Sand flies: small and mean
and Martina Feichter, medical editor and biologistLuise Heine has been an editor at since 2012. The qualified biologist studied in Regensburg and Brisbane (Australia) and gained experience as a journalist in television, in the Ratgeber-Verlag and in a print magazine. In addition to her work at , she also writes for children, for example for the Stuttgarter Kinderzeitung, and has her own breakfast blog, “Kuchen zum Frühstück”.
More posts by Luise HeineMartina Feichter studied biology with an elective subject pharmacy in Innsbruck and also immersed herself in the world of medicinal plants. From there it was not far to other medical topics that still captivate her to this day. She trained as a journalist at the Axel Springer Academy in Hamburg and has been working for since 2007 - first as an editor and since 2012 as a freelance writer.
More about the experts All content is checked by medical journalists.
Sand flies target our blood. And in return, they often leave dangerous pathogens behind for their victims - also in Germany.
Two millimeters tall, with fine wings, beige bodies and black button eyes - sandflies don't look like they can spread fear and terror. But they can be mean, especially in the tropics and subtropics, but also in the Mediterranean region. Because there the small bloodsuckers can transmit an infectious disease that can be fatal under certain circumstances: leishmaniasis.
The disease is caused by scourge-bearing protozoa (leishmania) that live as parasites in their hosts. It occurs in different forms:
- Cutaneous leishmaniasis: Only the skin is affected here. The disease is also called an Aleppo bump or Orient bump.
- mucocutaneous leishmaniasis: The parasites have attacked the skin and mucous membranes (especially in the nasopharynx) and subsequently spread to organs in the chest (such as the larynx, trachea)
- Visceral leishmaniasis: The parasite infestation here extends to internal organs and structures (such as the spleen, liver, lymph nodes), and more rarely to the skin. This form is also called kala-azar and can be fatal if left untreated.
How leishmaniasis progresses in individual cases depends on the type of leishmania and the state of the patient's immune system.
Death from anemia
Leishmaniasis can develop very differently from person to person. With the dangerous visceral leishmaniasis, those affected often feel tired and weak and have a fever. The liver and spleen are enlarged. When checking the blood values, pancytopenia becomes apparent - the simultaneous lack of white blood cells (leukocytes), red blood cells (erythrocytes) and platelets (thrombocytes). It occurs when the parasite interferes with blood production in the bone marrow.
The lack of erythrocytes causes severe anemia, which is difficult to control. In the worst case, visceral leishmaniasis leads to death.
Dogs as a pathogen dead end
Leishmaniasis also occurs in Germany. The illness is not notifiable, but the Robert Koch Institute assumes around 20 illnesses per year. Most infections are brought in from abroad. Occasionally people in this country get infected - from dogs. The beloved pets are often allowed to go on vacation to southern countries and come back with the dangerous travel souvenir. In addition, more and more infected dogs are being adopted from epidemic countries. So far, however, the leishmanias in sick dogs have stuck in a dead end.
No taxi, no illness - right?
Because the pathogens are dependent on being transported from one host to the next by sandflies taxi. No taxi, no illness - a simple equation, actually. However, this is no longer working in Germany - thanks to global warming, the heat-loving insects can now also spread in Central Europe:
The first sand flies were discovered in Germany in 1999, and the first sand flies breeding site was found in 2001/2002. Further locations of the pests have now been added, especially in Baden-Württemberg and Rhineland-Palatinate and mainly within cities and villages. Sand flies have also been discovered in other Central European regions (such as France, Belgium and Austria).
In Germany, however, we don't seem to have to worry about leishmaniasis at the moment: In this country, the sandflies species are at the moment Phlebotomus mascittii wide. It does not necessarily depend on a blood meal for reproduction - bad conditions for leishmanias. These are only transmitted when a sandfly first stings an infected person (human or animal) and then a healthy person, to whom the flagellates can pass it on.
But what sand flies can already transmit in Germany are viruses - such as those that cause Tuscany fever (also called phlebotomus fever or sand flies fever). This is a flu-like illness that can cause meningitis.
Experts assume that with climate change, more species of sand flies and with them pathogens will increasingly come to Germany in the future.
Mosquito repellent on the Mediterranean
German citizens who like to travel should always think of the possibility of leishmaniasis in southern regions such as Italy or Mallorca. Careful protection against mosquito bites can reduce the risk of contracting leishmania (or other pathogens). This means: wear long trousers and long-sleeved clothing and use mosquito repellants. You should also provide your sleeping area with a mosquito net - this helps to keep the crepuscular and after-active sand flies at bay!
