What to know about tick-borne encephalitis

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TBE happens when the virus, which is part of the Flaviviridae family, enters a person’s body. In most cases, a person may not know they have the virus as it generally does not cause any symptoms.

However, in severe cases, TBE can affect the central nervous system. This can result in long-term neurological symptoms. It may even be fatal.

The main way that TBE transmits is when a tick with the virus bites a person. A tick may remain on the skin for several days.

The World Health Organization (WHO) states that a person may come into contact with a tick in forests up to an altitude of around 2,000 meters.

In rare cases, a person may develop the infection if they eat or drink dairy products, such as unpasteurized milk or cheese, that have come from a goat, sheep, or cow with the infection.

TBE does not transmit from person to person.

Learn more about tick bites.

TBE does not occur in the U.S.

There are around 10,000–12,000 clinical cases of TBE each year. They are most likely to occur in the following places:

• northern, eastern, central, and western Europe
• northern China
• Mongolia
• the Russian Federation

The risk of TBE in the United Kingdom is low. In England, there have only ever been reports of two probable cases, which occurred in 2019 and 2020.

It is best for a person to contact a doctor before going abroad to ask about the risk of TBE in the place they are traveling to and whether the doctor recommends getting a vaccine to prevent the infection.

According to the WHO, TBE most commonly has an incubation period of 7–14 days, though it can be anywhere from 2–28 days. This means it can take this long for symptoms to appear.

It states that most people do not experience any symptoms. If they do appear, they may occur in two phases:

Phase one

The first phase typically lasts around 1–8 days and can include cold-like symptoms such as:

• headaches
• fatigue
• malaise or generally feeling unwell
• a fever of 100.4ºF (38ºC) or above

Phase two

Around 15% of people will experience a second phase of symptoms, which can include central nervous system involvement. These can include:

• a fever exceeding 104ºF (40ºC)
• meningitis, which can cause a headache, fever, and a stiff neck
• encephalitis, which can cause confusion, drowsiness, and sensory disturbances
• myelitis, which is inflammation of the spinal cord
• radiculitis, which refers to nerve pain

If a person develops encephalitis, this can cause paralysis. The condition is fatal in about 1% of cases where the person experiences a neurological condition.

To assist with reaching an accurate diagnosis, a doctor may begin by asking questions about a person’s symptoms, taking a complete medical history, and performing a physical examination.

If they suspect TBE, they may also ask questions about a person’s travel history.

They may order blood tests or spinal fluid tests to confirm the diagnosis. This can also help rule out other possible causes.

There is no specific medication for the treatment of TBE. To provide relief and encourage recovery, a doctor may recommend:

• resting as much as possible
• getting enough fluids
• taking over-the-counter pain relief medication

In severe cases, hospitalization may be necessary. A person may require specific treatment for encephalitis, meningitis, or meningomyelitis. The doctor can advise on what this involves and how long they may need to stay in the hospital to recover.

It is best for a person to remove a tick as soon as possible once they notice it on their skin. The National Health Service (NHS) of the U.K. advises following these steps:

1. Avoid squeezing the tick, as this might release some of the virus.
2. Grab onto the tick as close to the skin as possible using a pair of tweezers or a specific tick removal tool.
3. Pull upward firmly and slowly to reduce the risk of leaving part of the tick behind.
4. Clean the area of the bite with soap and water or antiseptic.

Learn more about removing a tick.

The Food and Drug Administration (FDA) approved the TICOVAC vaccine for use in the U.S. in 2021. It has been in use in Europe for more than 20 years.

The Centers for Disease Control and Prevention (CDC) recommend a person gets the vaccine if they are traveling from April to November in areas where TBE is likely, as this is when ticks are most active.

It may be particularly important to consider getting the vaccine if people plan on taking part in activities such as:

• camping
• hiking
• hunting
• fishing
• birdwatching

In addition to the vaccine, a person can take various steps to reduce their risk of TBE. These can include:

• not consuming unpasteurized dairy products
• wearing protective clothing such as trousers, long sleeves, and closed footwear in places where they may come into contact with ticks
• inspecting the body, clothing, pets, and outdoor gear regularly for any ticks
• removing ticks as soon as possible
• showering as quickly as possible after being outdoors

Learn more about preventing tick bites.

Below are answers to some commonly asked questions about TBE.

What are the first symptoms of tick-borne encephalitis?

While most people with TBE do not experience symptoms, those who do will likely initially experience a headache, fever, fatigue, and a general feeling of being unwell.

What is the survival rate of people with tick-borne encephalitis?

According to the Encephalitis Society, TBE is fatal in less than 2% of cases.

This can depend on the subtype of TBE, with the Far Eastern subtype being the most severe. Some people will recover completely from the condition, while others may experience long-term complications such as paralysis, speech difficulties, tiredness, and cognitive issues.

Is tick-borne encephalitis found in the US?

TBE does not occur in the U.S. It mainly occurs in parts of Europe, northern China, Mongolia, and the Russian Federation.

Tick-borne encephalitis (TBE) is a viral infection a person may develop from a tick bite. In rare cases, they may also develop the condition after consuming unpasteurized dairy products from an animal with the infection.

In most cases, TBE is asymptomatic. When symptoms do occur, they can resemble those of a cold. Some people will go on to experience more severe symptoms affecting the central nervous system.

Rest, fluids, and OTC medications may help a person find relief from TBE. They can also take steps to prevent the infection, such as getting the vaccine before traveling and removing any ticks as early as possible.

It is best to contact a doctor if someone has concerns about TBE. They can advise on the risk of TBE and order tests to confirm the diagnosis if they suspect a person has the virus.