What is Tick-Borne Encephalitis?
what-is-tbe
What is Tick-Borne Encephalitis?
Know the Facts to Help Protect Yourself from TBE
It Can Take Just One Bite
Tick-borne encephalitis (TBE) is a rare viral infection of the brain and spine.1 Transmission of the TBE virus to humans most commonly occurs from the bite of an infected tick.2 Encephalitis means inflammation of the brain.3
What You Should Know
Know Facts #1

#1

Ticks infected with the
TBE virus are not confined to one country, with
reports of infected ticks in over
30 countries across Europe
to Asia.2,4

Know facts #2

#2

Ticks are typically active from April through November.4 However, tick season can vary each year depending on the climate.1,5

Know facts #3

#3

There is no cure for TBE, and it cannot be treated with antibiotics or any other medication.2,6

Know facts #4

#4

Depending on the sub-type of virus, 10-50% of people may experience neurological symptoms.7

Complications from TBE include:
Help Protect Yourself!
Signs & Symptoms
Most people infected with the TBE virus have no symptoms.4 But if symptoms occur, they usually appear in two phases.4 In the initial phase, people may experience symptoms including fever, headache, vomiting, and weakness.9 Some people experience the second phase, which can be serious with symptoms that may include confusion, loss of coordination, difficulty speaking, weakness of the arms or legs, and seizures.9
Common symptoms across phases10:
Headache
Headache
fatigue
Fatigue
Muscule-pain
Muscle Pain
High-fever
High Fever 
(around 102oF)
Nausae
Nausea
Vomiting
Vomiting
vertigo
Vertigo
References
  1. Lindquist L, Vapalahti O. Tick-borne encephalitis. Lancet. 2008;371(9627):1861-1871. doi:10.1016/S0140-6736(08)60800-4
  2. Dobler G, Erber W, Bröker M, Schmitt HJ, eds. The TBE Book. 4th ed. Global Health Press; 2021.
  3. Mayo Clinic. Diseases & Conditions. Encephalitis. Accessed August 20, 2025. https://www.mayoclinic.org/diseases-conditions/.
  4. Susan L. Hills and Carolyn V. Gould. Tickborne Encephalitis. Centers for Disease Control and Prevention. CDC Yellow Book: Health Information for International Travel. Accessed August 20, 2025. https://www.cdc.gov/yellow-book/hcp/travel-associated-infections-diseases/tick-borne-encephalitis.html.
  5. Bogovic P, Strle F. Tick-borne encephalitis: A review of epidemiology, clinical characteristics, and management. World J Clin Cases. 2015;3(5):430-441. doi:10.12998/wjcc.v3.i5.430.
  6. TicoVac (Tick-Borne Encephalitis Vaccine). Prescribing Information. New York, NY: Pfizer Inc. 2023.
  7. Centers for Disease Control and Prevention. Clinical Signs and Symptoms of Tick-borne Encephalitis. Accessed August 20, 2025. https://www.cdc.gov/tick-borne-encephalitis/hcp/clinical-signs.
  8. Haglund M, Günther G. Tick-borne encephalitis—pathogenesis, clinical course and long-term follow-up. Vaccine. 2003;21(suppl 1):S11-18. doi:10.1016/s0264-410x(02)00811-3.
  9. Centers for Disease Control and Prevention. Tick-borne encephalitis (TBE): Symptoms, Diagnosis, and Treatment. Accessed August 20, 2025. https://www.cdc.gov/tick-borne-encephalitis/symptoms-diagnosis-treatment/index.html.
  10. Kaiser R. Tick-borne encephalitis. Infect Dis Clin North Am. 2008;22(3):561-575. doi:10.1016/j.idc.2008.03.013.

IMPORTANT SAFETY INFORMATION AND INDICATION

Important Safety Information
  • TicoVac® should not be given to anyone with a history of a severe allergic reaction after a previous dose of TicoVac.
  • TicoVac may not protect all individuals against TBE.
  • Some individuals with weakened immune systems may have a reduced immune response.
  • TicoVac contains albumin, a derivative of human blood. Based on effective donor screening and product manufacturing processes, it carries an extremely remote risk for transmission of viral diseases.
  • The most common adverse reactions in subjects 1 through 15 years of age who received TicoVac were local tenderness, local pain, headache, fever, and restlessness.
  • The most common adverse reactions in subjects 16 through 65 years of age who received TicoVac were local tenderness, local pain, fatigue, headache, and muscle pain.
  • Tell your healthcare provider if you are pregnant, or plan to become pregnant.
  • Ask your healthcare provider about the risks and benefits for TicoVac. Only a healthcare provider can decide if TicoVac is right for you.
Indication
  • TicoVac is a vaccine indicated for active immunization to prevent tick-borne encephalitis (TBE) and is approved for use in individuals 1 year of age and older.

You are encouraged to report negative side effects of vaccines to the US Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC). Visit http://www.vaers.hhs.gov or call 1-800-822-7967.

Please see full prescribing information for TicoVac here.

IMPORTANT SAFETY INFORMATION AND INDICATION

Important Safety Information
  • TicoVac® should not be given to anyone with a history of a severe allergic reaction after a previous dose of TicoVac.
  • TicoVac may not protect all individuals against TBE.
  • Some individuals with weakened immune systems may have a reduced immune response.
  • TicoVac contains albumin, a derivative of human blood. Based on effective donor screening and product manufacturing processes, it carries an extremely remote risk for transmission of viral diseases.
  • The most common adverse reactions in subjects 1 through 15 years of age who received TicoVac were local tenderness, local pain, headache, fever, and restlessness.
  • The most common adverse reactions in subjects 16 through 65 years of age who received TicoVac were local tenderness, local pain, fatigue, headache, and muscle pain.
  • Tell your healthcare provider if you are pregnant, or plan to become pregnant.
  • Ask your healthcare provider about the risks and benefits for TicoVac. Only a healthcare provider can decide if TicoVac is right for you.
Indication
  • TicoVac is a vaccine indicated for active immunization to prevent tick-borne encephalitis (TBE) and is approved for use in individuals 1 year of age and older.

You are encouraged to report negative side effects of vaccines to the US Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC). Visit http://www.vaers.hhs.gov or call 1-800-822-7967.

Please see full prescribing information for TicoVac here.

This site is intended only for U.S. residents. The products discussed in this site may have different product labeling in different countries.
The information provided is for educational purposes only and is not intended to replace discussions with a healthcare provider.
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  • November 2025
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