How to Handle Parasitosis

Pest management professionals often get calls from people claiming to have been bitten or stung by unknown bugs.

But on occasion, even after conducting thorough site inspections and multiple service visits, no evidence of such pests can be found.

Numerous things can cause skin irritations that are similar to insect bites and stings. These include allergies to laundry detergents, fragments of fiberglass insulation, fungi, mould and plants with thorns, stinging hairs or toxic sap, among others. 

And sometimes the customer doesn’t actually have pests but rather is suffering from a serious mental health issue such as delusory parasitosis, Ekbom’s Syndrome or monosymptomatic hypochondriasis. These are medical conditions where the afflicted person believes he or she is infested by things that bite, crawl or burrow into the skin.

According to Dr. Gerry Wegner, retired technical director of Varment Guard Environmental Services (now a Plunkett’s Pest Control company) who wrote about psychoses in PCT’s Guide to Commercial Pest Management (2014), these people are “absolutely convinced that they are infested with minute insects, mites or worms when, in fact, no such organisms are present.”

A similar illness, delusory cleptoparasitosis, is when a person believes his or her home or belongings are infested (and remain infested) by tiny or microscopic parasitic organisms despite evidence to the contrary.

Unfortunately, the COVID-19 pandemic has been particularly hard on people’s mental health. Between April 2019 and April 2021, the United Kingdom saw a 29 per cent increase in the number of people referred to mental health services for their first suspected episode of psychosis, according to data from the National Health Service.

“It’s probably similar here. We’re seeing huge increases in depression and anxiety, which can in their extreme forms cause some psychosis,” says Dr. Christine Korol, director of the Vancouver Anxiety Centre and an adjunct professor of psychology at the University of British Columbia. For people who are genetically predisposed to schizophrenia or bipolar disorder, situations of extreme stress like we’ve experienced also can tip the scale and cause a first episode of psychosis, she says.

Some pest management professionals say they have experienced more instances of clients being bothered by imaginary pests.

Billy Martin, owner of Martin’s Pest Control in Calgary, recently had a customer claim that bugs were all over his bed, but these bugs disappeared when he flipped his bed sheets in the air. Inspection and monitoring using traps failed to find evidence of a target pest. “In Canada, you need a target pest” to apply chemical controls, reminds Martin.

Another customer claimed bugs were biting him in the shower and was very unhappy to hear that Martin could not apply pesticide to the shower or while the customer was in the shower.

When faced with ‘mystery bite’ situations in homes and offices, Wegner suggests the following:

Get signed approval before proceeding. Investigating these situations takes time and incurs costs, whether you find actual pests or not. So before proceeding with the investigation, provide a written quotation for signed approval. Besides the service fee, the quote might outline the investigation’s scope and timeframe.

Ask good questions. As at any initial service call, interview the person who claims to have been bitten, stung, infested or infected. Ask qualifying questions: Have you seen what is biting you? Where and when in the home is this taking place? Has the residence or building had any rodent, bird or wildlife issues recently?

Stay in your lane. Do not ask medically diagnostic questions or attempt to perform examinations on the person for bites or stings. Do, however, look for other sources that could be irritating the client’s skin. (Wegner provides a list of these in PCT’s Guide to Commercial Pest Management.)

Inspect thoroughly. Inspect the premises both indoors and out and where the alleged bites are occurring. Wear personal protective equipment, such as disposable rubber gloves. Collect specimens, including those provided by the client, for identification by an entomologist.

Don’t reach for pesticide. In Canada, a pesticide cannot legally be applied without proper identification of the target labeled pest. Pesticide application should never be considered a default course of action, reminds Wegner.

Monitor closely. If the inspection does not yield evidence of pest activity, set out monitors and traps (pheromone, glue, etc.) where the client says bites have occurred. Place them along walls and underneath furniture and beds. In office settings, put them in desks and on desktops behind computers, phones and files. After one to two weeks, collect the devices and any additional specimens collected by the client.

Allay anxiety through communication. Explain how specimens will be evaluated by an entomologist and make arrangements to call the client or communicate in writing the findings of the investigation.

Document everything. From the client’s initial inquiry through every step of the investigation, take detailed notes and photos.

Never assume. “Do not prematurely dismiss the mystery bites or sensations as delusory parasitosis if no evidence of biting arthropods is found by you or a coworker,” writes Wegner. Instead, tactfully and respectfully suggest that an industrial or home-environment hygienist or medical professional may be able to provide a solution to the bite sensations.

Korol adds: If you’re concerned about a person who lives alone, some provinces will perform a wellness check.

The author is a frequent contributor to PCT.