Most of us enjoy basking in the warm spring sun. And so do ticks. Whenever you feel like sitting down on a patch of grass or walking through a meadow, there’s a good chance there’s a tick there. Ticks are a big health problem, causing a variety of diseases, the most well-known being Lyme disease.
Eradicating ticks poses a substantial challenge due to their elusive and resilient nature. However, researchers are exploring innovative solutions, including a repellent inspired by ants.
Ticks are becoming more common
These tiny arachnids are found in more places than ever before, thanks to climate change and the expansion of areas where their wildlife hosts thrive. Taking preventive measures, like wearing long sleeves and pants, using insect repellent, and performing regular tick checks can help reduce the risk of tick bites and the ailments they can transmit.
“Ticks like a lot of the places and a lot of the times of years that we also like to be outside enjoying the weather,” says lead author Claire Gooding, a member of the SFU Gries Lab. “There’s quite a big risk of tick encounters in the summer, outdoor sports season. People often encounter them on the sides of trails.”
The rationale behind the study is pretty straightforward. Ants sometimes prey on ticks, and ticks have evolved to avoid such predators. If you could signal the ticks that their predators are around, they’ll likely avoid you — even if you are a tasty snack.
“We decided to look at ants because they are social insects and use a huge range of pheromones to communicate with one another,” says Gooding. “They’re chemically noisy. And for something that perceives the world chemically, they’re easy to predict where they’ll be, based on these pheromones.”
Ticks eavesdrop on the ants’ chemical communication system
The researchers first soiled some areas with ant pheromones and confirmed that ticks avoid them.
“They could see that there were ants and basically go, ‘I’m not going to go there, because there may be ants there, or there may be ants there again soon in the future.’”
Then, they analyzed the pheromones chemically, combining two techniques called gas chromatography and mass spectrometry to identify different substances within the pheromones. Eventually, they identified the exact compounds that the ticks were avoiding. They then worked with chemists to recreate these chemicals synthetically and recreated the experiments.
They found that the ticks had the same reaction to the synthetic pheromones and avoided them. This means the substance can be synthesized and used as a repellant for humans, either as a spray-on personal repellant or as an environmental repellent (such as woodchips) to deter ticks from coming into a park or a hiking trail.
The researchers have applied for a patent for their technology. Although it’s not clear when the product will hit the shelves, this marks a significant step forward in tick prevention strategies. This biology-based approach opens new avenues for biological pest control. By understanding more about the natural aversions ticks and other pests have, researchers can explore other ecological methods to control their populations without resorting to harsh chemical pesticides.
In the United States alone, approximately 30,000 cases of Lyme disease are reported to the CDC annually, though actual numbers are likely much higher, potentially as many as 476,000 cases each year according to recent estimates. Ticks also transmit other diseases like Rocky Mountain spotted fever, anaplasmosis, and babesiosis, which together contribute to several thousand more illnesses each year.
The study was published in the journal Royal Society Open Science.
