Health Articles

Human parasites

Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory
June 2008
Arthropod Diagnostician Extension Entomology Specialist What You Should Know
• Very few insects are considered pests, and even fewer are actual y parasites of humans. • If you believe your body is infested with insects or other parasites, consult a physician immediately. • Never try to remove parasites or treat yourself.
Entomologists often get "bug" samples for identification, including those that accidental y infest residences. In the United States, we are Fig. 1. Typical specimens collected by delusions of fortunate to have very few arthropods (e.g., insects, cleptoparasitosis sufferer. Glass contains rubbing alcohol, spiders, mites, ticks, etc.) that actual y infest or feed on pieces of fiber, crumbs, sticks, and various particles. The humans. Rarely, samples come from the human body, client was convinced there were arthropods in this glass.1 most often fleas, lice and mites. Table 1 lists the most common arthropods in North America that can infest Steps for Diagnosing Human Parasites
or feed on humans. In addition, only a few arthropods infest and cause damage to structures, and include: If you believe that your body has been infested with carpenter ants, termites, powderpost beetles, carpet parasites, or your residence is infested structural pests, beetles, and clothes moths. the following steps should be taken to determine a proper diagnosis. In general, always use a professional to properly identify the pest and make management Table 1. Most common North American human parasites
recommendations for long-term control. Common Name Scientific Name If you believe your body is infested: human body louse Pediculus humanus humanus human • Visit your family physician or dermatologist for a Pediculus humanus capitus complete check-up.
Pthirus pubis Cimex lectularius • If recommended, have the doctor take skin sam- Cimex pilosellus ples of suspected infested area. DO NOT take skin Haematosiphon inodorus samples yourself, because it could lead to personal Oeciacus vicarius injury and/or contamination of the sample.
Triatominae species Oriental rat flea Xenopsylla cheopis • If a parasite is confirmed by the doctor, talk openly Pulex irritans about possible treatments. If arthropods are not Ctenocephalides canis detected, be open-minded about other causes.
Ctenocephalides felis chigoe; sandflea Tunga penetrans scabies; itch mite Sarcoptes scabiei If you believe your residence is infested: Notoedres cati • Have the pest(s) positively identified by an ento- Dermanyssus gallinae mologist or another professional BEFORE you make tropical rat mite Ornithonyssus bacoti treatment decisions. Pyemotes tritici Dermacentor species • Consult an entomologist on ways to prevent reinfes- Xodes species tation and long-term control.
Amblyomma americanum • If an arthropod or infestation can't be found, con- Rhipicehpalus sanguineus sider alternate causes for structural damage. UPPDL, 5305 Old Main Hill, Logan UT 84322-5305 T: 435.797.2435 F: 435.797.8197 Negative Diagnosis: Now What?
Delusions of Parasitosis
Sometimes doctors, dermatologists and entomologists If you are certain that you are infested with bugs, but find no causal agent behind your bodily or residential doctors and entomologists do not agree with you, there arthropod infestation, but you are stil afflicted with the are other possibilities of the origins of your infestation. symptomology of infestation. If you are not satisfied A delusion is defined as a fixed belief that is held to be with a diagnosis it is always advisable to seek a second true despite evidence to the contrary (for example, you opinion; however, second opinions may result in the believe you are infested, but doctors and entomologists same diagnosis. If you enter a cycle where you seek out say you are not). The problem is that your symptoms are new doctors, contact new entomologists and/or submit real, but you believe the cause is one thing (arthropods) many samples that never yield desired diagnoses, call when in reality it might be caused by something many pest-control companies to inspect and/or spray else (medication interactions or side effects, il ness, insecticides, or have attempted self-treatment, you must psychological disorders, traumatic experiences in your consider other causes for your infestation. Other causal past, stress, or even guilt). Please refer to Table 2 to see agents commonly misdiagnosed as parasitic infestations the broad range of medical conditions that may cause include environmental, medical, or psychological sensations like inflammation of the skin (dermatitis), problems. Below is a brief discussion of non-arthropod abnormal redness of the skin (erythema), sensations of causes for symptoms of bodily or home infestation.
bugs crawling on the skin (formication), sensations of prickling, tingling or creeping on the skin (paresthesia), Entomophobia is defined as a persistent, excessive and
itching (pruritus) and wound or cut marks from scratching irrational fear of insects. (urticaria). The sensation of parasites could be from a non-arthropod source. Illusions of Parasitosis2 when the symptomology of a
person's believed infestation is environmental. Examples
of this include fiberglass or other fibers that cause
Table 2. Common medical conditions and side effects3
itching, direct air-flow to some part of the body causing drying and itching, and al ergens/detergents in the erythema paresthesia pruritus rash urticaria house that cause rashes. Commonly, this type of il usion is shared by many people (up to 150 in one account) sharing close quarters (common at home or work) who are al convinced that they are infested. For il usions of autoimmune disease parasitosis, simply modifying the environmental problem may resolve the suspected arthropod infestation. Since this type of il usion is usual y fixable, it wil not be covered in any more detail in this fact sheet. If arthropods are not found in your home or any of your submitted samples, environmental factors should be ruled out before diabetes mellitus pursuing further treatment. fluoride poisoning heavy metal toxicity Delusions of Parasitosis when people believe they are
being bitten or infested by arthropods, but no parasites are present. If this is a possibillity there are ways to treat your symptoms so that you may return to living a pest- Delusions of Cleptoparasitosis4 not as common as
delusions of parasitosis. This occurs when people believe that their house or belongings are infested with multiple sclerosis arthropods (Fig. 1). Symptoms, causes and treatments of delusions of cleptoparasitosis are similar to delusions of rheumatoid arthritis UPPDL, 5305 Old Main Hill, Logan UT 84322-5305 T: 435.797.2435 F: 435.797.8197 Delusions of Parasitosis Continued
Sometimes medical conditions alone do not cause parasitosis-like symptoms. For some people, prescription and non-prescription drugs, like cocaine or methamphetamines, can cause irritating dermatological symptoms. Occasional y, people may be taking multiple medications that cause negative interactions. Table 3. Forty-nine most commonly prescribed medications in the United States and their side effects3
Drug Type erythema paresthesia pruritus rash urticaria Hydrocodone/APAP Darvocet, Darvon Propoxyphene N/APAP Tylenol with Codeine Acetaminophen/Codeine analgesic Prednisone, Panasol Trimeth/Sulfameth Trimox, Augmentin Albuterol, Ventolin Triamterene/HCTZ cardiovascular - Premarin, Prempro Furosemide, Lasix Procardia, Adalat Tenormin, Atenolol Zestril, Prinivil Synthroid, Levoxyl UPPDL, 5305 Old Main Hill, Logan UT 84322-5305 T: 435.797.2435 F: 435.797.8197 Delusions of Parasitosis Continued
environmental causes. It is important that we recognize delusions of parasitosis symptoms in order to better help those individuals. People with delusions of parasitosis If you do not take any medications, nor have any serious often fail to provide actual specimens, but can provide medical issues listed above, then the problem may be of vivid and detailed descriptions of their pests: a psychological origin. If all options have already been examined, and the cycle of doctors, entomologists, and • black and white, but change colors pest control companies continues without end, it is highly recommended that a psychologist be seen. There are • have eight little legs and a small sucker many underlying issues like depression, dementia, anxiety, • half moon shape, like the end of a fingernail and stress that can lead to delusions of parasitosis. • moth-like creatures With therapy, and treating the underlying problems, full • waxy looking fuzz balls recovery can be attained. There are also prescription • granules about the size of a grain of salt medications available which can alleviate your • long hairs that move independently symptoms. A candid visit to your psychologist, in most • tiny white worm with a brown bob on its head cases, will lead to treatment and recovery. • worm-like coating around the hair root, with a black bulb attached Human Parasites For Entomologists
Although not as common, sometimes the delusion can An entomologist's role is to positively identify arthropods manifest itself in the form of a household infestation found in and around human structures and property, instead of on the body, called delusions of cleptoparasi- and make management recommendations when tosis. Some common attributes of delusions necessary. If human or animal parasites (e.g., fleas, lice, of cleptoparasatosis sufferers are listed below. etc.) are detected, a physician or veterinarian should be consulted for treatment. Entomologists or other • strong conviction of home arthropod infestation, but professional inspectors are not allowed to diagnose none are present medical conditions, even if those conditions directly • emotional trauma, especially from marital problems or indirectly involve arthropods. Sometimes, samples • submit samples of fiber, cloth, hairs, scabs as possible simply do not contain any arthropods, and therefore identification is impossible. Furthermore, no action • have multiple home inspections examining arthropod- can be recommended except to seek the advise of damaged wood, but damage is normal wear-and-tear a qualified physician. Sometimes the entomologists' • multiple phone calls or office visits which usually diagnosis, positive or negative, is not agreed with by the escalate in hostility as a desired diagnosis is not client. This is especially true for an apparently on-going parasitic infestation with no supporting evidence. • sufferers are usually older individuals, especially females • symptomology is similar to, or may progress to those As entomologists, we can only examine samples and commonly seen in delusions of parasitosis identify the presence or absence of arthropods. We are • client suddenly breaks-off communication not qualified to make other suggestions for medical or 1 Image courtesy of Erin Hodgson, Utah State University Extension.
2 Willliam Waldron. 1972. The Entomologist and Illusions of Parasitosis. The Western Journal of Medicine. Vol. 117 No. 2, pp. 76-78.
3 Tables were recreated from "Delusory Parasitosis" with permission from Nancy C. Hinkle. American Entomologist, Vol. 46 No. 1, pp. 17-25.
4 Kenneth J. Grace and David L. Wood. 1987. Delusory Cleptoparasitosis: Delusions of Arthropod Infestation in the Home. Pan-Pacific Entomologist, Vol. 63 No. 1, pp. 1-4.
Precautionary Statement: Al pesticides have benefits and risks, however fol owing the label wil maximize the benefits and reduce risks. Pay attention to the
directions for use and fol ow precautionary statements. Pesticide labels are considered legal documents containing instructions and limitations. Inconsistent
use of the product or disregarding the label is a violation of both federal and state laws. The pesticide applicator is legally responsible for proper use.
Utah State University is committed to providing an environment free from harassment and other forms of il egal discrimination based on race, color, religion, sex, national origin, age (40 and older), disability, and veteran's status. USU's policy also prohibits discrimination on the basis of sexual orientation in employment and academic related practices and decisions. USU employees and students cannot, because of race, color, religion, sex, national origin, age, disability, or veteran's status, refuse to hire; discharge; promote; demote; ter-minate; discriminate in compensation; or discriminate regarding terms, privileges, or conditions of employment, against any person otherwise qualified. Employees and students also cannot discriminate in the classroom, residence hal s, or in on/off campus, USU-sponsored events and activities. This publication is issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Noelle Cockett, Vice President for Extension and Agriculture, Utah State University.

Source: http://extension.usu.edu/htm/publications/file=9062