Diseases
Ticks are spreading to new areas
Fewer TBE cases were registered in Germany last year. Photo: Marijan Murat/dpa
© dpa-infocom GmbH
They lurk in the grass, suck blood and can transmit dangerous pathogens: ticks are penetrating into completely new regions in Germany. Climate change is helping the brown crawlies.
Ticks are spreading in more and more regions in Germany – and with them the risk of diseases such as meningitis TBE. Tick experts presented new research results at a press conference at the University of Hohenheim in Stuttgart on Tuesday.
Accordingly, TBE cases are increasingly being registered at altitudes of 500 to 700 meters. The researchers assume that the ticks are becoming increasingly too warm in the lower-lying areas. “Ticks get too uncomfortable in valleys,” said biologist Rainer Oehme from the Baden-Württemberg State Health Office.
Less TBE diseases in 2021
The number of TBE diseases registered nationwide fell significantly last year – according to current data from the Robert Koch Institute from 712 to 417. However, this is still a comparatively high value, emphasized Gerhard Dobler, head of the National Consultative Laboratory TBE at the Institute for Microbiology of the Bundeswehr in Munich. The number fluctuates significantly from year to year, depending on the weather and leisure activities, among other things. In the record year 2020, the corona virus drove people into the countryside. The little animals are already very active again, warned the parasitologist Ute Mackenstedt from the University of Hohenheim.
Typical habitats for ticks include sparse forests and forest edges as well as areas with tall grass or bushes. The risk of infection is particularly high in Bavaria, Baden-Württemberg, southern Hesse and south-eastern Thuringia. Even if most people still get TBE there, the number of TBE cases fell in Bavaria and Baden-Württemberg in 2021 in particular. However, there was no decrease in federal states further north, such as Saxony and Lower Saxony. TBE is spreading more and more in northern Germany, said Dobler. More research and an adjustment of the vaccination strategy are therefore needed.
The Robert Koch Institute is showing more and more TBE risk areas – most recently districts in Brandenburg, Saxony and North Rhine-Westphalia. There are already 175 such risk areas in Germany – nationwide, more than 40 percent of all districts are affected.
More tick species registered
More and more species of ticks are spreading in native regions. The parasitologist Mackenstedt examined 8,000 tick finds. Result: The so-called Auwald tick, which can also transmit TBE, is now spreading nationwide. In contrast to its relatives, which have been established for years, it actively searches for hosts that it could sting at temperatures of around four degrees. Tropical ticks of the genus Hyalomma also appear again and again – they are introduced by migratory birds in Germany. With increasingly dry, warm summers, this tick can become a regular guest in this country, according to the researchers. Tropical ticks can transmit dangerous pathogens such as tick spotted fever.
TBE stands for tick-borne encephalitis. Infection is often mild. In the first phase there are often flu-like symptoms: you have a fever, you are knocked out, your head and limbs hurt. Inflammation of the brain, the meninges or the spinal cord can follow later – so there is a risk of severe courses. Once the disease has broken out, only the symptoms can be treated. The disease is fatal for around one percent of patients. In risk areas, the probability of infection after a tick bite is 1 in 50 to 1 in 100.
There is a vaccination against TBE, but not against Lyme disease, which is also transmitted by ticks and occurs nationwide. Dobler called for TBE vaccination on Tuesday. Again and again one sees severe cases in children. In regions that are particularly affected, such as Ravensburg, campaigns must be carried out to increase the willingness to vaccinate.