Tick-borne encephalitis history and symptoms

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Ilan Dock, B.S.

Tick-borne encephalitis infections will often present themselves with biphasic clinical manifestations. Following an incubation period of 7 to 14 days, a patient will experience early onset, non-specific flu like symptoms. A patient will then experience a remission period of lessened symptoms or will appear to be completely asymptomatic.^[1] A second phase will occur in which patients will experience an infection of the central nervous system resulting in a number of neurological, clinical manifestations.

• Symptoms associated with tick-borne encephalitis will appear after an average incubation period of 7 to 14 days.
• The infection usually occurs as a biphasic disease, with early onset symptoms, a period lessened symptoms or asymptomatic(remission), and finally a second phase within 20-30% of patients.^[1]

• Fever
• Malaise
• Anorexia
• Muscle aches
• Headache
• Nausea
• Vomiting^[2]

• Lessened non-specific flu like symptoms
• Completely asymptomatic

• Infection of the central nervous system
• Symptoms associated with meningitis including: fever, headache, and a stiff neck
• Encephalitis
• Drowsiness
• Confusion
• Sensory disturbances
• Motor abnormalities such as paralysis
• Meningoencephalitis^[2]

• Although the above list relates to potential symptoms associated with a full course infection, many infected individuals will remain asymptomatic without any signs of symptoms.
• In addition to the the aforementioned list, symptoms may vary in severity, based on the subtype responsible for infection as well as mode of transmission.