeds: Breeds commonly used for hunting, herding, or other outdoor work (e.g., Beagles, Pointers, Border Collies, Australian Shepherds) face higher exposure risk simply due to lifestyle and time spent in tick-heavy environments.

How Tick-Borne Diseases (Lyme, Ehrlichia, Anaplasmosis) Are Diagnosed

Diagnosis often involves a combination of clinical signs, history of tick exposure, and laboratory testing. Many dogs test positive on screening but remain asymptomatic, so veterinarians must interpret results in context.

Step 1: Physical Examination and History

Your veterinarian will perform a thorough physical exam looking for fever, joint swelling, lymph node enlargement, and signs of bleeding. They will ask about tick exposure history, geographic location, travel history, and tick-prevention protocols. Typical cost: $50–$75 (exam fee).

Step 2: SNAP 4Dx or Similar In-Clinic Test

The IDEXX SNAP 4Dx Plus test is the most commonly used screening tool. It detects antibodies to Borrelia burgdorferi, Ehrlichia canis, Ehrlichia ewingii, Anaplasma phagocytophilum, Anaplasma platys, and also screens for heartworm. Results are available in about 8 minutes. A positive result indicates exposure but does not necessarily mean active infection. Typical cost: $45–$80.

Step 3: Complete Blood Count (CBC) and Chemistry Panel

Blood work reveals critical information:

• Low platelet count (thrombocytopenia): Very common with ehrlichiosis and anaplasmosis
• Anemia: Seen in chronic ehrlichiosis and sometimes anaplasmosis
• Low white blood cell count (leukopenia) or elevated white cells depending on disease stage
• Elevated liver or kidney values: Indicate organ involvement
• High protein levels (hyperglobulinemia): Common in chronic ehrlichiosis

Step 4: Urinalysis

Especially important for suspected Lyme disease to check for protein loss in urine (proteinuria), which can signal Lyme nephritis. A urine protein-to-creatinine ratio (UPC) quantifies the severity. Typical cost: $30–$75.

Step 5: Advanced Testing (When Indicated)

• Quantitative C6 antibody test (Lyme Quant C6): Measures the level of Lyme-specific antibodies; useful for monitoring treatment response. Cost: $150–$300.
• PCR (Polymerase Chain Reaction): Detects actual pathogen DNA in blood or joint fluid. Highly specific but can yield false negatives if bacterial load is low. Cost: $150–$350.
• Antibody titers: Serial measurements can help determine if infection is active versus historical exposure.
• Joint fluid analysis (arthrocentesis): May be performed if joint disease is prominent, to rule out other causes of polyarthritis. Cost: $200–$400.

Treatment Options for Tick-Borne Diseases (Lyme, Ehrlichia, Anaplasmosis)

Medical Management

Antibiotic therapy is the cornerstone of treatment for all three diseases:

• Doxycycline is the first-line antibiotic for Lyme disease, ehrlichiosis, and anaplasmosis. The standard protocol is 5 mg/kg orally twice daily (or 10 mg/kg once daily) for 28–30 days. Doxycycline is effective against all three pathogens, making it particularly useful when co-infection is suspected.
• Minocycline may be used as an alternative if doxycycline is not tolerated.
• Chloramphenicol is sometimes used for anaplasmosis in very young puppies where doxycycline may affect developing teeth, though this is uncommon.
• Imidocarb dipropionate may be used for refractory ehrlichiosis cases, administered by injection.

• Non-steroidal anti-inflammatory drugs (NSAIDs) such as carprofen or meloxicam for pain and joint inflammation
• Gastroprotectants (omeprazole, sucralfate) to protect the stomach during antibiotic therapy
• Immunosuppressive therapy (prednisone or other corticosteroids) in cases of immune-mediated complications such as severe thrombocytopenia or polyarthritis unresponsive to antibiotics alone

• IV fluid therapy for rehydration and kidney support
• ACE inhibitors (e.g., enalapril) to reduce proteinuria
• Anti-hypertensive medications
• Low-dose aspirin to reduce glomerular inflammation
• Dietary protein management

Surgical Options

Tick-borne diseases are managed medically rather than surgically. However, surgical intervention may be needed in rare scenarios such as drainage of severely affected joints or splenectomy in cases of splenic complications.

Alternative/Supportive Therapies

• Omega-3 fatty acid supplementation: May help reduce joint inflammation and support kidney function
• Probiotics: Help maintain gut health during prolonged antibiotic therapy
• Joint supplements: Glucosamine and chondroitin may support joint recovery in dogs with Lyme arthritis
• Acupuncture: Some veterinary practitioners use acupuncture to help manage chronic pain from tick-borne arthritis
• Physical rehabilitation: Hydrotherapy and controlled exercise can aid recovery from joint disease and muscle wasting

At-Home Care

• Complete the full antibiotic course — stopping early risks relapse and resistance
• Administer doxycycline with a small amount of food to reduce gastrointestinal upset; avoid dairy products within 2 hours of dosing as calcium can reduce absorption
• Monitor for side effects: Watch for vomiting, diarrhea, or loss of appetite during treatment
• Restrict activity during the acute phase, especially if your dog has joint pain or lameness
• Ensure adequate hydration — keep fresh water available at all times
• Follow up with your veterinarian for recommended recheck appointments and repeat blood work
• Begin or continue tick prevention immediately to prevent reinfection

Prognosis & Life Expectancy

The prognosis for tick-borne diseases varies significantly based on the specific pathogen, how early treatment begins, and the presence of complications.

Dogs that recover from tick-borne diseases can live normal, full lifespans. Antibody levels may remain elevated for months to years after successful treatment, which does not necessarily indicate ongoing infection.

Prevention

Prevention is far more effective than treatment and should be a priority for all dog owners, especially in tick-endemic regions.

Tick Prevention Products

• Oral preventives: Isoxazoline-class medications (fluralaner/Bravecto, afoxolaner/NexGard, sarolaner/Simparica, lotilaner/Credelio) are highly effective and kill ticks within hours of attachment — often before disease transmission can occur. These are available by prescription.
• Topical preventives: Products containing fipronil, permethrin (dogs only — toxic to cats), or selamectin provide effective tick control.
• Tick collars: Seresto collars release imidacloprid and flumethrin over 8 months and provide reliable tick repellency and kill.
• Year-round prevention is recommended, even in colder climates, as ticks can be active on warmer winter days.

Vaccination

A Lyme disease vaccine is available for dogs and may be recommended in high-risk areas. The vaccine targets the OspA protein of Borrelia burgdorferi and can reduce the risk of infection. Discuss the benefits and risks with your veterinarian, as the vaccine is not universally recommended. No vaccines currently exist for ehrlichiosis or anaplasmosis.

Environmental Management

• Keep grass mowed short and clear brush from yards
• Create gravel or wood chip barriers between wooded areas and lawns
• Remove leaf litter and debris where ticks harbor
• Discourage deer and rodents (primary tick hosts) from frequenting your property
• Perform daily tick checks on your dog after outdoor activity — especially around the ears, between toes, in the groin, and under the collar

Screening

• Annual SNAP 4Dx testing is recommended for all dogs as part of routine wellness care, regardless of whether symptoms are present
• Early detection of subclinical infection allows for monitoring and timely intervention

Breeding Considerations

There are no direct hereditary tick-borne disease concerns, but given the documented breed predisposition for Lyme nephritis in Labrador Retrievers, Golden Retrievers, and Bernese Mountain Dogs, owners and breeders of these breeds should be especially vigilant about tick prevention and regular screening.

Cost of Treatment

Treatment costs vary based on disease severity, geographic location, and whether complications develop.

| Component | Estimated Cost Range | |---|---| | Initial examination | $50–$75 | | SNAP 4Dx screening test | $45–$80 | | CBC and chemistry panel | $125–$250 | | Urinalysis with UPC ratio | $30–$75 | | Quantitative C6 test (Lyme) | $150–$300 | | PCR testing | $150–$350 | | Doxycycline (30-day course) | $30–$100 | | NSAIDs (monthly) | $25–$60 | | Follow-up blood work | $100–$200 | | Uncomplicated total | $400–$900 | | Complicated cases (hospitalization, Lyme nephritis) | $2,000–$10,000+ |

Monthly tick prevention products typically cost $15–$50 depending on the product and dog's size — a fraction of the cost of treating an active infection.

Frequently Asked Questions

Can humans catch tick-borne diseases from their dogs?

Humans cannot contract tick-borne diseases directly from an infected dog. However, the same ticks that infect dogs can also bite and infect humans. If your dog is diagnosed with a tick-borne illness, it means infected ticks are present in your environment, and you should take personal protective measures and consult your physician.

My dog tested positive on a SNAP test but seems perfectly healthy. Does he need treatment?

This is a common scenario. A positive test indicates exposure and antibody production, not necessarily active disease. Your veterinarian will likely recommend additional testing (CBC, urinalysis, Lyme Quant C6) to determine if treatment is warranted. Many veterinarians adopt a "monitor and treat if symptomatic" approach for seropositive-but-healthy dogs, while others prefer to treat proactively — especially for Lyme disease given the risk of nephritis.

How long after a tick bite does it take for symptoms to appear?

The incubation period varies by disease. Lyme disease symptoms typically appear 2–5 months after the tick bite. Ehrlichiosis has a shorter incubation of 1–3 weeks. Anaplasmosis symptoms usually develop within 1–2 weeks of the tick bite. Some dogs remain asymptomatic for months or years before clinical signs emerge.

Can my dog get the same tick-borne disease twice?

Yes. Infection with one tick-borne pathogen does not provide lifelong immunity. Dogs can be reinfected with the same organism, and they can also be infected with multiple tick-borne pathogens simultaneously. This is why continuous tick prevention is essential.

Are tick-borne diseases curable?

In most cases, yes — especially when caught early. Doxycycline is highly effective, and most dogs recover fully with a standard 28–30 day course. However, some dogs (particularly with chronic ehrlichiosis or Lyme nephritis) may not achieve complete clearance, and antibody titers can remain elevated long after treatment. A persistent positive test does not always mean the dog is still infected.

Is the Lyme vaccine worth it for my dog?

The Lyme vaccine can be beneficial for dogs living in or traveling to high-risk areas where Lyme disease is prevalent. It is generally safe, though no vaccine is 100% effective. The vaccine should be used in addition to — not instead of — tick prevention products. Discuss your dog's specific risk profile with your veterinarian to make an informed decision.

How do I properly remove a tick from my dog?

Use fine-tipped tweezers or a tick-removal tool. Grasp the tick as close to your dog's skin as possible and pull upward with steady, even pressure. Do not twist, jerk, or squeeze the tick's body, as this can cause the mouthparts to break off or push infected material into the wound. After removal, clean the bite area with antiseptic and save the tick in a sealed container in case your veterinarian wants to identify the species. Monitor the bite site for signs of infection over the following days.

Should I be worried about my other pets if one dog tests positive?

A positive test in one dog means infected ticks are in your environment. All pets — dogs and cats — should be on appropriate tick prevention. Have all dogs in the household tested. Cats can also be affected by certain tick-borne organisms, though clinical disease is less common. There is no direct dog-to-dog transmission of these diseases; the tick vector is always required.

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This article was reviewed for medical accuracy and is intended as an educational resource for dog owners. Always work with your veterinarian to develop the best diagnostic and treatment plan for your individual pet.