In summer, insects of all kinds (wasps, bees, mosquitoes, ticks) swarm in nature. Most native species are harmless, as long as you are not allergic to them. There is at least one exception: ticks. Their bites can transmit Lyme disease or cause tick-borne encephalitis (TBE). But have you ever heard of the “flying tick”?
What is the “flying tick”?
“Flying tick” is the popular name given to the deer fly. In reality, it is not a tick, but a small blood-sucking fly measuring three to six millimeters. When it lands on an animal or human, it often sheds its wings and moves into the hair or fur to feed on blood. They mainly attack deer and deer, but humans, dogs and horses can also be affected.
Where do deer flies live?
Deer flies live mainly in forests and their edges in Europe as well as North and Central Asia. They are mainly active in autumn, but depending on the species and weather conditions, they can be active as early as late summer. Unlike ticks, which prefer areas of bare skin, deer flies like thick hair and coats.
How do I know if I have been bitten by a deer fly?
Strictly speaking, the fly bites, although we often speak of a sting. Six to 24 hours after the bite, red, itchy papules (rash) may appear, especially on the head, neck and upper back. Burning sensations, blisters and inflammation are also possible. The itching may persist for several weeks.
Can the bite transmit diseases?
Several potential pathogens have been detected in deer flies. However, it is still unknown whether they can transmit them to humans through their bite. The suspicions relate in particular to the bacteria Bartonella schoenbuchensis. However, the available data tends to rule out this hypothesis: a study published in 2025 did not find higher levels of corresponding antibodies in German foresters, despite their frequent exposure to deer flies.
What to do if bitten?
If it is still present, remove the insect from the hair or clothing, for example using a fine comb. Then clean the bite area, disinfect it and apply cold. Avoid scratching! Scratching increases the risk of skin infection. If there is spreading redness, presence of pus, fever, severe pain or persistent symptoms, consult a doctor. Breathing difficulties, facial swelling or circulatory problems constitute a medical emergency and require immediate attention.
How to avoid bites?
In principle, insect sprays are useful, but only to a certain extent. The deer fly is particularly tenacious. The best solution is to adopt the same precautions as against ticks: cover the skin as much as possible, use a repellent and carry out a careful check after going out in the forest. Fortunately, the deer fly is more interested in animals than humans.
