Tick-borne Encephalitis is a viral infection caused by one of three tick-borne encephalitis virus (TBEV) subtypes belonging to the Flaviviridae family: Central European, Siberian, and Far Eastern (formerly known as Russian Spring-Summer Encephalitis). It is transmitted to humans through the bite of infected Ixodes ticks. Due to climate change, tick populations are moving further north in latitude.
Tick-borne Encephalitis occurs in parts of Europe, Central Asia, and East Asia. Travellers involved in outdoor activities in forested areas are at risk, including campers, hikers, and hunters. Brushing against vegetation or walking in city parks known to have infected ticks can also put a person at risk. Transmission season is typically from March to November.
Usually symptoms appear 7 to 14 days after being bitten by an infected tick. Symptoms can last up to 8 days and include fever, headache, fatigue, muscle pain, nausea, and loss of appetite. Approximately one-third of patients develop severe symptoms after the first phase of the illness where the virus causes meningitis (attacks the thin lining that surrounds the brain and the spinal cord) and / or encephalitis (swelling of the brain). Second phase symptoms include stiff neck, fever, headache, nausea, sensitivity to light, confusion, disorientation, drowsiness, behavioural changes, seizures, and paralysis. Some patients may experience long-term complications such as memory loss, speech and language problems, mood disorders, epilepsy, fatigue, and motor skill difficulties. Treatment of the acute infection includes supportive care of symptoms.
Travellers who hike, camp, or undertake outdoor activities in wooded regions or city parks of endemic areas should take measures to prevent tick bites.
Tick removal: Regularly check your body for ticks and promptly remove using tweezers by grasping the tick's head and mouth parts as much as possible and by pulling perpendicular from the skin. Thoroughly disinfect the bite site with soap and water or alcohol. If travelling in an endemic area, you may want to save the tick in a zip-lock bag or empty container to have it analyzed through your healthcare practitioner.
Recommended for travellers involved in recreational activities in forested areas such as camping and hiking or working in forestry occupations, as well as long-term travellers to endemic areas.
This vaccine is available in pediatric and adult formulations in countries where Tick-borne Encephalitis is endemic. Re-vaccination is recommended every 3-5 years depending on your age if you continue to be at risk. Discuss prevention options with your health care provider or contact us to find vaccine availability at your destination.
Health risk description last reviewed and updated: September 20, 2016
Country information last updated: November 21, 2017