How does a tick-borne disease present in dogs? - briefly
Infected dogs typically exhibit fever, lethargy, reduced appetite, and joint swelling, and may develop anemia, neurological deficits, or bleeding disorders. Skin lesions or a palpable tick attachment site are also common signs.
How does a tick-borne disease present in dogs? - in detail
Tick-borne infections in canines produce a spectrum of clinical signs that may appear abruptly or develop gradually, depending on the pathogen, the stage of infection, and the host’s immune response.
Common canine tick-borne agents include Ehrlichia canis, Anaplasma phagocytophilum, Borrelia burgdorferi, Babesia canis, Rickettsia rickettsii, and Hepatozoon americanum. Each organism targets specific tissues, yet many share overlapping manifestations.
General systemic signs
- Fever
- Lethargy
- Anorexia
- Weight loss
- Depression
Hematologic abnormalities
- Anemia (normocytic, normochromic)
- Thrombocytopenia, leading to petechiae or ecchymoses
- Leukopenia or leukocytosis with left shift
- Elevated serum globulins
Dermatologic presentations
- Pale mucous membranes (anemia)
- Petechial hemorrhages on skin or mucosa
- Erythematous rash or crusted lesions (particularly with Rickettsia)
- Alopecia secondary to scratching or secondary infection
Musculoskeletal involvement
- Polyarthritis or joint effusion, causing lameness
- Myalgia, evident as stiffness after activity
Neurologic signs
- Ataxia
- Cranial nerve deficits (e.g., facial paresis)
- Seizures (rare, associated with severe Babesia or Ehrlichia infection)
Renal and urinary signs
- Polyuria and polydipsia
- Proteinuria, especially in chronic Ehrlichia infection
- Acute renal failure in severe Babesia cases
Gastrointestinal symptoms
- Vomiting
- Diarrhea, occasionally hemorrhagic
Ocular findings
- Conjunctival hemorrhage
- Uveitis, presenting with photophobia and tearing
Laboratory evaluation often reveals the hematologic changes listed above. Serologic testing (ELISA, indirect immunofluorescence) identifies exposure, while polymerase chain reaction (PCR) confirms active infection. Microscopic examination of blood smears may detect intra‑erythrocytic parasites in Babesia infections.
Acute disease typically presents with fever, lethargy, and abrupt onset of hemorrhagic signs, whereas chronic infection may manifest as intermittent fever, progressive weight loss, and persistent joint swelling. Early detection and targeted antimicrobial therapy (e.g., doxycycline for Ehrlichia and Anaplasma, imidocarb for Babesia) improve prognosis; delayed treatment often leads to irreversible organ damage.
Recognizing the full range of signs enables prompt diagnosis, appropriate laboratory confirmation, and timely intervention, thereby reducing morbidity and mortality associated with tick-transmitted diseases in dogs.