Most insect bites are presented in form of puncture wounds, papule formation, localized urticaria and pruritus. These symptoms typically subside within a few hours or days. Both immunodeficiency and secondary infection after scratching may provoke more severe local symptoms. Patients infected with HIV, those suffering from mast cell disorders or lymphoproliferative diseases may present with tissue necrosis due to insect bites. Lymphadenopathy and fever may be observed. Scratching may lead to secondary bacterial infection or allow transmission of trypanosoma.

Systemic reactions are very rare, but may consist in:

• Anaphylaxis. If previous exposure to insect allergens led to mast cell sensitization, an insect bite may trigger a type I hypersensitivity reaction manifesting in severe urticaria, pruritus, vomiting, respiratory symptoms, tachycardia, hypotension and possibly anaphylactic shock.
• Serum sickness. Characteristic symptoms are malaise, fever, chills, lymphadenopathy, arthalgia and abdominal pain [9].
• Papular urticaria. Patients suffering from papular urticaria typically present with chronic skin lesions and pruritus that tend to disappear in winter but that often reappear next summer. Papules may form at a considerable distance from the causative insect bite [10].

Patients currently treated with beta-sympatholytics and angiotensin-converting enzyme inhibitors seem to be at higher risks of systemic reactions.

• Pain

  All this pain has enabled him to create the Schmidt Pain Index, comparing nonlethal insect stings and bites in the same way that the Scoville Scale ranks the heat of chile peppers. [travelandleisure.com]

  Black Widow Bites Black widow spider bite symptoms usually start 20 minutes to one hour following the bite, and can include pain, though not all people experience pain. [medicinenet.com]

  The initial bite is not painful but will eventually cause pain. Other symptoms may include a red/purple blister, rash, muscle pain, difficulty breathing, headache, fever, high blood pressure, nausea and vomiting. Sometimes an ulcer forms. [firstderm.com]

  The Therapik relieves pain and itch from bug bites and insect stings by the direct application of heat for 20-30 seconds. [therapik.com]

  Take aspirin or ibuprofen to reduce pain or swelling, as directed. A serious response to insect bites and stings should be treated as an emergency. [healthcentral.com]

• Swelling

  Symptoms Insect bites on dogs can include the following reactions: Swelling on the eyelids Swelling on ear flaps Swelling on the lips and in some cases the entire face. In this case, it is known as angiedema. [petassure.com]

  Take aspirin or ibuprofen to reduce pain or swelling, as directed. A serious response to insect bites and stings should be treated as an emergency. [healthcentral.com]

  Immediate pain and rapid swelling occur following a sting. A few children have severe reactions, –such as difficulty breathing and hives/swelling all over their body. Ticks Ticks are found in wooded areas. [healthychildren.org]

  However, it is a larger local reaction that causes swelling, generally more than 3 inches, around the sting. For example, a sting on the front of your arm could cause your whole arm to swell. [acaai.org]

  A healthy man who presented to hospital with painful swelling of the left arm following a history of insect (tick) bite developed shock and died within 48 hours. [ncbi.nlm.nih.gov]

• Severe Pain

  However, the condition worsened with increasing pain, loss of sensation, tense swelling, and severe pain to any stretch of the tissues. Thus the patient received fasciotomy followed by repeat and thorough debridement. [ncbi.nlm.nih.gov]

  But their bites can cause severe pain and swelling. [raisingchildren.net.au]

  The swelling may last a week Call Your Doctor If Severe pain persists > 2 hours after pain medicine Infected scab doesn't clear after 48 hours of antibiotic ointment. [westendpedsnyc.com]

  The swelling may last a week Call Your Doctor If Severe pain persists > 2 hours after pain medicine Infected scab doesn’t clear after 48 hours of antibiotic ointment. [tenaflypediatrics.com]

• Veterinarian

  Your veterinarian can give you tips on protecting your dog and other pets from fleas. [brunch.co.kr]

  Have pets checked by a veterinarian for possible mite or scabies infestations. Consult with a pest control professional or Board Certified Entomologist concerning identification of suspected insect or mite infestations. [citybugs.tamu.edu]

  Treat and suggest having animals treated by a veterinarian. Expect relief from symptoms within 24 hours. If no improvement or symptoms worsen, consult pharmacist or physician. Assess Benenfit: No follow-up usually required. [medsask.usask.ca]

  You can pick up a flea medication at your local veterinarian office. Bites from lice will appear in your hair. You may not be able to see them, so have a friend or family member check for you. They are red and itchy. [wikihow.com]

• Pathologist

  Both clinicians and pathologists need to be aware of this rare, rapidly fatal condition that may follow an insect bite. [ncbi.nlm.nih.gov]

  The patient’s age and relevant clinical history, in addition to the site from which the skin biopsy was obtained, should be provided to the pathologist. [doi.org]

  Medical Editor: Melissa Conrad Stöppler, MD Melissa Conrad Stöppler, MD Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. [medicinenet.com]

• Nausea

  Spiders Black widow spider bites cause muscle cramp, seizure, nausea, vomiting and rise in blood pressure. These spiders are roughly 1/3 inch wide and 1.5 inches long, counting their long legs. [firstderm.com]

  The black widow spider may cause only a mild local reaction at the bite site, but pain, stiffness, chills, fever, nausea, and abdominal pain may follow within a few hours. [skinsight.com]

  There may be nausea, vomiting, severe headache, and loss of appetite, pain in the abdomen, muscle aches and diarrhoea. After initial 2 to 5 days there may be a red rash on the wrists, forearms, palms, soles and ankles. [news-medical.net]

  Rare complications include fever, body aches, nausea, vomiting, hemolytic anemia, rhabdomyolysis, kidney failure. Read full article on brown recluse spider bites. [healthline.com]

• Abdominal Pain

  Description For those allergic to bites and stings, their skin breaks out in hives, the eyes itch, the chest and throat feel constricted, a dry cough comes on, and there is often nausea, abdominal pain, vomiting, and dizziness. [healthcentral.com]

  The black widow spider may cause only a mild local reaction at the bite site, but pain, stiffness, chills, fever, nausea, and abdominal pain may follow within a few hours. [skinsight.com]

  Call a doctor if: You have a fever, severe headache, muscle and joint pain, nausea and vomiting, abdominal pain or a red, blotchy rash that starts on your ankles and wrists and spreads across your body within a week of being bitten. 4 / 6 Bees and Wasps [sharecare.com]

  They include: Chest pain Face or mouth swelling Difficulty swallowing Difficulty breathing Fainting or lightheadedness Abdominal pain or vomiting Rash or flushing For severe reactions, first check the person's airways and breathing. [nlm.nih.gov]

• Fracture

  부위의 골절(Fracture of T3 and T4 level) S22.030 T3 및 T4 부위의 골절, 폐쇄성(Fracture of T3 and T4 level, Closed) S22.031 T3 및 T4 부위의 골절, 개방성(Fracture of T3 and T4 level, Open) S22.04 T5 및 T6 부위의 골절(Fracture of T5 and T6 level) S22.040 T5 및 T6 부위의 골절, 폐쇄성(Fracture [koicd.kr]

  Most cases are caused by trauma, fractures, surgeries, or vascular injury, while other causes are easily misdiagnosed. [ncbi.nlm.nih.gov]

• Insect Bite

  Insects may chew, bite, suck, sponge, lick and pierce with their mouthparts. Any damage inflicted with an insect's mouthparts may be referred to as an insect bite. Because mosquitos pierce and suck with their mouthparts, they cause insect bites. [symptoma.com]

  insect bite, insect bite, nonvenomous insect bite, Bite;insect, insect bites, Insect bite: (& NOS) (disorder), Insect bite: (& NOS), Insect bite NOS (event), Insect bite, Insect bite - wound, Insect bite (morphologic abnormality), Insect bite - wound [fpnotebook.com]

  Although, you may think of it as a minor insect bite, many insect bites on dogs lead to numerous reactions and dog allergies. It is important to recognize and understand the types of bites and their possible symptoms. [petassure.com]

  bite Nonvenomous insect bite of multiple sites Nonvenomous insect bite without infection Nonvenomous snake bite Thrip bite Tick bite without infection [icd9data.com]

• Urticaria

  Papular urticaria. Patients suffering from papular urticaria typically present with chronic skin lesions and pruritus that tend to disappear in winter but that often reappear next summer. [symptoma.com]

  Papular urticaria Papular urticaria is a hypersensitivity reaction, most often in a young child due to fleabites and/or mosquito bites. [dermnetnz.org]

  Insect bites and the associated hypersensitivity reactions known as papular urticaria account for a significant number of all referrals from pediatricians and dermatologists to our pediatric dermatology clinic. [ncbi.nlm.nih.gov]

  […] urticated papules - there may be a central punctum; they may be excoriated; occasionally blisters are associated bites often occur in groups; often asymmetrical more than one family member may be affected may be secondary bacterial infection papular urticaria [gpnotebook.co.uk]

• Papule

  Most insect bites are presented in form of puncture wounds, papule formation, localized urticaria and pruritus. These symptoms typically subside within a few hours or days. [symptoma.com]

  This initial lesion becomes intensely itchy after a few days to about a month, and the scratching leads to secondary skin lesions consisting of papules (solid elevations), pustules, and crusted skin areas. [britannica.com]

  An insect bite presents as one or more intensely itchy papules on a body site exposed to the insect. Insect bites often arise in crops. The papule usually subsides within a few hours. [dermnetnz.org]

  The eruptions consisted of itchy erythematous papules, nodules, plaques, and vesicles. Non-vesicular lesions were characterized histologically by normal or mildly spongiotic epidermis. [ncbi.nlm.nih.gov]

  Clinically insect bites are generally: itchy urticated papules - there may be a central punctum; they may be excoriated; occasionally blisters are associated bites often occur in groups; often asymmetrical more than one family member may be affected may [gpnotebook.co.uk]

• Eruptions

  We recommend meticulous investigation of patients diagnosed with Wells' syndrome manifesting as an insect-bite-like eruption. [ncbi.nlm.nih.gov]

• Skin Rash

  Symptoms of West Nile Virus West Nile virus, which is transmitted by infected mosquitoes, can produce flu-like symptoms, including fever, headache, stiff neck, body aches, and skin rash. [nextcare.com]

  Examples of Bug Bite Rashes A rash is an area of inflamed or irritated skin, and it can have various causes. [skincare.lovetoknow.com]

  Usually there are influenza like symptoms of fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph nodes or a skin rash. Complications include encephalitis and meningitis and may manifest with seizures. [news-medical.net]

  Spiders bite appearance Two puncture marks close together bite symptoms Widow spiders : muscle cramps and pain, increased blood pressure, sweating, skin rash Violin spiders : anemia, blood in the urine, fever, rash, nausea, vomiting and even coma (rare [orkin.com]

• Aggressive Behavior

  Particularly for bees and wasps, this sort of aggressive behavior can often anger them, or make them feel threatened, and more likely to sting you. [organicfacts.net]

• Headache

  At its most severe, it may kill surrounding tissue and cause fever, chills, and headache. Hobo Spider is a large brown spider that is active in the Pacific Northwest of the U.S. [firstderm.com]

  In addition to the classic bull’s-eye rash of Lyme disease, tick-borne illnesses can cause chills, fever, fatigue, headaches, and muscle or joint pain. [consumerreports.org]

  Other symptoms include fever, significant fatigue, body aches, stiff neck and headache. Early treatment frequently has a positive outcome. 3 / 6 Dog Tick Where: All states, but mainly North Carolina, Oklahoma, Arkansas, Tennessee and Missouri. [sharecare.com]

  Symptoms of Rocky Mountain Spotted Fever Initial symptoms may include fever, nausea, vomiting, severe headache, severe neck pain, muscle pain, and lack of appetite. [nextcare.com]

  Symptoms of Lyme disease include fever, rash, headache and fatigue. If caught early enough, the disease can be treated with antibiotics. [cbsnews.com]

Most insect bites don't require any additional diagnostic measures.

If patients present uncommon symptoms like tissue necrosis, these should guide the physician's decision regarding further diagnostic measures. They may be carried out to identify potentially underlying immunodeficiency.

Thorough anamnesis and query for possible exposure to insects may be of great help to identify the etiological agent in patients presenting with serum sickness or papular urticaria.

With regards to anaphylaxis, immediate treatment takes priority over diagnostic workup. However, patients that show severe adverse reactions to insect bites are considered to have higher risks of anaphylaxis upon getting bitten again. Therefore, the causative species and/or allergen should be identified if possible. Significant advances have been made regarding diagnostic measures such as skin tests to prove hypersensitivity to determined proteins [4] [11].

Local application of ice and possibly antihistamines may help to reduce inflammation and pruritus. The latter is of major importance to avoid scratching and subsequent secondary infection, particularly in children. Systemic treatment is not necessary in uncomplicated cases of insect bites.

In contrast, tissue necrosis and systemic symptoms do require special treatment, possibly even surgery. While antihistamines and corticosteroids is occasionally used to treat serum sickness and papular urticaria, they are routinely administered to patients suffering from anaphylaxis. Additionally, these patients may require application of adrenaline. Depending on adrenaline-mediated effects, aggressive intravenous fluid therapy to compensate for hypotension and administration of beta-sympathomimetics to induce bronchodilation may be necessary. Early intubation and oxygen supply is recommended to avoid asphyxia due to bronchospasm.

Prognosis is generally excellent. Most insect bites are little more than transient nuisances; however, severe reactions to insect bites may be associated with significant morbidity and mortality. Anaphylaxis, tissue necrosis and secondary bacterial infection may pose serious threats to human health and require immediate medical attention. The risk of an anaphylactic reaction is significantly increased in patients presenting underlying mast cell disorders [8].

As has been mentioned above, mosquitos, fleas, bugs and lice shall serve as examples for insects that may inflict bites in this article.

• Mosquitos pertain to the order of Diptera and constitute the family Culicidae. Female mosquitos dispose of mouthparts forming a proboscis that allows for penetration of human skin and sucking of blood.
• Fleas form a rather small order within the insect class, the Siphonaptera. Similar to mosquitos, they are able to pierce human skin and feed on blood.
• Bugs, or true bugs, pertain to the order Hemiptera. Of medical importance are bed bugs (family Cimicidae) and assassin bugs (family Reduviidae). They pierce and suck using their proboscis.
• Lice form the order Phthiraptera and have retractable mouthparts that are also adapted to piercing and sucking.

With the exception of the oceans, there is no place on earth that's free from insects. They can be found on every continent, even in Antarctica. However, insect populations are generally larger in hot and humid climate zones. In temperate climates, the risk of insect bites is higher during the warm summer months.

Many insect species inhabit certain geographic regions and thus, only locals and travelers may be bitten by a particular type of insect. While this also limits exposure to pathogens transmitted by insects, expansion of vectors may put additional human populations at risk. Such phenomena have been observed in mosquitos transmitting malaria and leishmaniasis, for instance [2] [3].

People pertaining to any race, gender and age group may be bitten by insects. Overall morbidity and mortality are very low, but serious complications may be observed even in patients who haven't been diagnosed with hypersensitivity previously. Such reactions may be fatal [4].

Insects either bite to access possible food sources or to defend themselves and their offspring. While biting, they expose their host or enemy to proteins contained in their saliva [5], to anticoagulants injected in order to feed more easily on blood, to local anesthetics to avoid being removed while feeding, and possibly to pathogens they serve as vectors for. With regards to the former, all kind of proteins may act as allergens and severe reactions to insect bites are almost exclusively mediated by the immune system of the patient. Usual reactions to insect bites are also evoked by the immune system and mainly comprise urticaria and pruritus as characteristic symptoms of a type I hypersensitivity reaction. This may cause the patient to scratch, which, in turn, may lead to secondary infections.

If healthy individuals are bitten by insects, the main risk for complications rests in transmission of pathogens. A plethora of viruses, bacteria and protozoa may be transmitted by biting insects. Some pathogens use distinct insect species as an unspecific carrier, while others have to complete developmental stages within determined insects.

• Mosquitos are known to transmit all kinds of pathogens. They serve as vectors for viruses (e.g., those viruses causing yellow fever, Dengue fever, West Nile fever), bacteria (mainly Enterobacteriaceae) and protozoa (e.g., Dirofilaria immitis [6], Leishmania spp., Plasmodium spp.).
• Although fleas are rarely considered when talking about vector-borne diseases today, they are of major historical importance as vectors of Yersinia pestis, causative agent of the bubonic plague. Of note, this disease is still not eradicated [7], but antibiotics have considerably reduced its dreadfulness. Fleas may also transmit Rickettsia spp. that cause typhus.
• While bed bugs are not known to transmit infectious diseases, assassin bugs serve as vectors for Trypanosoma cruzi. This protozoan parasite causes Chagas disease and is actually transmitted via the feces of the bug, but infection is largely facilitated if the patient scratches bite sites.
• Similar to fleas, presence of lice has been associated with bouts of typhus. Lice may also serve as vectors for Borrelia recurrentis and Bartonella quintana, etiological agents of relapsing fever and trench fever, respectively.

Insect bites may be prevented by minimizing exposure. Appropriate measures are particularly recommended to people living in or traveling to geographical regions where insects transmit diseases like malaria and Chagas disease. Preventive measure comprise:

• Wearing of long-sleeved clothes.
• Use of window screens and/or mosquito nets.
• Use of repellents. Insect species may be resistant to certain formulations. Up-to-date information should be consulted before deciding for any particular repellent.
• Prolonged stays in high-risk areas such as those close to stagnant waters should be avoided. This restriction may apply only to certain times of the day and year.

In order to avoid secondary infections of insect bites, patients should refrain from scratching.

Patients with a medical history of adverse reactions to insect bites should carry adrenaline pens to allow for immediate countermeasures in case of anaphylaxis. In severe cases, desensitization should be considered [12]. Spontaneous desensitization may occur while growing up [5].

Insects constitute a huge class of animals that may comprise as much as ten million species - some experts estimate even higher numbers. Animals as distinct as beetles, flies, wasps, bees, ants, moths and butterflies are all insects. They pertain to the phylum of arthropods, like arachnids do, but both classes can easily be distinguished by counting legs: Insects have six legs, arachnids have eight. Of course, there are many other morphologic and functional differences between insects and arachnids, but this method should suffice for non-zoologists.

An insect's body consists of head, thorax and abdomen, and is sustained by a hard exoskeleton. Upon closer inspection, antennae, eyes or ocelli and mouthparts may be recognized on the head. The insect's mouthparts are often used to illustrate evolution: While most insect species dispose of labrum, mandibles, maxillae, labium and hypopharynx, these organs have been largely modified to adapt to distinct forms of nutrition. Insects may chew, bite, suck, sponge, lick and pierce with their mouthparts.

Any damage inflicted with an insect's mouthparts may be referred to as an insect bite. Because mosquitos pierce and suck with their mouthparts, they cause insect bites. Other insects that may invoke lesions by using their mouthparts are fleas, bugs and lice. Insects may bite to access food sources or to defend themselves.

On the other hand, evolution brought forward a wide variety of insects that dispose of specialized organs to inject venom into the body of a potential enemy, e.g., the sting of bees and wasps. These organs are usually supported by an insect's abdomen. Although insect bite and insect sting are often used interchangeably, they are clearly different entities from a zoological point of view. Of note, some species, like wasps may bite and sting. Most humans who encounter wasps are stung, not bitten, though.

Some insect bites are associated with papule formation, transient pruritus and/or localized pain, others are not even noticed by the person who got bitten [1]. However, certain patient groups have high risks of severe, possibly lethal complications. These patient groups comprise people who present hypersensitivity reactions after exposure to insect allergens as well as immunocompromised patients who may develop local reactions or systemic symptoms.

Insects constitute a huge class of animals that comprises several millions of species. In general, an insect's body consists of head, thorax and abdomen, whereby three pairs of legs can be observed on the thorax. Indeed, the fact that insects have six legs and arachnids have eight may be used to distinguish animals pertaining to either one taxonomic class.

The insect's head carries antennae, primitive eyes and mouthparts. Evolution brought forward a wide variety of species whose mouthparts are adapted to pierce human (or other species') skin and to suck blood. From a zoological point of view, this is an insect bite. Considering that definition, mosquitos, fleas, bugs and lice bite.

In contrast, other insects have a sting which is typically located towards the rear end of the animal and which has evolved to inject venom into the body of a possible enemy. These insects sting. While there is a clear difference between an insect bite and an insect sting, some species - wasps, for instance - may bite and sting.

In most cases, insect bites are minor nuisances that cause urticaria and pruritus, symptoms that usually subside within a few hours or days. However, biting insects may also transmit serious diseases, e.g., malaria, leishmaniasis and Chagas disease. Thus, prevention of insect bites does not only aim at avoiding formation of itchy papules but is of major importance for anyone living in or traveling to geographical regions where the aforementioned diseases are endemic.

Severe adverse reactions to insect bites are rarely observed. Immunodeficient individuals may present with tissue necrosis due to an insect bite. Other patients may suffer an allergic reaction and develop life-threatening anaphylaxis, though insect stings are much more likely to induce anaphylaxis than insect bites.

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