When does a dog feel unwell after a tick bite? - briefly
Illness may develop within 24–48 hours of the bite, showing as fever, lethargy, or loss of appetite. More serious tick‑borne diseases often become apparent 1–3 weeks after exposure.
When does a dog feel unwell after a tick bite? - in detail
A dog may exhibit signs of illness within minutes to several weeks after a tick attaches. Immediate reactions often involve localized swelling, redness, or pain at the bite site. These symptoms arise from the mechanical injury and the salivary proteins injected during feeding.
Systemic manifestations develop according to the pathogen transmitted:
- Within 24–48 hours: Acute fever, lethargy, loss of appetite, and mild joint pain can appear if the tick carries bacteria such as Anaplasma or Ehrlichia. Some dogs also develop a transient rash or bruising.
- 3–7 days: Progression to higher fever, pronounced lethargy, vomiting, diarrhea, and noticeable joint swelling is common with early-stage ehrlichiosis or anaplasmosis. Laboratory tests may reveal low platelet counts or elevated liver enzymes.
- 2–4 weeks: Lyme disease, caused by Borrelia burgdorferi, typically presents with intermittent lameness, joint swelling, and occasional fever. Neurological signs, such as facial nerve paralysis, may emerge later.
- 4–6 weeks or longer: Rocky Mountain spotted fever or other rickettsial infections can cause delayed fever spikes, severe lethargy, and hemorrhagic signs, especially in immunocompromised animals.
If any of these signs appear after a known tick exposure, prompt veterinary evaluation is essential. Early diagnosis, often confirmed by serology or PCR, allows timely antimicrobial therapy and supportive care, reducing the risk of chronic complications.