Why is an encephalitis tick dangerous? - briefly
The tick transmits tick‑borne encephalitis virus, which can inflame the brain and result in seizures, paralysis, or death. Initial symptoms resemble a mild flu, complicating early detection.
Why is an encephalitis tick dangerous? - in detail
The tick that transmits tick‑borne encephalitis (TBE) carries a flavivirus capable of invading the central nervous system. Once attached, the arthropod can inoculate the virus during a blood meal, often within 24–48 hours of attachment. This short window leaves little opportunity for removal before infection occurs.
The virus replicates initially in skin cells and regional lymph nodes, then spreads hematogenously to the brain. Early symptoms—fever, headache, fatigue—may be mistaken for a mild viral illness, delaying diagnosis. Within days, neurological signs emerge: meningitis, encephalitis, or meningoencephalitis, characterized by stiff neck, confusion, seizures, and possible paralysis. Permanent cognitive deficits, motor dysfunction, or hearing loss develop in a significant proportion of survivors. Mortality rates range from 1 % to 20 % depending on viral strain and patient age, with higher risk in older adults and immunocompromised individuals.
Key factors that increase the threat:
- Geographic distribution – endemic in forested regions of Europe and Asia where human exposure is common.
- Tick activity period – peak questing activity from spring to autumn aligns with outdoor recreation.
- Host range – larvae and nymphs feed on small mammals that maintain the virus, facilitating transmission to humans.
- Absence of universal vaccine – vaccination is available only in certain countries; many at‑risk populations remain unprotected.
- Limited antiviral therapy – treatment is supportive; no specific antivirals are approved for TBE.
Preventive measures focus on reducing tick bites: wearing protective clothing, applying repellents containing DEET or permethrin, performing thorough body checks after outdoor exposure, and promptly removing attached ticks with fine‑pointed tweezers. In regions where immunization programs exist, vaccination provides the most effective reduction in disease incidence.