An insect bite is especially common during the warm months. While most insect bites are banal events, an insect bite can also be associated with acute complications or those that occur after a certain period of time. While elsewhere a dreaded consequence of an insect bite is the transmission of diseases such as malaria, fortunately in our latitudes these diseases play hardly any role.
For us, the complications of an insect bite are on the one hand the allergic reaction and on the other hand the inflammation. Especially bee and wasp stings can cause symptoms of an allergy. In case of severe allergic reactions, which fortunately are rare, the insect sting can affect the circulatory functions, so that life-threatening complications can occur.
Such an acute situation requires immediate emergency medical attention. Fortunately, in most cases, the local reaction after an insect bite is limited to the area of the bite; inflammation. Inflammatory reactions are the body’s response to external stimuli and serve to ward off these damaging stimuli.
The local, i.e. locally limited inflammation is therefore to be regarded as a normal and meaningful reaction to an insect bite. It is used to defend against pathogens and foreign proteins contained in insect venoms or saliva. Furthermore, the healing of the resulting wound is promoted by the inflammation. Problems can cause inflammation after an insect bite, especially if they are caused by bacteria colonizing the tissue.
Symptoms
Depending on the type of stinging insect, there is no (or only slight) to severe stinging or burning pain during the bite. Signs of inflammation, beyond the pain, are redness, swelling (for example in the form of blisters or wheals) and warming of the bite site and surrounding tissue. These symptoms are basically found in all types of inflammation in the body.
Insect bites can also cause itching. This is often perceived as the most disturbing symptom after an insect bite. The inflammatory reaction can vary considerably depending on the type of insect, the personal reaction readiness, as well as previous bites.
Thus, the symptoms range from only punctiform, itchy redness to swellings of several centimeters in size. Usually these symptoms are harmless and subside by themselves after a short time. An inflammation in the case of an insect bite can become dangerous if the area around the insect bite is infected by bacteria.
If redness and swelling, often with a feeling of tension, or pronounced pain, occurs over a large area or over days, a doctor should be consulted to rule out a bacterial infection of the tissue around the bite. Pus is also an indication of a bacterial infection and should be urgently examined by a doctor. Also pronounced yellowish incrustations, which can occur especially after severe scratching.
Not only the skin and subcutis can be infected by bacteria after an insect bite. A bite in the area of the limbs can also lead to an inflammation of the lymphatic system. This phenomenon, which is often misinterpreted in the vernacular as “blood poisoning” and often leads to a visible strand-like redness and swelling of the lymph channels in the arms or legs, also requires medical treatment.
Even after tick bites (which are not actually insect bites, since ticks are arachnids), observation of the bite site should be of particular importance. The warning symptom for Lyme disease transmitted by ticks is the so-called erythema migrans. Typically, a reddening of the skin occurs at the bite site.
Over time, this redness spreads in a circular pattern, it “migrates”, i.e. migrates. The name of this phenomenon derives from this fact. Since such a characteristic appearance is not always clearly visible, a doctor should be consulted in case of doubt if the redness of the area is unclear after a tick bite or an unclear bite.
This doctor can also carry out a Lyme disease test. As the erythema migrans can sometimes regress rapidly, it may be useful to take a picture of the visible inflammation of the mosquito bite and to present the pictures to the doctor treating the patient later. Pus is an indication of an inflammatory reaction of the body.It is a yellowish liquid, which usually consists of the body’s defense cells and other dead body cells as well as bacteria.
In most cases, pus develops when there is a bacterial infection (superinfection). This can easily happen with an inflamed insect bite, as the pathogens enter the wound by scratching under the skin at the bite. In case of a suppurating inflammation caused by an insect bite, a doctor should always be consulted.
Since bacteria are responsible for the development of pus, antibiotic therapy should be initiated. The pus should also be removed mechanically. In the case of very large pus cavities, this procedure is carried out in a surgical hospital.
Small abscesses, on the other hand, can be removed by a general practitioner in private practice. After starting the antibiotic therapy, the bacterial inflammation should decrease significantly after about 48 hours. In general, various insect bites can cause circular redness, including flea bites.
However, if a circular reddening develops around the bite site, it should first be considered whether a tick bite in the last few weeks is recurrent. A red ring around the bite could be a sign of Lyme disease, a disease transmitted by ticks and caused by special bacteria (Borrelia bacteria). Typical for this is the so-called wandering redness (erythema migrans), as the redness can “wander” along the skin, i.e. change its position or size. If such a skin pattern is present, possibly with accompanying symptoms such as fever or pain, a doctor should be consulted immediately.
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