How long after a bite from an encephalitis tick do symptoms appear and what are they? - briefly
Symptoms usually develop within one to two weeks after the tick bite, though incubation can range from a few days up to three weeks. Early manifestations include fever, headache, fatigue, and nausea, followed by neurological signs such as neck stiffness, photophobia, confusion, seizures, or facial paralysis.
How long after a bite from an encephalitis tick do symptoms appear and what are they? - in detail
The incubation period after a tick bite that transmits tick‑borne encephalitis (TBE) typically ranges from 7 to 14 days, but cases have been reported with intervals up to 28 days. The disease often follows a biphasic course.
In the initial phase, patients experience nonspecific, systemic signs that resemble a viral infection. Common manifestations include:
- Sudden fever (38–40 °C)
- Headache
- Malaise and fatigue
- Myalgia, especially in the neck and shoulder girdle
- Nausea, sometimes accompanied by vomiting
- Retro‑orbital pain
These symptoms usually persist for 2–7 days and may resolve spontaneously, leading to a brief asymptomatic interval before the second phase begins.
The second phase reflects central nervous system involvement and appears after a short remission of 1–5 days. Neurological presentations are diverse:
- High‑grade fever that may recur
- Severe headache, often described as meningitic
- Neck stiffness and photophobia (meningitis)
- Altered consciousness, ranging from confusion to coma
- Focal neurological deficits, such as ataxia, tremor, or paresis
- Cranial nerve palsies, especially facial nerve (VII) involvement
- Seizures, less common but possible
- Long‑lasting sequelae, including cognitive impairment, persistent gait disturbance, or chronic fatigue
The severity of the second phase varies. Approximately 30 % of patients develop a purely meningitic picture, while 10–20 % progress to encephalitis or meningo‑encephalomyelitis, which carries a higher risk of lasting disability or death.
Rapid recognition of the biphasic pattern and early supportive care improve outcomes. Antiviral therapy is not established; treatment focuses on managing fever, maintaining hydration, and monitoring for complications such as increased intracranial pressure.