Stings and bites from insects are common. They often result in redness and swelling in the injured area. Sometimes a sting or bite can cause a life-threatening allergic reaction or transmit pathogens (viruses, bacteria or parasites) to humans.
Insect Bites Causes

Most insects do not usually attack humans unless they are provoked. Most insects sting to protect their hives or nests or when incidentally touched or disturbed.

Bites or stings from bees, wasps, hornets, yellow jackets, and fire ants may cause serious reactions in people who are allergic to them. Death from bee stings is 3 to 4 times more common than death from snake bites.

Bees, wasps, and fire ants differ in how they inflict injury. When a bee stings, it loses its entire stinger and actually dies in the process. A wasp can inflict multiple stings because it does not lose its stinger after it stings. Fire ants inject their venom by using their mandibles (the biting parts of their jaw) and rotating their bodies. They may inject venom many times. Puss caterpillars (or asp) have hollow “hairs” or spines that break when touched and toxin is injected into the skin.

Some insects not only sting or bite, but can also carry and spread serious and deadly diseases:
• Mosquitoes – Malaria, West Nile Virus, Dengue, Yellow Fever
• Lice – Epidemic relapsing fever
• Sand fly – Leishmaniasis
• Deer fly – Tularemia
• Tsetse flies – Sleeping sickness
• Fleas – Bubonic plague
• Ticks – Lyme disease and others
Other arachnids (bugs) such as chiggers, bedbugs, and mites typically cause self-limited localized itchiness and occasional swelling. Serious bites from spiders (arachnids), which are not insects, can be from the black widow or brown recluse spiders. In unsanitary conditions the common housefly can play a role in the spread of human intestinal infections.
Insect Bites Symptoms
The response to a sting or bite from insects depends on a variety of factors. Most bites and stings result in pain, swelling, redness, and itching to the affected area and some may even blister. The skin may be broken and become infected. If not treated properly, these local infections may become severe and cause other serious medical conditions.
You may also experience an allergic reaction to the sting that can be serious, or even life threatening.

When to Seek Medical Care

If you start to experience symptoms that are not just at the site of the bite or sting, seek medical attention. These symptoms may progress to fatal anaphylactic shock. If the bite appears infected see a doctor. Call your doctor if there is an open wound, which may suggest a poisonous spider bite.

People who have a history of severe reactions should go to the nearest hospital’s emergency department after a bite or sting if they experience any symptoms. Those who have no history of severe reactions should also go to the emergency department if they have any of the following symptoms:
• Wheezing
• Chest tightness or pain
• Sensation of the throat closing or difficulty speaking or swallowing
• Infection
• Difficulty breathing
• Swelling of the lips, eyelids or throat
• Dizziness, faintness or confusion
• Rapid heartbeat
• Hives
• Nausea, cramps or vomiting
• A scorpion sting and in a child
Insect Bites Treatment

Treatment depends on the type of reaction. Severe reactions are treated with injections of epinephrine and an antihistamine. Steroids are sometimes prescribed. Oral antibiotics may also be given for infected bite wounds.

Prevention

You can minimize your exposure to insect bites by following some of these suggestions:
• Avoid outdoor activity during the twilight periods at dawn and dusk or in the evening if there are mosquitoes in the area.
• Wear long-sleeved shirts, long pants, and hats to minimize the areas of exposed skin. Shirts should be tucked in.
• Use insect repellants.
Usually, the signs and symptoms of a bite or sting disappear in a day or two. If you’re concerned — even if your reaction is minor — call your doctor.