Synonyms in a broader sense
Early summer meningo-encephalitis, encephalitis, tick
Tick bite
Please also note our suitable topic: Tick bite
Definition
The TBE virus is transmitted by ticks just like borelliosis. The TBE virus occurs particularly in southern Germany, but recently it has been spreading increasingly northwards. Early summer meningoencephalitis (TBE) is an inflammation of the brain and/or meninges caused by the TBE virus, which belongs to the flavivirus family. Occasionally, the spinal cord is involved (meningo-encephalomyelitis).
Pathogen and transmission path of TBE
In Europe, the virus is usually transmitted to humans by the bite of infected ticks (most commonly Ixodes ricinus, Ixodes persulcatus). The bloodsuckers only become active from temperatures around 10 degrees and mainly in spring and early summer. However, an infection in November is still possible!
Ticks are mainly found in forests in high grass and bushes. Their main hosts are small mammals like mice (main reservoir), but also birds and deer. The viruses in the salivary glands of ticks are washed into the bloodstream with the saliva during the sucking act.
However, not every tick bite triggers an infection with the TBE virus. The longer a tick sucks, the greater the likelihood that humans will also become infected. The forcible removal of ticks from the skin also increases the risk that the pathogen is literally “squeezed out” into the bloodstream.
In rare cases, the TBE virus can also be transmitted through infected raw milk products from goats and sheep, which is particularly important in Eastern European countries. A direct infection from person to person is not possible. Epidemiology TBE only occurs in certain regions.
In many European countries, especially Austria, Eastern Europe and Eastern Siberia, there are TBE – transmitting ticks. The risk areas (two illnesses per year or five illnesses in five years) in Germany are southern Germany, the Bavarian Forest, the Black Forest and the Lake Constance region with about 90 % of the TBE cases; the Odenwald is also affected. In these areas, about 1-5% of ticks are carriers of the TBE virus.
An up-to-date list of the annually changing high risk areas (more than 25 cases of the disease in five years) can be found on the website of the Robert Koch Institute (www. rki. de).
Since the obligation to report the disease was introduced in 2001, almost 300 cases of the disease have been registered each year in Germany. This means that early summer meningoencephalitis is much rarer than Lyme borreliosis, which is also transmitted by ticks. However, it must be considered that due to the low involvement of the nervous system of 10%, many cases of the disease are not diagnosed. Children are infected less often than adults and the course is usually milder. Nevertheless, meningitis in children can also be caused by a TBE infection.
