Tick-born encephalitis
Updated: 03.08.2023
Approved by: General Practitioner, Alice Pan
Tick-born encephalitis (TBE) is a disease of the central nervous system caused by a virus. This can affect humans and is transmitted from ticks. The disease must not be confused with Lyme disease. The disease is not contagious between people.
Symptoms
The course of the disease is divided into two phases;
- 1st phase: Influenza-related illness with fatigue, muscle pain, fever, and reduced general condition. Headaches and dizziness are not uncommon. This lasts for 4-7 days. In 70% of those infected, symptoms regress and people recover. For the remaining 30%, the disease develops into the 2nd phase.
- 2nd phase: The person may experience a new episode of fever and, in addition, symptoms from the central nervous system. This can be; increased headache, vomiting, change in mental status, movement disorders, vomiting, and in severe cases paralysis and speech difficulties. These patients need treatment in the specialist health service.
The diagnosis is confirmed with blood tests or a sample from cerebrospinal fluid.
Occurrence
Ticks carrying the TBE virus live in Europe, including the UK, and Asia. The UK has a low risk. The disease is more widespread in Eastern Europe. Most of the infection takes place in the months of April-September.
It takes around 14 days from the time of infection until the disease develops. The disease is often mild in children but can have a serious course with disabling sequelae (late injuries) in adults and the elderly. Someone dies. Vaccines will protect against the disease.
Who should take the TBE vaccine?
Ticks occur mainly in coastal and valley areas with deciduous forests, scrub, and lush undergrowth in areas where the winters are not too long and cold. People who will be travelling in forests and fields in endemic areas, such as Eastern Europe or Asia, should consider vaccination. If you are in doubt, ask your doctor for advice.
The vaccine can be given to adults and children over one year of age. Vaccination should preferably be avoided during pregnancy or simultaneous breastfeeding but can be given if the benefits are considered to outweigh the disadvantages.
You do not need/should not take the vaccine if you;
- have had the disease, then passing infection naturally provides long-term protection. However, it is not harmful to take the vaccine even if you have had the disease.
- have a known allergy to the ingredients or have a fever
- have already been subject to exposure, for example from a tick bite
How does the vaccination take place?
The vaccine is injected into the upper arm, a so-called intramuscular injection. To achieve long-term immunity, 3 doses are required. A minimum of 1 month and preferably no more than 3 months should elapse between the first two doses. One expects to have sufficient immunity for one season after 2 vaccines. The last dose is given 5-12 months after the second. After 3 doses, 95% of those vaccinated will be protected against TBE for 3 years. After 3 years, the vaccination regimen can be repeated.
It is recommended to start the vaccination well in advance of the season to achieve 2 doses. If rapid immunization is needed, individual assessments can be made about the interval between the first 2 doses.
The vaccine is well tolerated and no serious side effects have been documented. After vaccination, you may have mild symptoms such as:
- local reaction at the injection site with slight pain and redness
- fatigue and low-grade fever
