What is Tick-Borne Encephalitis (TBE)?
Tick-Borne Encephalitis is a serious viral disease that affects the brain and nervous system. Unlike most tick-borne diseases in the United States (which are caused by bacteria), TBE is caused by a virus. It's most common in Europe and Asia, but travelers to these regions should be aware of it.
⚠️ Important Note
TBE is not found in the United States, but a related virus called Powassan virus is found in North America. If you're traveling to Europe or Asia, especially during tick season, be aware of TBE.
Understanding the Virus
TBE is caused by the Tick-Borne Encephalitis virus (TBEV), which is related to other viruses like West Nile virus and dengue. There are three main types:
European Subtype
- Found in Europe (except eastern parts)
- Generally milder disease
- 1-2% fatality rate
Siberian Subtype
- Found in Siberia and Eastern Europe
- Intermediate severity
- 2-3% fatality rate
Far Eastern Subtype
- Found in Far Eastern Russia, China, Japan
- Most severe form
- 5-20% fatality rate
Source: Dobler, G., et al. (2019). Tick-borne encephalitis: From epidemiology to vaccination. Ticks and Tick-Borne Diseases, 10(6), 1012-1020.
Where is TBE Found?
TBE is found in many countries in Europe and Asia. The range is expanding due to climate change:
Europe
Countries where TBE is found include:
- Austria, Czech Republic, Germany
- Poland, Russia, Slovakia
- Sweden, Finland, Switzerland
- And many others
Note: Range is expanding to new areas and higher altitudes.
Asia
Found in:
- Russia (especially Siberia and Far East)
- China (northern and northeastern regions)
- Japan (Hokkaido and northern Honshu)
- Mongolia
Source: CDC - Tick-Borne Encephalitis | European Centre for Disease Prevention and Control (ECDC). (2023). Tick-borne encephalitis - Annual Epidemiological Report 2022.
How TBE is Spread
TBE can be transmitted in two main ways:
1. Tick Bites (Most Common)
- Primary way TBE is spread
- Virus can be transmitted within minutes of tick attachment
- Much faster than bacterial diseases like Lyme disease
- Vectors: Ixodes ricinus (Europe) and Ixodes persulcatus (Asia)
2. Raw Milk (Rare but Possible)
- Can be spread by drinking unpasteurized milk
- From infected goats, sheep, or cows
- Outbreaks have occurred in several European countries
- Prevention: Pasteurize or boil milk before drinking
💡 Important
Unlike Lyme disease which requires 24-36 hours of tick attachment, TBE can be transmitted within minutes. This makes prevention even more critical!
Source: CDC - Tick-Borne Encephalitis
Symptoms of TBE
TBE symptoms typically occur in two phases. Many people recover after the first phase, but about 20-30% develop the more serious second phase.
First Phase (7-14 days after tick bite)
This phase lasts 2-7 days and feels like the flu:
- Fever
- Headache
- Fatigue
- Muscle aches
- Nausea and vomiting
Good news: Symptoms may go away completely, and you might think you're better. But then...
Second Phase (After 1-20 day break)
About 20-30% of people develop this serious phase:
- High fever
- Severe headache
- Neck stiffness
- Confusion
- Drowsiness
- Paralysis
- Seizures
- Coma
This phase affects the brain and nervous system - it's a medical emergency!
Source: CDC - Tick-Borne Encephalitis
Complications and Long-Term Effects
TBE can cause serious, long-lasting problems, especially if the second phase develops:
⚠️ Serious Complications
Up to 50% of people who develop the neurological phase may have long-term problems:
- Memory problems and cognitive impairment
- Concentration difficulties
- Balance problems
- Speech difficulties
- Sleep disturbances
- Depression
- Permanent paralysis (in severe cases)
- Death (1-2% with European subtype, 5-20% with Far Eastern subtype)
Source: CDC - Tick-Borne Encephalitis
Prevention: Your Best Defense
Since TBE can be transmitted so quickly (within minutes), prevention is absolutely critical. There are three main ways to protect yourself:
Vaccination is the most effective protection against TBE. Image: Unsplash
1. Vaccination (Most Effective)
Vaccines are available in many countries where TBE is found:
- Highly effective - Best protection available
- Multiple doses needed - Usually 2-3 doses for full protection
- Booster shots - Needed every 3-5 years to maintain protection
- Recommended for: People living in or traveling to TBE areas
Important: Talk to your doctor well before traveling to TBE-endemic areas. You need time to complete the vaccination series.
Source: Dobler, G., et al. (2019). Tick-borne encephalitis: From epidemiology to vaccination. Ticks and Tick-Borne Diseases, 10(6), 1012-1020.
2. Avoid Tick Bites
In addition to vaccination, take measures to avoid tick bites:
- Use tick repellents on skin and clothing
- Wear protective clothing when in tick-prone areas
- Avoid tick-infested areas when possible
- Perform regular tick checks after outdoor activities
- Remove ticks promptly if found
3. Avoid Raw Milk
In endemic areas, avoid consuming raw milk from goats, sheep, or cows, as it can transmit TBE.
Treatment
There is no specific antiviral treatment for TBE. Treatment focuses on:
- Supportive care
- Management of symptoms
- Hospitalization for severe cases
- Rehabilitation for neurological complications
Prevention through vaccination is the best approach, as treatment options are limited.
Risk Factors
Factors that increase the risk of TBE include:
- Living in or traveling to TBE-endemic areas
- Spending time in tick-prone environments (forests, grasslands)
- Outdoor activities during tick season (typically spring through fall)
- Not being vaccinated in endemic areas
Travel Considerations
If you're planning to travel to TBE-endemic areas:
- Consult with a healthcare provider about TBE vaccination
- Be aware of TBE risk in your destination
- Take preventive measures to avoid tick bites
- Know the symptoms and seek medical attention if they develop
Important Note
TBE is different from other tick-borne diseases like Lyme disease. While Lyme disease is caused by bacteria and can be treated with antibiotics, TBE is caused by a virus and has no specific antiviral treatment. Prevention through vaccination and tick avoidance is essential.