Tick-borne encephalitis

Tick-borne encephalitis (TBE) is a disease caused by the tick-borne encephalitis virus. This virus is transmitted through tick bites. Another, less common method of infection is by consuming raw milk or unpasteurised cheese from infected animals, such as sheep, cows, and goats.

The TBE virus can be classified into two subtypes: Früh Sommer Meningo Encephalitis (FSME) and Russian Spring-Summer Encephalitis (RSSE). The illnesses caused by these viruses are quite similar; however, the RSSE variant, which is primarily found in eastern Russia, is often associated with more severe symptoms.

Where is tick-borne encephalitis found?

The TBE virus, along with its subtypes FSME and RSSE, is prevalent in Central, Northern, and Eastern Europe, as well as in parts of Russia and Central Asia. Ticks that are infected with the virus can be found in specific regions of Europe and Asia. In 2016, the virus was first identified in ticks in the Netherlands. However, the risk of contracting the disease in the Netherlands is low, as very few ticks are infected with the TBE virus.

What are the symptoms?

Some individuals bitten by a tick infected with the TBE virus may experience no symptoms or only mild ones. For those who do develop symptoms, tick-borne encephalitis typically occurs in two stages. After an incubation period of one to two weeks, the first symptoms appear:

• Stage 1: fever, fatigue, headache
• Stage 2: severe headache, fever, and meningitis
• Signs of paralysis (rarely)
• Neurological symptoms (rarely)

How to prevent tick-borne encephalitis

The TBE virus is transmitted to humans through infected ticks. The tick-borne encephalitis vaccination (also known as the FSME vaccination) offers over 95% protection.

It is also important to remove a tick as quickly as possible after a tick bite to reduce the risk of infection. Prevention is better than cure, so it is best to avoid being bitten altogether. Therefore, it is recommended to wear protective clothing and closed shoes, and to apply DEET to exposed parts of the skin.

More information

Would you like to learn more about tick-borne encephalitis? Please visit the information page of the RIVM here:  Tick-borne encephalitis | RIVM.