Insect Bites Definition
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, for example) to humans.
Arthropods are insects that live primarily on land and have six legs. They dominate the present-day land fauna. They represent about three-fourths of known animal life. In fact, the actual number of living species is not known and is estimated to be over 10 million.
The orders that contain the greatest numbers of species are:
- Coleoptera (beetles),
- Lepidoptera (butterflies and moths),
- Hymenoptera (ants, bees, wasps), and
- Diptera (true flies).
However, the majority of people lump insects, arthropods, and anything small that bites or stings as a
"bug" or an insect. The goal of this article is to provide an overview of biting and stinging insects or bugs without making strict scientific definitions of insects or bugs. The article covers the predominant biting and stinging bugs seen or imported to the US recently, but does not cover every possible stinging or biting bug or insect worldwide.
Insect Bites causes
Most insects do not usually attack humans unless they are provoked. Many
bites and stings are defensive. Insects sting to protect their hives or nests or
when incidentally touched or disturbed (so hives and nests should not be
disturbed or approached).
A sting or bite injects venom composed of proteins and other substances that
may trigger an allergic reaction in the victim. The sting also causes redness
and swelling at the site of the sting.
Bees, wasps, hornets, yellow jackets, and fire ants are members of the
Hymenoptera family. Bites or stings from these species 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.
wasps, and fire ants differ in how they inflict injury.
- When a bee stings, it loses the entire injection apparatus (stinger) and
actually dies in the process.
- A wasp can inflict multiple stings because it does not lose its
injection apparatus 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 (Megalopyge opercularis or asp) have hollow
"hairs" or spines (setae) that break when touched and toxin is injected into
- In contrast, bites from mosquitoes are not defensive; mosquitoes are
looking to get blood for a meal. Typically, most mosquitoes do not cause
significant illnesses or allergic reactions unless they convey "vectors," or
pathogenic microorganisms that actually live within the mosquitoes. For
malaria is caused by an organism that spends part of its life
cycle in a particular species of mosquitoes. West Nile virus
disease spread by a mosquito. Various mosquitoes spread other viral diseases
(such as equine encephalitis;
dengue and yellow fever to humans and other
Other types of insects or bugs that bite for a blood meal and diseases that
are possibly transmitted are as follows:
Lice bites can transmit epidemic relapsing fever, caused by spirochetes
- Leishmaniasis, caused by the protozoan Leishmania, is carried by a sand
- Sleeping sickness in humans and a group of cattle diseases that are
widespread in Africa, and known as, are caused by protozoan
trypanosomes transmitted by the bites of tsetse flies.
- Bacteria-caused diseases tularemia can be spread by deer fly bites, the
bubonic plague by fleas, and the epidemic typhus rickettsia by lice.
- Ticks (arachnids) can transmit Lyme disease and several other illnesses
through their bites; ticks bite so they can obtain a blood meal.
- 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; the spiders bite usually as a
Other insects and bugs can transmit diseases by simply transferring pathogens
like Salmonella spp by contact. For example, in unsanitary conditions,
the common housefly can play an incidental role in the spread of human
intestinal infections (such as typhoid, bacillary and amebic dysentery) by
contamination of human food as it lands and "walks" over foods after
previously "walking" on contaminated items like feces.
Medically Reviewed by a Doctor on 7/7/2014
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