Giant ticks in Austria - deadly pathogens detected

Dangerous pathogens were detected in one-third of the tick samples submitted in Austria. Particularly alarming: the tropical Hyalomma tick, which has also been detected in Germany .

Since the beginning of 2024, the Austrian Agency for Health and Food Safety (AGES) has been collecting tick samples from across Austria. As part of this nationwide tick monitoring program, 1,420 specimens were examined – with worrying results: As reported by " Heute ", the tropical tick species Hyalomma marginatum was detected 11 times. It is considered a potential carrier of Crimean-Congo fever, a life-threatening viral disease.

Hyalomma ticks have also been detected several times in Germany – first in 2018, and increasingly frequently since then. According to the Robert Koch Institute, Hyalomma ticks have appeared primarily in warmer regions such as Rhineland-Palatinate, Baden-Württemberg, and Lower Saxony. Their presence is closely linked to climate change.

According to "Heute," around 30 percent of the ticks submitted carried at least one pathogen—primarily Borrelia, which can cause Lyme disease. If left untreated, this infection can lead to serious long-term consequences such as paralysis, neuritis, or heart problems. There is currently no vaccination.

According to the Federal Center for Health Education, three tick species are particularly relevant in Germany:

• Ixodes ricinus (common tick) – main vector of TBE and Lyme disease.
• Dermacentor reticulatus (marsh tick) – can transmit babesiosis (“canine malaria”).
• Hyalomma marginatum – vector of tropical pathogens such as rickettsia or Crimean-Congo fever.

Eight of the eleven Hyalomma ticks discovered in Austria were examined in the laboratory. Although Crimean-Congo fever was not detected, three samples (37.5%) were infected with Rickettsia.

These bacteria cause feverish infections such as typhus or tick-borne encephalitis – diseases that, if left untreated, can be fatal in up to 40 percent of cases. Typical symptoms include fever, headache, rash, and a dark crust at the bite site ("eschar").

• Up to 2 cm in size : The tropical tick species Hyalomma marginatum is significantly larger than native ticks and has striking, striped legs.
• Distribution in Europe : In Austria, 11 specimens were submitted in 2024, in Germany the species first appeared in 2018 – since then with an increasing trend.
• High infection rate : 37.5 percent of the Hyalomma ticks examined in Austria were infected with Rickettsia – bacteria that can cause feverish infections.
• The course of the disease can be fatal : Without treatment, infections with Rickettsia are fatal in up to 40 percent of cases.
• Crimean-Congo fever : The tick is considered the main carrier of this rare but potentially fatal viral disease – so far no evidence of the virus has been found in Austria, but cases have been found in Spain and France .
• Active hunting : Hyalomma ticks actively pursue their hosts over several meters – unlike native species that lurk on the blade of grass.
• Consequence of climate change : Experts see the increasing spread as a direct effect of rising temperatures in Central Europe.