How many days does fever last after a tick bite? - briefly
Fever that develops after a tick bite usually lasts three to seven days, though some cases may continue for up to fourteen days if the underlying infection is more severe. Persistent fever beyond two weeks warrants medical evaluation for potential complications.
How many days does fever last after a tick bite? - in detail
Fever that appears after a tick attachment usually begins within a few days to two weeks, depending on the pathogen transmitted. The most common agents are Borrelia burgdorferi (Lyme disease), Rickettsia rickettsii (Rocky Mountain spotted fever), and various Anaplasma and Ehrlichia species.
In Lyme disease, the fever is often low‑grade and may last 3–7 days if untreated; antibiotics typically shorten the course to 24–48 hours. Rocky Mountain spotted fever produces a higher fever that persists 5–10 days without therapy; doxycycline reduces the duration to 1–3 days. Anaplasmosis and ehrlichiosis generate fevers that resolve in 4–6 days after appropriate antimicrobial treatment, but may continue for up to 10 days if left untreated.
Factors influencing the length of the febrile period include:
- Time elapsed between bite and onset of symptoms
- Specific microorganism and its virulence
- Host immune status and age
- Promptness and adequacy of antimicrobial therapy
If fever lasts longer than a week, escalates in intensity, or is accompanied by rash, severe headache, joint pain, or neurologic signs, medical evaluation is required. Early diagnosis and treatment are essential to prevent complications and to shorten the febrile phase.