Mystery Bugs

Pinprick-like biting sensations, usually on exposed skin and often producing inflammations that resemble insect bites, can be a persistent problem in some buildings. Occupants tend to blame these "bites" on some sort of pest infestation, typically fleas (which are rare in schools or office buildings), or "paper mites" (which do not exist). Demands for spraying of the affected space are often carried out in the absence of any evidence that biting insects are present. In fact, "paper mites" are almost always tiny, irritating particles like paper shards that constitute a cleaning or indoor air pollution problem rather than a pest problem.

The Role of Management
The most common mistake of management in "paper mite" situations is to automatically request a pesticide treatment, thereby incurring liability in the event occupants experience adverse reactions to the chemical. The second most common mistake is for supervisors to dismiss the complaints of biting as imagination. Although there are cases where people imagine they are being attacked by unseen parasites, most instances of biting-like sensations in buildings involve a genuine source of skin irritation. The circumstances can be further complicated, because health care professionals unfamiliar with the "paper mite syndrome" frequently misdiagnose the resulting welts as insect bites. Other people may believe that microscopic dust mites are involved; dust mites are real, but they cause breathing distress rather than bites. Finally, it is normal for the coworkers of a person complaining about "paper mites" to develop a heightened sensitivity to their own skin irritations (many caused away from the workplace) through the "power of suggestion." Management must treat all concerned with sympathy and respect, at the same time emphasizing that no pesticide treatment can be authorized without positive confirmation that a pest problem exists.

 

Control and Management

Inspection for Parasites
An inspection of the affected area should be carried out by a pest control technician who understands that pests may not be involved. Usually when real parasites are present, many are present and are readily seen. The most common types in buildings are mites coming from bird nests or from rodent infestations. If a thorough investigation fails to produce any specimens, a non-pest cause is probably responsible. However, it is standard procedure to place sticky traps throughout the area as monitors. In addition, occupants should be instructed to capture anything they suspect is biting them on a piece of clear tape. If biting insects such as fleas are present, the area may need to be treated. However, the captured items are typically bits of debris or tiny, harmless insects that are usually present inside buildings as a result of inadequately filtered air intakes.

Inspection for Airborne Particles
When it is reasonably certain that there are no biting insects in the affected space, the pest control program is no longer involved. Only rarely are the specific culprits in "paper mite" cases positively determined, although there are often strong suspects. Shards of fiber glass insulation (such as from batting above drop ceilings), particles from both newly installed as well as worn carpet and carpet pads and paper dust from separating forms and computer printouts along tear-lines are some of the most common proven causes of pinprick-like irritations. The dry air of many workplaces not only makes skin more sensitive to these tiny splinters, it increases the static electricity that is responsible for the particles "jumping" onto exposed skin. (Sometimes the static-charged bits are mistaken for living bugs.) Any activity that stirs up accumulated dust, such as building remodeling, renovation or the purging of old files, often leads to a "paper mite" outbreak. In cases where there is no obvious explanation, or multiple factors are suspected, an industrial hygienist should be called in to investigate.

Corrective Action
Sometimes pesticide spraying or fogging brings temporary relief to occupants with a "paper mite" problem. Although part of the reason is psychological, the main reason is that the spray acts to settle the irritating particles and to decrease static in the room. Although it is questionable and misleading to use pesticides in this fashion, the same principle can be accomplished by other means. A program of frequent damp cleaning, including carpet washing with water only, is often an effective short-term response while efforts are made to identify and eliminate the source of the irritation. Cleaning by wiping rather than vacuuming is recommended, unless the vacuum is equipped with a HEPA (high-efficiency) filter, since more dust may become airborne as a result. Use of humidifiers or air purifiers can be of tremendous benefit if the affected space is not too extensive. It may be worthwhile for some employees to seek the advice of a dermatologist or other medical specialist, since simple skin treatments (such as the use of moisturizers and milder soaps) are frequently used to minimize problems with irritation.