What are the symptoms of a tick‑borne encephalitis bite? - briefly
Fever, severe headache, neck stiffness, nausea or vomiting, confusion, seizures, and possible focal neurological deficits such as weakness or paralysis may appear within 1‑3 weeks after a tick bite transmitting the virus.
What are the symptoms of a tick‑borne encephalitis bite? - in detail
Tick‑borne encephalitis (TBE) presents after a bite from an infected Ixodes tick. The disease typically follows a biphasic course, although some patients experience a single, continuous phase.
First (prodromal) phase – lasts 1–7 days
- Sudden fever, often 38‑40 °C
- Headache, sometimes described as frontal or occipital
- Muscle aches (myalgia) and joint pain (arthralgia)
- General weakness and fatigue
- Nausea, vomiting, or loss of appetite
- Occasionally, a mild sore throat or conjunctival injection
During this stage, laboratory tests may reveal leukopenia, thrombocytopenia, or mildly elevated liver enzymes, but these findings are not specific.
Second (neurological) phase – begins after a brief asymptomatic interval of 2–10 days, lasting from several days up to weeks
- High fever persisting or recurring
- Neck stiffness and photophobia, indicating meningeal irritation
- Severe headache, often localized to the occipital region
- Altered mental status: confusion, irritability, or somnolence
- Focal neurological deficits:
- Cranial nerve palsies (e.g., facial weakness)
- Limb paresis or ataxia, reflecting cerebellar involvement
- Dysarthria or dysphagia if brainstem is affected
- Seizures, more common in children and severe adult cases
- Sensory disturbances: tingling, numbness, or paresthesia in extremities
- Persistent vomiting and, in some cases, urinary retention
Rare complications
- Encephalomyelitis with combined brain and spinal cord inflammation
- Long‑term sequelae such as chronic paresis, cognitive impairment, or vestibular dysfunction lasting months to years
The severity of neurological symptoms varies with viral subtype, patient age, and immune status. Prompt recognition of the biphasic pattern and early supportive care are essential to reduce morbidity. Diagnostic confirmation relies on serology (IgM/IgG antibodies) and, when necessary, PCR detection of viral RNA in cerebrospinal fluid.