How does a black fly bite?

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It doesn't bite, it bites: the black fly. There are more of these bloodsuckers in hot summers. How to recognize their bites, how to treat them, and how to protect yourself.

Status: May 17, 2021

The black fly is a small humpbacked fly with sharp teeth. It is around two to six millimeters tall and at first glance looks like a normal fly. The insects originally come from Scandinavia. There are now around fifty different species known in Germany. Most black flies live in rural areas near rivers and streams. This is where you lay your eggs in spring. Because the larvae develop best at high temperatures and high humidity, there are more black flies in hot summers.

This is how the black fly bites

Small and hardly noticeable when it lands on our skin - the black fly.

Basically, black flies prefer to bite grazing cattle, cows and horses. Every now and then, however, it also catches people. The problem: the mosquitoes fly noiselessly at people without arousing a feeling of being touched. In contrast to normal mosquitoes, black flies are so-called "pool suckers" and not "stick suckers". This means that the mosquito bites a small wound in the skin where the blood collects, which it then sucks off.

Blackfly bites - that's how dangerous they are

In principle, black flies are not dangerous. However, the black fly's direct contact with human blood increases the risk of infection. Often bacteria only get into the wound by scratching. In the worst case scenario, blood poisoning can develop. Therefore, you should urgently see a doctor with these complaints:

"Symptoms are very strong swellings or red stripes that develop from the puncture point towards the body. Symptoms such as fever, chills and general malaise would be even worse. One should definitely see a doctor with such symptoms. Those affected should of course also have circulatory reactions to see a doctor. "

Prof. Ulf Darsow, senior physician at the Clinic and Polyclinic for Dermatology and Allergology at the Technical University of Munich

Shortly after the bite, the mosquito's saliva numbs the wound and prevents the blood from clotting. Everything that can be felt and seen is a small point of blood. However, after a few minutes, a black fly bite can become very painful. Swelling and small bruises are the result. The bruises are caused by the anticoagulant secretion of the black fly.

Every now and then there are also allergic reactions to the stings. In our part of the world, there is no need to fear the transmission of contagious diseases with this insect.

Treat black fly bites

If you are bitten by a black fly, you should cool the wound. Anti-allergic gels or creams containing hydrocortisone can also help to suppress the itching. It is important not to scratch the sting, this will prevent infections.

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The positive news: black flies never invade homes or buildings. The danger of being bitten only exists outside. This is why you should be especially careful in nature and near rivers. We recommend wearing long clothes and closed shoes. Because black flies, unlike normal mosquitoes, cannot bite through fabric. In addition, normal mosquito repellent also helps.