The sun is shining, birds are chirping and the scent of flowers is in the air: a bike tour in summer could hardly be more beautiful. But what was that? A soft clacking on the helmet reveals a collision. Perhaps a bug that has flown away?
Seconds later, there is no longer any doubt, because you can feel it crawling on your scalp: An insect has got into the helmet and is trapped in one of the ventilation holes. Shaking your head doesn't help - has it got tangled up in your hair? A careful shake of the helmet is followed by a stinging pain, which spreads burning pain across the scalp. A hot throbbing sensation spreads - ouch!
Bees or wasps in helmets are relatively high up on the list of the most unpleasant incidents for cyclists. Because if the animals feel threatened, they sting in panic. "Every second person is stung by a bee, wasp or hornet at least once in their life," says Prof Dr Bettina Wedi, an allergologist who heads the relevant department at Hannover Medical School. "The stings themselves are not dangerous, even the amount of venom from several stings is not a problem." Sayings such as "Three hornets kill a person, seven kill a horse" are therefore "absolute nonsense", says the doctor. Only if there is an allergy can even a single sting lead to death.
Shock from protein
Most people react to stings from "hymenoptera" - the biological order of bees, wasps, hornets and bumblebees - with painful swelling, reddening of the skin and itching. This is not pleasant, but harmless compared to an allergy. Scientists estimate that up to 7.5 per cent of Europeans are allergic to proteins in the venom of certain insects. And then it can become dangerous: According to the European Centre for Allergy Research Foundation (ECARF), insect bites are among the most common triggers of "anaphylactic shock".
It is unclear why an allergy develops in the first place: "Anyone can develop one at any time," says the allergist. However, because wasp stings are more common than bee stings, allergic reactions to wasp venom are more frequent. "About one in four is severe," says Wedi, who is also the section spokesperson for dermatology at the German Society for Allergology and Clinical Immunology.
Antidote: Adrenalin
It is estimated that there are around 2.5 million people living in Germany for whom a sting can be dangerous. If the venom only causes skin reactions such as a rash, it is a first-degree allergy. From grade two onwards, slight shortness of breath and circulatory problems are added. Grade three is accompanied by severe breathing problems and often an asthma attack or even unconsciousness. Doctors speak of a fourth-degree allergy when the insect venom has caused fatal respiratory and cardiac arrest. "Anyone who develops allergic symptoms to a sting for the first time on a bike ride should not continue cycling, but rather get help," advises Wedi. Physical exertion can exacerbate the symptoms. "If wheals form on the skin and breathing problems occur, call an ambulance," says the doctor.
Always with you in case of allergy: emergency kit
Cyclists who know that they are allergic to insect bites should always carry an emergency kit prescribed by a doctor. It fits in your jersey pocket and contains an antihistamine and cortisone - preferably drinkable because it works faster - as well as an auto-injector with adrenaline. Allergist Wedi advises: "If you develop more than just skin symptoms, you shouldn't be afraid to inject the adrenaline into your thigh muscle - you can't go wrong with that."
If there is no allergy, it can still be dangerous: if the insect gets into the mouth, stings the tongue or throat and these then swell up and obstruct the airways. Important to know: After a bee sting, it is possible that the stinger and venom blister may remain stuck in the skin. Carefully flick it away with your fingers - and do not touch it with two fingers: Finger pressure can cause the venom blister to deflate, which worsens the symptoms. Cooling helps to relieve the pain - preferably immediately, at the latest when you get home. If you have a lot of stings, Wedi recommends taking antihistamine tablets from the pharmacy.
To the doctor after an insect bite
A visit to the doctor is necessary if the swelling around the puncture is more than ten centimetres in diameter or if fever and other general symptoms are present. "Anyone who has developed allergic symptoms should also see a doctor," explains Dr Bettina Wedi. The best therapy is then hyposensitisation, "which is expensive, but can provide effective protection against anaphylaxis for almost all those affected".
Anyone who develops allergic symptoms should see a doctor.
Do not scratch and avoid some foods
However, most people are only bothered by itching. Dr Daniela Greiner-Krüger, dermatologist and founder of "MediCorium", a centre for dermatology and aesthetics in Oberursel, knows why this occurs in the first place. "An insect bite causes histamine to be released in the skin, which causes itching." Scratching only makes it worse, warns the doctor: "Mast cells then migrate into the tissue, which intensifies the itching." Greiner-Krüger advises paying attention to your diet the evening after an itchy bite: "If you eat foods that contain histamine, it makes the itching worse." People who have been stung should therefore avoid tomatoes, strawberries, tuna, salmon, shrimps, salami, cheese or wine for the time being.
It is helpful to distract the brain from the itching with another stimulus, such as the cold of a cool pack or ointments with menthol, which mimic the cooling effect. "Creams with capsaicin from chilli are interesting," says Greiner-Krüger. "It burns and bites after application, but this is a different, more pleasant stimulus than the itching."
Prevent insect bites
Cyclists should try to prevent stings from happening in the first place by wearing a helmet with a net or light headgear underneath and not leaving bottles of sweet drinks open. "You shouldn't take breaks next to rubbish bins, fallen fruit and nests," advises allergist Bettina Wedi. Just as little as on a clover meadow, because "there are almost always bees there". Bad luck for cyclists: Wasps not only love hairspray and some perfumed deodorants, but also the smell of sweat. However, there is no clear scientific evidence that colourful clothing attracts the animals.
The German Nature and Biodiversity Conservation Union (NABU) recommends that wasps should never be swatted away or blown at with frantic movements - otherwise they will feel threatened and defend themselves by stinging. If one gets caught in your helmet, the most important thing is to keep calm. If you stop slowly, carefully remove the head protection with calm movements and do not reach into your hair with your hand, you are probably in luck: the wasp is free, flies away and will not disturb your early summer bike ride any further.
What else stings:
Mosquito bites are not dangerous in this country - for the time being: climate change means that living conditions in Europe are becoming increasingly favourable for the Asian tiger mosquito. In late summer 2019, the Robert Koch Institute reported that the bloodsucker transmitted West Nile fever in Germany for the first time. If the species continues to spread, it could also cause chikungunya, dengue and yellow fever in the future, according to the Federal Environment Agency.
Ticks that could bite cyclists during breaks transmit Lyme disease and tick-borne encephalitis (TBE) in risk areas. Outdoor sports enthusiasts from Bavaria, Baden-Württemberg, southern Hesse, south-eastern Thuringia and Saxony should therefore be vaccinated against TBE. There is no vaccination against Lyme disease. Anyone who crosses tall grass or bushes during a pit stop should check for ticks after the ride.
The best tips for avoiding insect bites on cycle tours
You can't really prevent insect bites when cycling - but at least those cyclists who are prone to allergic reactions should take heed of what they can do to prevent them.
- Helmets with thinly barred ventilation openings reduce the risk of insects getting caught in your hair.
- Shirts with high and closed collars block the airflow to the neck and upper body.
- Glasses with large-format and flat lenses protect the eyes and forehead. If it does happen: itch-relieving substances are available from pharmacies, e.g. as a balm in stick form for your jersey pocket. Allergy sufferers should always carry an emergency kit with an adrenaline injection prescribed by a doctor.
And the general rule for buzzing bees and wasps is: stay calm, don't swat them away and don't blow at them!
