Understanding Mystery Bug Bites

Bedbug bites

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Mystery bugs are a common phenomenon known to pest control professionals, doctors, office managers, airline flight attendants, movie and restaurant staff, and hotel managers. The scenario goes like this: A homeowner or customer feels as though they've been bitten by a bug (or many bugs), but close inspection can find no insect to blame. The victim may even have raised welts or spots that seem to prove they've been bitten, but no insect can be found, no matter how thorough the search.

The Real Mystery Bugs

There are, of course, many tiny insects that can bite you. It is certainly possible (and all-too common) that tiny bedbugs can infest spaces and escape detection. At only about 1/5 inch in size, bedbugs often are overlooked—especially since the itchy reaction to the bite may not begin until several days after the bite.

A chigger, a type of mite, is only about 1/120-inch long—virtually microscopic—and produces a bite that elicits an allergic reaction that can last for as much as two weeks. The aptly named no-see-um (1/25 inch) can also escape your notice. Even the considerably large flea, at up to 1/8 inch, can be overlooked after it nips you.

Some tiny bugs that bite include:

These pests, however, have a characteristic bite, and a doctor will generally be able to identify the insect and make an educated guess as to where and how you were bitten. But there are also many, many instances of bug bites that have no known cause.

The Other Mystery Bugs

Many mystery bites, itches, and bumps are traced to environmental factors—or even psychological causes—rather than actual insects.

Mystery bugs or mystery bites are, in fact, very common. Pest control professionals are often called into businesses or homes because people believe they are being bitten, but they don't see any bugs, and entire offices or families will come down with symptoms even though no insects can be found. Thus, because the true source can be a mystery to all involved, these phenomena are known as mystery bugs and bites.

Environmental, Physiological, and Psychological Bites

Among the many possible causes of mystery bites:

  • Dry air and static electricity: A lack of humidity in the air can cause the skin to become dry and itchy, and that dryness and irritation can be aggravated by static electricity. Try using a humidifier to get more moisture in the air.
  • Carpet or paper fibers: Fibers from synthetic carpeting or splinter-like fibers from paper can get on the skin and cause bite-like sores or itching. This is generally a temporary condition, but vacuuming more often may help.
  • Allergies: Whether it be an allergy to an animal, plant, pollen, or food, common allergic symptoms include rashes and itchy skin. See your doctor for diagnosis and treatment. Such allergies can also cause hives, which are easily mistaken for bug bites
  • Soaps and detergents: If you recently switched laundry detergent or body soap, your body may react to an ingredient in the new product. Try switching to another brand, or, better yet, go back to your old one that didn't irritate.
  • Prescription drugs: Starting on a new medication, overusing a medication, or being on one longer than recommended can all cause physical reactions, which could be rashes, bumps or itches similar to what one would expect of a bug bite. See your doctor for diagnosis and treatment.
  • Diseases and medical conditions: Many health-related factors can cause rash-like symptoms that are irritating or itching. Such problems should be diagnosed and/or treated by a medical doctor.
  • Stress: Similar to medical conditions, stress can cause a person to break out in a rash or hives. In extreme cases, stress can lead to even more severe issues, such as delusory parasitosis—the perception that bugs, insects, or worms are crawling over or into one's skin and biting. A doctor should be consulted if the condition persists.
  • Power of suggestion: Just like yawning, the very act of one person scratching an itch can cause others to feel itchy themselves. Even talking or reading about itchy skin can give one the urge to scratch.