Giant invasive ticks spreading across Switzerland this summer

Though tick season in Switzerland is always something to be aware of as you head out for a stroll or hike through the countryside, 2025 has seen a new, larger critter make its way into the fields and hills. Here’s what you need to know about the Hyalomma, the giant tick now making its home in the alpine nation.

Ticks three times the size of native species spreading in Switzerland

Though they were first detected in Switzerland in 2018, in 2025, the giant invasive Hyalomma ticks are spreading further across Switzerland this summer, having become significantly more numerous. The species, originating from Africa and the Mediterranean, is said to have spread to the cantons via latching onto migratory birds.

After the Hyalomma tick bites its prey and sucks its blood, it can reach up to two centimetres long when fully engorged - three times the size of the common ticks found in Switzerland. Unlike native Swiss species, the Hyalomma tick is not passive, waiting and latching onto passing animals and humans. Instead, these ticks actively hunt their hosts over a distance of several metres.

Fears of new diseases if invasive ticks find a home in Switzerland

"If Hyalomma ticks were to spread here, that would be bad news for the population, because this species poses a significant threat," Werner Tischhauser, Vice President of the Swiss Tick League, told the Tages-Anzeiger. The main concern is that while regular Swiss tick bites can lead to significant diseases such as Lyme disease and tick-borne encephalitis, if invasive species find a home in Switzerland, they can spread new pathogens.

For instance, Hyalomma ticks can carry Crimean-Congo Hemorrhagic Fever, which can be fatal. The meadow tick, another invasive species spreading across Switzerland, can cause Tibola syndrome (like a fever) and babesia (an infection of the red blood cells similar to malaria).

Climate change boosting the spread of invasive ticks

Both Tischhauser and accident insurer SUVA agreed that climate change has made ticks, both local and invasive, more of an issue. Due to the warmer winter, ticks can now be found high in the Swiss mountains, at over 2.000 metres above sea level. Higher average temperatures also “extend the time of year with tick activity”, Tischhauser added. 

The warmer conditions also make it more likely that invasive species like the Hyalomma will find a permanent home in Switzerland. For more information about how you should protect yourself, check out our guide to tick season in Switzerland.