Tick-Borne Encephalitis on the Rise: What to Know in Belgium

Health authorities in Belgium are warning that tick-borne encephalitis (TBE) — a viral infection that can cause severe brain inflammation — is on the rise across Europe. While Lyme disease remains the more commonly known tick-borne illness, TBE presents a distinct and potentially more serious threat, with no specific antiviral treatment available and the risk of life-long neurological damage.

According to a report by VRT NWS, the virus is expanding its geographic range across the continent, and health experts are urging travelers to forested areas in endemic regions to consider vaccination.

What Is Tick-Borne Encephalitis?

TBE is a viral infectious disease affecting the central nervous system, caused by the tick-borne encephalitis virus (TBEV) — a flavivirus transmitted by the bite of infected Ixodes ricinus ticks, the same species that transmits Lyme disease.

Unlike Lyme disease, which is bacterial and treatable with antibiotics, TBE is viral and has no specific cure. As VRT NWS reported in a detailed June 2026 feature, the disease progresses in two phases. The first phase brings flu-like symptoms: fever, headache, and muscle pain. After a brief remission, approximately one in three patients enters a second phase involving neurological complications.

“Tick-borne encephalitis can lead to brain inflammation: paralysis, severe tremors, epilepsy, decreased consciousness, and in the worst case even death,” said infectious disease physician Steven Van Den Broucke in the VRT NWS report.

TBE in Belgium: A Growing Concern

Belgium is now classified as an “affected” country by the European Centre for Disease Prevention and Control (ECDC). The first confirmed autochthonous (locally acquired) human cases were diagnosed in 2020, when three patients were identified by the Institute of Tropical Medicine in Antwerp.

Since then, case numbers have remained low but persistent. According to The TBE Book (9th edition, 2026), Belgium recorded 2 cases in 2021, 2 in 2022, 4 in 2024 (with 3 likely autochthonous), and 3 in 2025. All patients with confirmed autochthonous infections in 2024 were hospitalized with neurological symptoms.

A significant milestone came in May 2024, when the TBE virus was detected for the first time in ticks collected in Belgium — at a location in southern Belgium where an autochthonous patient had been bitten in 2020. Sequencing revealed that the strain shared greater similarity with a strain found in Finland than with the Dutch Salland strain, according to research published in Parasites & Vectors.

Why Is TBE Spreading?

Several factors are driving the expansion of TBE across Europe. Climate change is allowing ticks to remain active for longer periods, extending the traditional risk season beyond spring and summer. Increased forest cover and growing wildlife populations — particularly deer and wild boar, which serve as hosts for adult ticks — are also contributing to larger tick populations.

As Knack magazine reported in April 2026, seroprevalence studies in Belgian wildlife confirm that the virus has been circulating for years. Approximately 22% of wild boars in Flemish Brabant carry antibodies against TBEV, and seropositive cattle, sheep, and roe deer have been detected across the country.

Key Differences from Lyme Disease

Many people associate tick bites primarily with Lyme disease, but TBE differs in critical ways:

Transmission is immediate: Unlike Lyme disease, which typically requires a tick to be attached for more than 12 hours, TBE virus can be transmitted almost immediately after a tick bite.
No visible rash: TBE does not produce the characteristic “bull’s-eye” rash associated with Lyme.
No treatment: While Lyme disease can be treated with antibiotics, TBE has no specific antiviral therapy — only supportive care for symptoms.

“Almost 50% of tick bites are contracted in one’s own garden,” noted biologist Käthe Robert of the University of Antwerp in the VRT NWS report, emphasizing that ticks are not only a concern for hikers and campers.

Vaccination: The Best Protection

A highly effective vaccine exists for TBE. The FSME-IMMUN vaccine (manufactured by Pfizer) offers more than 99% protection, but it requires a multi-dose schedule.

“There is a vaccine with more than 99% protection, but it requires a build-up schedule,” Van Den Broucke explained. “You need multiple doses, the first two of which must be before your trip.”

The vaccine costs approximately €40 per dose and is not reimbursed in Belgium. The Superior Health Council currently recommends vaccination only for travelers spending more than four weeks in forested areas of endemic countries during tick season, and for laboratory workers handling the virus.

Risk Areas for Travelers

TBE-endemic regions in Europe include Austria, Switzerland, Germany, the Dolomites in Italy, the Czech Republic, Hungary, Poland, the Baltic states (Estonia, Latvia, Lithuania), and parts of Scandinavia (Sweden, Finland, Norway). In parts of Central and Eastern Europe, up to 30% of ticks in heavily infected areas carry the virus.

A more dangerous Far Eastern subtype of TBEV, with a mortality rate of up to 35%, circulates in parts of the former USSR and Central Asia, making vaccination especially important for travelers to those regions.

Practical Prevention Tips

Health authorities recommend the following precautions:

Wear covering clothing, even in parks and gardens
Tuck trousers into socks
Use insect repellents containing DEET
Check your entire body after spending time outdoors, especially in skin folds
Remove ticks promptly using fine-tipped tweezers or a tick removal tool

What’s Next?

While the risk of acquiring TBE within Belgium remains very low, the virus is clearly establishing a foothold. The detection of TBEV in Belgian ticks in 2024 marks a turning point, and health authorities are closely monitoring the situation. Whether Belgium will update its vaccination recommendations in light of these developments remains an open question.

For now, the most important message is awareness. As the VRT NWS report underscores, travelers to endemic regions should consult their healthcare provider about vaccination well before departure — and everyone spending time outdoors should take tick prevention seriously.

The ECDC continues to track the spread of TBE across Europe, and with climate change expected to further expand the range of tick-borne diseases, this is a public health issue that is unlikely to fade.