How long after a tick bite do symptoms of tick-borne encephalitis appear? - briefly
Symptoms usually emerge 7–14 days after the bite, though onset can range from 3 days to about 30 days. Early signs include fever, headache, and malaise, followed by possible neurological manifestations.
How long after a tick bite do symptoms of tick-borne encephalitis appear? - in detail
The interval between a tick attachment and the first clinical signs of tick‑borne encephalitis (TBE) typically ranges from 7 to 14 days, although extremes of 4 to 28 days are documented. This period is called the incubation phase and reflects viral replication at the bite site before systemic spread.
During the incubation phase the patient is asymptomatic. Once the virus reaches the bloodstream, the prodromal phase appears, lasting 1‑3 days and characterized by:
- Low‑grade fever
- Headache
- Malaise
- Muscle aches
- Nausea or vomiting
In roughly 30 % of cases, the illness progresses to the neurologic phase after a brief remission of 1‑5 days. Neurologic manifestations emerge 5‑10 days after the prodrome and include:
- High fever
- Severe headache
- Neck stiffness
- Photophobia
- Confusion or altered consciousness
- Focal neurological deficits (e.g., facial palsy, ataxia)
- Meningitis or encephalitis signs
The timing of each stage is influenced by:
- Viral strain (European vs. Siberian subtypes)
- Tick attachment duration
- Host age and immune status
- Pre‑existing vaccination against TBE
Laboratory confirmation is usually obtained by detecting specific IgM and IgG antibodies in serum or cerebrospinal fluid. Polymerase chain reaction (PCR) is rarely positive after the first week.
Early recognition within the incubation or prodromal window is critical because supportive care and, where indicated, antiviral agents (e.g., ribavirin in experimental settings) are most effective before extensive neuronal injury occurs. Vaccination remains the primary preventive measure, providing durable immunity and shortening or eliminating the symptomatic interval after exposure.