What symptoms arise from an encephalitic tick bite and how soon do they appear? - briefly
Fever, headache, fatigue, muscle aches, nausea and occasionally a rash appear within 2‑7 days after the bite; neurological signs such as confusion, stiff neck, altered consciousness or seizures typically develop 5‑10 days post‑exposure.
What symptoms arise from an encephalitic tick bite and how soon do they appear? - in detail
A bite from a tick infected with the tick‑borne encephalitis virus initiates a two‑phase illness.
The incubation period typically lasts 7–14 days, but cases have been recorded as early as four days and as late as four weeks after exposure.
During the first, non‑specific phase, patients commonly experience:
- Sudden fever (often >38.5 °C)
- Generalized fatigue and malaise
- Headache, frequently frontal or occipital
- Muscle aches, especially in the neck and back
- Nausea, occasional vomiting
- Photophobia or mild visual discomfort
These symptoms usually appear within the first week after the bite and persist for 3–5 days.
In roughly 30 % of individuals, the disease progresses to a second, neurological phase. Neurological manifestations emerge after a brief remission or may follow directly from the initial symptoms, typically between days 5 and 10 of the first phase, though they can appear up to two weeks later. Common signs include:
- Stiff neck and meningeal irritation
- High fever continuing or recurring
- Confusion, disorientation, or altered consciousness
- Focal neurological deficits such as weakness or sensory loss
- Ataxia, tremor, or uncoordinated movements
- Seizures, occasionally generalized tonic‑clonic
- Cranial nerve palsies, most frequently facial nerve involvement
- In severe cases, coma or respiratory failure
The neurological phase may last from several days to several weeks. Recovery varies: many patients improve within weeks, while a minority retain long‑term sequelae such as persistent cognitive impairment, gait disturbances, or chronic fatigue. Early diagnosis and supportive care reduce the risk of severe outcomes.