About Insect Stings: Causes

There are three types or groups of poisonous stinging insects commonly found in North America:

  • the hymenoptera - honeybees and bumblebees
  • the vespids - wasps, hornets, and yellow jackets
  • fire ants - a wingless type of insect found only in the southeastern U.S.

All three types have different kinds of venom, but none is likely to be dangerous in small doses unless someone is sensitive and allergic to the poison.

There are also dozens of species of biting and bloodsucking ticks, blackflies, sand flies, deerflies, horseflies, mosquitoes, bedbugs, and fleas. None of them are technically poisonous, but some have saliva that can irritate or provoke a reaction, and others can introduce infections when they bite. The best-known example of this is Lyme disease, caused by the bite of a deer tick that carries a parasite capable of causing disease in humans.

Other ticks of the same family may cause a temporary spreading paralysis if they go undiscovered for a few days. These creatures hang on and suck blood over as long as four days, becoming fatter in the process. After about two days, some species start producing new chemicals in their saliva, which can temporarily shut down parts of the human nervous system. This is called tick paralysis, and it's quite different from Lyme disease. It clears up after the tick is removed, but can potentially be fatal if breathing stops.

Mites that make their living around humans, such as house dust mites, don't bite, but there are bird and animal mites that occasionally attack humans and leave larvae (chiggers) in the skin. These cause local skin reactions in both allergic and non-allergic people. Chiggers cause redness and itching (pruritic dermatitis), while adult mites leave a small bite that usually becomes irritated hours or days later. You're most likely to be bitten by a mite if you handle live birds or poultry, pigs, rabbits, cats and dogs (especially puppies), seeds, straw or hay.

Learn more about First Aid