What are the signs of encephalitis after a tick bite in a person and when do they appear? - briefly
The condition, known as «encephalitis», presents with fever, severe headache, neck stiffness, and altered mental status, typically emerging 1–3 weeks after a tick bite. Neurological deficits such as seizures, confusion, or focal weakness may develop subsequently, often within days of symptom onset.
What are the signs of encephalitis after a tick bite in a person and when do they appear? - in detail
Encephalitis that follows a tick attachment typically develops within 1 – 4 weeks after the bite, although incubation may be shorter in children and longer in adults. Early neurological manifestations often precede the classic encephalitic picture and include:
- Severe headache, frequently described as “throbbing” or “pressure‑like.”
- Fever exceeding 38 °C, sometimes accompanied by chills.
- Nausea and vomiting without an obvious gastrointestinal cause.
- Photophobia and neck stiffness, indicating meningeal irritation.
As the disease progresses, more specific cerebral involvement becomes evident:
- Altered mental status ranging from confusion and disorientation to stupor or coma.
- Focal neurological deficits such as weakness, paresthesia, or cranial nerve palsies.
- Seizure activity, which may be generalized or focal.
- Behavioral changes, including agitation, irritability, or psychotic features.
- Dysarthria or dysphagia reflecting brain‑stem involvement.
Laboratory and imaging findings support the clinical picture. Cerebrospinal fluid analysis usually shows lymphocytic pleocytosis, elevated protein, and normal or mildly reduced glucose. Magnetic resonance imaging often reveals hyperintense lesions in the basal ganglia, thalami, or cerebral cortex.
Prompt recognition of these signs within the first month after a tick bite is critical for early antiviral or supportive therapy, which can reduce morbidity and improve outcomes.