Connecting the Dots: Causes Behind Mysterious Bites, Sensations of Bites, and Skin Disturbances 1

— This article by Jerry Cates was first published on 2 January 2017, and was last revised and expanded on 9 September 2022. © Bugsinthenews Vol. 19:01(01).

General Anatomy of Human Skin (Source: Note that the skin consists of three major layers: (1) the thin outer layer or epidermis, composed of five strata of skin cells that protect the body from microbial contamination and desiccation; followed by (2) the thicker middle layer, or dermis, that contains hair follicles and the muscles that control their movement, the sebaceous and sweat glands, the blood and lymph vessels, and the nerve endings that sense pain, touch, cold and heat; and finally, (3) the thickest layer underlying the other two, or hypodermis, which is composed mostly of fat cells.

Skin Lesions from Stealth Bites, Witnessed Bites, and Non-Bites…

Lots of different organisms bite humans, and much of the time their bites produce lesions on our skin. Sometimes the bites are witnessed, sometimes not. Most flea bites, and many bites caused by other organisms, are immediately felt at the time the bite event takes place. A flea bite, for example, is usually felt and the offending flea is usually seen where it is biting the skin. Later, when the bite wound itches, turns red, and produces a raised wheal, the bitten person normally remembers what caused the wound.

By comparison, many other organisms bite stealthily. The saliva and other secretions associated with the biting apparatus of bed bugs, some mosquitoes, certain mites including chiggers, and a host of other bloodsucking organisms are laced with anesthetizing agents. Those agents block signals from nerves and pressure/pain/injury detecting structures in the bitten person’s skin, and prevent alarm signals from reaching the brain. When a reddened, itchy bump pops up later on (chigger bite lesions, for example, typically do not show up until three days or more after exposure to them), only then does one become aware that the earlier bite event occurred. Then, the first thought that comes to most people is “What bit me?

The natural association between skin lesions and biting events is imprinted on our minds early in life, and is reinforced by a string of life experiences that accumulate as we pass from infancy into adulthood and beyond. Many children and most adults presume that any reddened, raised, itchy lesion found on their skin whose cause is not immediately obvious must have resulted from a “bite.” When such lesions occur, and we worry that more bites will come, our focus is on finding and eradicating the offending biter. So, we marshal whatever investigatory equipment is at hand, apply the cognitive thought processes we’ve developed at that stage in our lives, and — usually somewhere along the way — call out our pest management provider.

Often, despite our efforts and those of our exterminator, no biting organisms are found. Then, when our skin lesions grow more numerous and begin showing up on parts of our bodies that others can see, worry can turn to near-panic.

Typical Skin Surface, Elderly Male: Upper Wrist. Source: EntomoBiotics Inc. Archives.

Skin Lesions sans Bites…

Most of the time, if our skin lesions are — in fact — caused by biting organisms, we do not have to search long to find the culprit. Sometimes, however, even the most diligent of searches, conducted over lengthy periods of time, either fails to uncover the cause or identifies as the culprit an organism that stands wrongly accused.

Exterminating the Unknown?

Often, even when no specific organism can be found, an exterminator is called in to treat the home with a broad-band pesticide in hopes of eliminating an “unknown” organism that has somehow eluded discovery. In a surprising number of cases, the exterminator who is called in will actually perform such a treatment, with few or no clues about what they are supposed to be exterminating.

Exterminating Innocent Organisms?

Wrongly accusing an innocent organism, then acting on that accusation by using a pesticide to exterminate it, is also common. If the causal association is weak, and if the scientific literature does not support the association, wisdom mandates that the exterminator should proceed with great caution. If the two do not appear connected in any way save being found in the same home, extermination is contraindicated.

What Can Possibly Go Wrong With That?

But, one might ask, what particularly bad could come from applying broadband pesticides against an unknown organism, in hopes of wiping it out even if it can’t be found? Or exterminating an organism that was not causing the client’s misery? Actually, in many cases the negative consequences are significant. Often, for example, the sufferer soon experiences similar “bites,” suggesting the extermination had no effect whatsoever. At that point the sufferer’s stress rises to new levels. Sometimes, instead of improving the client’s plight, the extermination treatment appears to make things worse, and the sufferer’s stress rockets to new heights.

Choosing Between Two Possibilities…

Now the anxious sufferer is forced to choose between two possibilities: either the real cause is a yet-unknown biting organism that is amazingly adept at hiding its presence, or the sufferer’s skin lesions are not bites at all. Skin lesions can result from immune or dermatological reactions to foreign or irritating materials and/or chemicals. Others can be produced by chemical changes within our bodies. A wide range of combinations of all these causes — biting organisms, immune reactions, irritants, and a changing endocrine system — can be present at once.

It is healthy — even crucial — for humans to shrug off minor, isolated, and infrequent skin lesions that do not persist, or that do not directly impact one’s life. Transitory bumps, sores, and rashes are the natural result of living in a diverse ecosystem. But, when multiple skin wounds of unknown cause suddenly show up on a person’s body, worry can turn to outright, urgent concern, even for those with high thresholds of pain. That concern usually leads the affected person on a diligent, even obsessive, search for the cause behind it. Aiding such individuals in conducting a worthwhile search for answers is the object of this article. We begin by considering a few of the usual cause and effect relationships.

Precipitating Events and Chronic Skin Disturbances…

Although skin lesions are experienced as three-dimensional phenomena, the fourth dimension — time — plays important roles that are easily overlooked. Complicating, time-related issues can arise from several sources. We will examine one of those in what follows below, and others later in this paper. When one considers the bewildering combinations of the myriad possibilities that can act together, it is no wonder that we sometimes find it difficult to know the exact cause behind an individual’s acute and chronic skin disturbances.

Typical Underbed Detritus. magnified 400x. This material consists mostly of synthetic and natural textile fibers, but includes microscopic dust particles of plastic, metallic, and wood chips. Source: EntomoBiotics Inc. Archives.

Once worrisome skin lesions are discovered, the sufferer’s immediate reaction impacts the feel and appearance of those lesions later. In most cases, that reaction follows a predictable path bolstered by popular, successful advertising campaigns conducted by some of the world’s largest corporations.

In 1935, E. I. du Pont de Nemours and Company adopted as its company motto the phrase “Better Things for Better Living…Through Chemistry.” The company continued using this slogan in its advertising until 1982, when the “Through Chemistry” suffix was abandoned. In 1999, Dupont adopted “The miracles of science” as its flagship slogan, which remains in use today. Other chemical companies, including those manufacturing soaps and skin-related cosmetic and soothing agents, took to using the phrase “Better Living Through Chemistry” not long after DuPont’s original slogan was coined. That phrase continues to be used extensively today, and — as proof of its popularity — has even been the title of a hit record album (1996) and a film (2014).

The successful touting of chemical products, peddled and hawked unceasingly by respected corporate giants, as “The Solution” to all the skin problems we humans experience in life, has brought relief from itches, scrapes, and rashes to millions, and filled the coffers of the companies that make and sell the stuff that produces such relief. But relief is not always the result, especially when those products are used for lengthy periods of time. Applying salves, lotions, emollients, and sprays advertised to soothe, reduce, or cure skin eruptions, infections, rashes, and irritations can — and often do — cause more skin problems than they solve. More often, those resulting problems take on a life of their own, producing skin issues that have nothing to do with the original lesions, but which the sufferer may think come from the same cause.

A similar picture emerges when pesticides and repellents — even those derived from natural, organic plant-based botanical sources — are applied, misted, or sprayed in a home, workplace, or recreation setting. Such chemicals, though used strictly to ameliorate, mitigate, or prevent real or suspected infestations of biting organisms, also affect the humans exposed to them. That exposure often leads to skin problems in persons who live, work, or play where the pesticides and repellents are used.

One of the first questions the author asks, when called to investigate the cause of a sufferer’s “bites”, is what they are applying to their skin to sooth the itch and pain, and what they have used to kill the bugs they think are responsible for those “bites.” Much of the time the sufferer replies with a long list of products. They include, for example, antibacterial soaps and shampoos, over-the-counter antibiotics, lotions with impossible-to-read ingredient lists, and a raft of over-the-counter pesticides and repellents. The next question? “How long have you been using that stuff?” Typically, the product use began shortly after the skin lesions commenced, and continue to the present. On hearing this, the author gently suggests the client might consider avoiding everything on that list, immediately, unless they have been prescribed by a licensed medical professional. Some of the sufferers who take this advice report an immediate improvement in their skin condition. In a few cases, their skin lesions resolve completely, often in short order.

The author has not, at this time, been able to conduct a scientific tally of the frequency of such improvements, or whether the improvements ultimately resolved the sufferer’s skin lesions entirely on a regular basis. In the interest of objectivity, more research must be conducted.

Mysterious Bites, Sensations of Bites, and Skin Disturbances

As previously stated, this article is about bites, sensations of bites, and skin disturbances affecting humans for which no immediately discernible cause is evident. They are mysterious because no definite cause is at hand, or because — despite suspicions about the possible or likely cause — scientific evidence is lacking.

The focus of this article, then, must cover at least three related but separate inquiries:

First, we will examine those mysterious bites that occur with regularity, but for which no clear cause is obvious.

Next, we will discuss mysterious skin lesions that often accompany such bites or that occur by themselves, again with regularity, without the accompanying sensation of a bite, but for which — again — no definite cause can be identified.

Finally, we will broaden the scope of inquiry into the causes of such mysterious lesions and sensations, including a wide range of inorganic ones. We are led to do this because, although most of those who suffer from these mysterious events automatically presume the cause to be a biting organism of some kind, in a number of important cases organisms that bite, parasitize, or otherwise harm our bodies are not involved.

Keep in mind that this article is in a state of constant evolution. This is a complex topic, one with multiple dimensions that are not easily examined in as objective and clinical a manner as would be preferred. Still, objectivity is the author’s primary focus. The reader’s comments, criticisms, and recommendations are eagerly solicited…

Life’s Natural, Usually Invisible Detritus…

Often, in each of the broad categories of skin-related mysteries described above, a number of tantalizing possible causes are evident. These mostly include previously unnoticed white, brown, red or black specks, lines or threads or tubular objects that may appear as worm-like organisms, or minuscule fuzzy objects that appear as eggs or biological larvae to the naked eye.

Sometimes this evidence turns out, on close examination, to be what the sufferer thinks it is. More often, though, it is revealed, under the microscope, to be nothing more than a sampling of the undifferentiated debris that typifies our natural surroundings. This natural detritus, though always present but not usually noticed, offers a false hope to the sufferer that proof of a definite cause is readily at hand.

A microscopic analysis of this detritus, studied via a crisp, well-focused image of the material under investigation, proves it to consist of a collection of skin flakes, plastic chips, fragments of the normal insect or arachnid body parts common to most homes, segments of pet and human hair, cotton, nylon, polyester, and other manufactured threads, and compact clumps of textile fibers. Some of these articles are usually even embedded in tiny quantities of hardened mucus and other bodily fluids such as lymph, plasma, and blood, in such a way as to make them appear as legs emerging from an organic body of some kind. Mother nature does have a sense of humor. Or, perhaps, we should blame the fact that our natural visual acuity won’t allow us to discern, with the unaided eye, what a good, laboratory grade microscope makes plain and obvious.

It might also be said, however, that nothing good can come from conducting a thorough, microscopic examination of the places where one lives, works, and plays. Why? Because the examination will undoubtably produce a whole host of tiny stuff that — particularly when the investigatory instruments are of poor quality or are operated by one inexperienced in their proper use — may mistakenly be thought as the source of what is making one’s life miserable.

A bird mite collected from a bathroom fixture in a nursing facility in Round Rock, Texas. The fixture was positioned directly beneath a vent whose exhaust tube was clogged with nesting materials deposited by birds over the previous ten to fifteen years. Mites migrated from the nest to the ventilator cover. When the fan was turned on the assembled mites were blown down, onto whomever was sitting on the commode. Source: EntomoBiotics Inc. archives.

The fact is, being inundated with microscopic detritus, shed by us and other humans, our pets, our clothing, furniture, even our electrical and electronic gadgetry, is and has been a fact of life. Not only is this true in the modern world, but it has been the case since time began. The average human, for example, sheds many ounces of skin flakes every year, and those skin flakes get distributed throughout all the places where we and other humans live, work, and play.

Cave dwellers living thousands of years ago were no different in this regard from we humans of the 21st century. Analyses of the herbs and spices that cave dwellers, eons ago, often lined their sleeping mats with — most likely in an effort to ameliorate the conditions which were causing them discomforts of various kinds — provide tantalizing evidence of that.

Carpeting, furniture, clothing, and other sources of textile fibers — common, but prized articles of the modern world, though roughly analogous to the fibrous sleeping mats of our cave-dwelling forebears — produce quantities of lint rivaling in weight and volume that of human skin flakes. Unlike skin flakes, however, that lint easily floats in the air and coats exposed surfaces inside our homes.

Try running your finger along the upper surfaces of the picture frames in your living room to see how much of this “stuff” has been floating around, then consider that the same “stuff” not only lights on your picture frames, but also lands on your exposed skin as you meander through life. Some of it sticks, particularly to skin that is oily, sore, or irritated and weeping. Some of what sticks may later be pulled off your skin, and can easily, yet mistakenly, be thought to have emerged therefrom…

Microscopic plastic and metallic chips left over from the manufacture of our electronic and electrical gadgets also contribute to the detritus that gets scattered throughout the places in which we live, play, and work. When only that and nothing that might be termed “the usual biological suspects” is detected in the course of a thorough microscopic analysis of the detritus collected in such places, the sufferer doesn’t know what to think. Again, that bugaboo known as confirmation bias can come into play here, and lead you to unwarranted conclusions. We’ll get to that later on in this paper.

The Usual Biological Suspects

Springtail (Seira bipunctata). Collected in a residence in northwest Austin, Texas. Springtails are sub-microscopic, and some species are coated with microscopic scales that irritate the skin of susceptible individuals. Source: EntomoBiotics Inc. archives.

When the cause of a bite or skin lesion is not immediately obvious, the list of possibilities that comes to mind, or that is revealed in the process of an Internet search, is deceptively short. Bed bugs and mites top the list, followed by fleas, lice, kissing bugs, mosquitoes, no-see-ums, thrips, springtails, spiders, and irritating hairs shed by carpet beetle larvae.

Mature bed bug, from a home in Pflugerville, Texas. Source: EntomoBiotics Inc. archives.

But that’s not the full story. Mites, for example, are represented by a long list of acarid families, genera, and species with remarkably different habits. Tiny springtails are a common inhabitant of many of the ecosystems humans occupy; species diversity is enormous, and though some springtail species possess morphological features such as scales that may irritate human skin, many do not. Though many investigators doubt that springtails are legitimate sources of dermatological lesions, Altschuler (2004) reported finding springtails and fragments of them in skin scrapings from 18 of 20 individuals reporting symptoms of stinging/biting and/or crawling, who had previously diagnosed with delusory parasitosis.

Despite the daunting complexity, however, all of these suspects have one thing in common. A careful investigation by an experienced investigator practically always results in identifying either the causal organism or the presence of conditions conducive to the presence of specific causal organisms that are the most likely culprits.

A rodent mite, one of several species collected from the floor of an Austin, Texas residence, that had migrated from an abandoned rat’s nest underneath the home. The resident was being bitten by the mites, whose bites produced angry red wheals on his skin that could have been misdiagnosed as bed bug bites. Source: EntomoBiotics Inc. archives.

Such investigations are difficult to carry out, and amateurish attempts to do so often lead sufferers astray. Cheap microscopes that produce blurry images, for example, easily turn plain plastic chips and skin flakes into “tiny animals with legs.”

Triatomid kissing bug. Collected at a rural home near Copeland, Texas. These bugs were hiding in the baseboards of the home’s master bedroom, and coming out at night to suck blood from the husband and wife who slept there. Source: EntomoBiotics Inc. archives.

It is common for an investigator in this field of study to receive images of suspicious objects thought by those suffering from skin lesions to be the cause of their sufferings. Those images, arriving via email, embedded in text messages, and as photos displayed on cellular phones, tablets, and computer screens, are typically of poor quality (though improvements in smart-phone cameras, operated by individuals with steady hands, have of late been a great help). A slightly out-of-focus object that, under the person’s personal microscope or magnifying glass, seems to have six to eight hairy legs, can and often does lead the sufferer astray.

Poor images are unacceptably problematic, because distinguishing between a legitimate biting organism and something else requires imagery that resolves critical morphological features. To obtain such imagery, the investigator must take the actual specimen provided by the client, place it on the stage of a laboratory-grade microscope — preferably a portable instrument that can be brought directly to the client’s location — and thus render the object’s actual form in sharp focus on a  high-resolution computer screen that allows both the investigator and the client to clearly see what the microscope reveals. If the object resolves as a known biting organism, voila! An answer that can be dealt with has been found. Much of the time, that’s what happens, and the results are satisfying.

Often, though, when viewed in sharp focus on the computer screen, the “legs” that were so obvious under poor magnification disappear and the object is exposed as an inert piece of detritus. Just as often, the next ten or fifteen specimens supplied by the client also turn out to be inert, lifeless fragments of undifferentiated debris.

When this happens, the results are anything but satisfying, though — typically — the client recognizes and accepts the truth displayed by the microscope, at least for the specimens that have thus far been examined. So, how many more need to be examined? That’s a good question, one the investigator must struggle with. For many clients, the answer is “Until you find something that confirms my belief.” We’ll discuss confirmation bias later in this article, as it does figure into the best way to answer the question at hand. Still, objectivity demands that all involved in the investigation maintain open minds and avoid coming to hasty conclusions.

The best approach, for the unbiased investigator, is to continue examining as many of the client’s specimens as time permits. Often, though, the investigator ends up placing what seems an endless stream of specimens under the microscope, displaying them on a computer screen for the client to see, without finding a single biting organism, yet the sufferer remains unconvinced. For that reason it makes sense to prepare prospective clients beforehand by asking how they will react if, on microscopic examination of their specimens, no biting organisms can be found. If they answer “I could never accept that!” it is best that the investigation not commence until the client is receptive to a more realistic approach. Many skin lesions are the result of causes other than biting organisms, and the client needs to be ready to accept that. Moving forward in a productive, healthy way, to explore those other causes and determine if one or more of those other causes figures in a particular client’s predicament, is a critical element in finding a solution that works.

Skin Lesions From Causes Other than Biting Organisms…

Some skin lesions are caused by organisms that do not bite. In some cases the lesions result from reactions to the organism’s scales, hairs, and/or secretions. The most common examples are allergic reactions to cats, dogs, and other pets, reactions to the microscopic hairs (hastisetae) shed by carpet beetle larvae, the microscopic scales shed by springtails, and the fecal droppings produced by cockroaches and other insects. We will discuss several of those in what follows.

In many other cases, however, skin lesions emanate from causes that have nothing to do with biological organisms of any kind, living or dead. To discuss these examples, we must venture briefly into the fields of human physiology, neurology, and endocrinology, which are more properly the purview of medical doctors, physiologists, nutritionists, and similar specialists. Accordingly, my comments here — none of which should be taken as a substitute for advice from a medical professional — will be purposely limited. Those comments are interspersed throughout what follows, and are summarized in the last few paragraphs of this paper, under the heading “Additional Food for Thought…“.

Professional Forensic Inspections…

A proper investigation into the causes of a sufferer’s symptoms includes inspecting the premises where the person or persons suffering bites or skin lesions lives, works, or plays. It also involves documenting, step-by-step, the events leading to the start of the bites or skin lesions. The investigator must be trained and experienced in entomology, acarology, and arachnology, and equipped with appropriate, laboratory-grade instruments and collection accessories.

Carpet beetle larva (approx. 2mm long) collected from a home in south Austin. Texas. The robust hairs (spicasetae) do not cause irritation, but microscopic hairs (hastisetae, shown in figs. 506 & 507) concentrated at the larva’s posterior and scattered on its body can be highly irritating to susceptible individuals. Source: EntomoBiotics Inc. archives.

Further, the investigator must have high-quality dissecting instruments, uncontaminated specimen collection vials, microscope slides and fixing media, and the accessories related to them, close at hand.

Microscopic hastisetae from the larva of a carpet beetle collected in Lakeway, Texas. The spearpoint tips of the hairs easily get caught in the interstitial spaces between skin cells, then progress deeper into the skin with time. The barbed shafts of the hairs are arranged like tiny umbrellas, such that they point away from the hair tip. Because of this, as the hairs sink deeper into the skin, the tiny umbrella-like structures are forced open, contaminating the wound path with any debris they contain. Since, in those with intact immune systems, infectious pathogens would immediately be attacked and neutralized, contact with hastisetae and their contaminants rarely leads to the production of noticeable lesions or even minor irritation. Stressed individuals, however, with compromised immune systems, are unable to mount the immediate immune response needed to  prevent pathogens from proliferating, though secondary immune responses usually nullify them before long. Thus, small, localized infections often are experienced by such individuals, and may produce skin lesions mimicking bed bug bites. Most individuals who are affected by carpet beetle hastisetae are undergoing unusual levels of stress. Source: EntomoBiotics Inc. archives.

The search for “silver bullet” remedies never ceases, there are at present no known shortcuts to this process. Determining, via objective investigation and careful documentation what is and is not causing a sufferer’s skin lesions is a crucial first step toward bringing them to a halt. Ineffectually guessing about the cause, while the sufferer experiments with an endless stream of remedies — many of which may worsen the sufferer’s skin condition — wastes precious time and resources.

The author has published a separate article entitled “What’s Biting You?” that describes the usual biological suspects in some detail. Please refer to that paper for detailed information on those organisms.

Carpet beetle hastisetae and spicasetae. Note the hastisetae can be quite long, while the more robust spicasetae, which do not irritate the skin, are shorter and have projecting structures that make it difficult to penetrate and progress deep into human skin. The photographs in figs. 506 and 507 were taken through a digital microscope, at the EntomoBiotics Lab, that magnified the hastisetae 750-1000x. Source: EntomoBiotics Inc. archives.

When Forensic Investigations Fail to Detect a Cause…

Forensic inspections alone don’t always succeed in finding a cause. The investigator is not acting as a medical professional and therefore is, by definition, searching for an indirect cause that is external to the sufferer. When a direct cause is involved, one internal to the sufferer, the inspection fails.

As mentioned earlier, this article is about causes behind mysterious bites, sensations of bites, and lesions that even well-conducted forensic investigations often cannot easily detect. Dealing with a witnessed bite, an event caused by an organism that is observed in an act that leads to a skin lesion or another human malady, and with any of the “usual biological suspects” that a forensic investigation detects, is generally uncomplicated.

Not only do doctors and nurses know how to treat such bites and lesions, but experienced pest management personnel use similar information to devise rational extermination, mitigation, and prevention programs that stop the biting and skin disturbances emanating from them.

But what happens when the cause cannot be identified even after a supposedly thorough investigation has been carried out?

Diagram of the Epidermis (Source:, showing the five strata of cells that make up the outer skin. Note that this diagram is an elucidation of the uppermost layer of the three layers comprising human skin as previously diagrammed in Fig. 1. The uppermost layer of the stratum corneum, shown here as the dark, thin layer at the top of the diagram, is the outer skin. It is this layer that is constantly shed as we live our lives. The average human sheds their outermost layer of epidermis at the rate of 0.001 – 0.003 ounces of skin flakes every hour, roughly 0.024 – 0.072 ounces per day, or 9-27oz/year, which translates to 0.55 – 1.6 pounds of dead skin per year, per person. 

If the bites soon stop and the skin lesions go away quickly, nothing happens. Life goes on, and the bites or the skin lesions are forgotten. Most of us experience a multitude of such “road-bump” events throughout our lives. We roll with the punches, brush ourselves off, and continue undaunted down the path of life on which we presently tread.

On the other hand, what if the bites continue, the skin lesions worsen, and/or more skin lesions develop? Then the sufferer’s life is turned upside down as he or she is subjected to an on-going, arduous, frustrating experience that for most is costly, harrowing, emotionally draining, and physiologically damaging.

The author is often brought in to investigate such cases, usually after months or years have passed since the bites and/or skin lesions commenced. Sometimes the sufferer has been informed by physicians and others in authority that their problem is purely psychological. In other cases they have concluded, have been told by trusted acquaintances, or have found what appears to be authoritative information on the Internet that their suffering is caused by new classes of organisms that scientists don’t yet know about.

Blood Brain Barrier. Source: Stolp HB, Liddelow SA, Sá-Pereira I, Dziegielewska KM and Saunders NR (2013) Immune responses at brain barriers and implications for brain development and neurological function in later life. Front. Integr. Neurosci. 7:61. doi: 10.3389/fnint.2013.00061. Four main interfaces separate the central nervous system and the periphery. (1) the blood-brain barrier proper; (2) the blood-CSF barrier; (3) the outer CSF-brain barrier and the level of the pia arachnoid; and (4) the inner CSF-brain barrier, present only in early development (not present in the adult).

Though it is folly to absolutely rule out the existence of new classes of organisms we have yet to discover, it is just as foolish to ascribe to such organisms the suffering caused by bites and skin lesions of unknown etiology. The fact is, a multitude of possible and likely causes of such suffering is known. Many of those transcend simple interactions between the sufferer and the environment. Even if the cause is not purely psychological, it can be caused, and exacerbated, by unexpected and misinterpreted interactions between a number of natural anatomical structures within the sufferer’s body. The author describes those structures and their interactions later in this article.

Sadly, many of these sufferings could have been brought to a halt early on, had the sufferer and the sufferer’s advisors understood the underlying cause or causes involved. Some, however, are not amenable to the simple resolutions that surround the identification and eradication of limited, specific causes. Multiple causations that interact to present a confusing picture are often involved. In a few of these cases, the cause actually is one or more live biological organisms that previous investigations overlooked. In others, though live biological organisms are implicated, it is not they but the remnants they leave behind after molting or dying, that become problematic. In yet other cases, even though live or remnants of dead organisms may have been involved at the onset, those causes had been resolved earlier, but the continuation of the sufferer’s problems results strictly from the remedies the sufferer or his/her advisors employ in a misguided campaign to bring the bites and lesions to a halt.

Delusory Parasitosis (DP) and Ekbom Syndrome (ES)…

Norepinephrine (from Greek roots meaning “at or alongside the kidneys”): an organic chemical in the catecholamine family, functioning as a hormone and neurotransmitter in the brain and body.

Beyond causes stemming from interactions with actual organisms of one kind or another, in some cases the sufferer is delusional. Such sufferers are victims of what researchers like Nancy Hinkle, PhD, refer to as Delusory Parasitosis. Originally known as “Delusions of Parasitosis,” the term was shortened to its present form by W. G. Waldron in 1962, and is today often described simply by the initials “DP” or by the medical definition known as Ekbom Syndrome (ES). Hinkle has more recently (2010) published a paper on “Ekbom Syndrome: The Challenge of ‘Invisible Bug’ Infestations.


Here we will refer to this malady as DP/ES, but the reader is cautioned against drawing hasty conclusions from what is presented. It is important to point out, before exploring this topic in more detail, that diagnosing DP/ES is a difficult process, and this article is not intended as a guide to such diagnoses. As Hinkle points out, the medical community considers the incidence of DP/ES to be somewhat rare, yet pest control personnel and entomologists encounter clients suffering from what they (including, from all indications, researchers like Nancy Hinkle) assume to be cases of DP/ES on a regular basis. The implication of this disparity is that many suspected cases of DP/ES are misdiagnosed. This author’s own investigatory work bears that out.

Wolfgang Trabert (1995) estimated that at the time he was conducting research on DP/ES there were about 25,000 DP/ES sufferers in the United States. Considering that the U.S. population in 1995 stood at 262,764,948, the incidence rate estimated by Trabert was in the neighborhood of 95 individuals out of every 1 million. Thus, assuming that figure still holds, we could surmise that in a metropolitan area the size of Austin, Texas (calculated as including  Bastrop, Caldwell, Hays, Travis, and Williamson Counties, with a combined total population in 2013 estimated at 2,000,860), we would expect to find — at least in 2013 — about 190 DP/ES sufferers. For one reason or another, many of those with DP/ES will not seek treatment or other forms of professional remediation for their condition. If as many as 10% do, the number of such individuals encountered by pest management personnel would be close to 20.

This author has met a number of individuals who — to one degree or another — fit the mold of the DP/ES sufferer. Some have all the symptoms, but others present with only one or a few. For those with the least number of signs of DP/ES, rational intervention and a sympathetic, informed approach often works wonders, but an unsympathetic, impatient investigator who cannot or will not comprehend what the sufferer is going through, and who is unable to explain to the sufferer how their symptoms may point away from parasitic causes, can do more harm than good.

DP/ES and Recreational Drug Abuse


Many recreational drugs have been known to produce DP/ES in those who abuse them. Methamphetamine, in particular, is known to be associated with the condition. Significant research has been conducted into the association between methamphetamine abuse and DP/ES over the past four decades, to the point that, today, physiologists have a relatively well-developed understanding of the etiology and progression of the associative relationship between them. That relationship, and similar ones that result in outright psychoses, has figured significantly in world history.


Famous cases of amphetamine addiction and less than sane behavior include Nazi Germany’s Adolf Hitler. That tragic figure was a vegetarian tee-totaler who, besides shunning alcohol, refused to drink coffee because of its supposed toxic nature, and was said to not even touch women. Despite this long list of what he considered to be rational, ethically-based restrictions on some of the most significant facets of his life, Hitler had himself injected, almost daily, with methamphetamine by his personal physician, Dr. Theodor Morell. The injections began as early as 1942, and continued afterward until his death in 1945.

Germany has, historically, nurtured more than its share of pharmacologists. In the early decades of the last century that nation was not just a leading exporter of opiates, including morphine and cocaine, but held a near-worldwide monopoly on the drugs. In 1937 methamphetamine-hydrochloride, later manufactured in pill form and branded and marketed as Pervitin, was patented by Dr. Fritz Hauschild, the head chemist at Temmler Werke GmbH, Berlin. Factory workers were recommended to take Pervetin, in pill and confectionary forms (e.g., Hildebrand chocolates), throughout the day as a means staying awake and getting more work done. College students, doctors, and others seeking to shed the shackles of normal life — “shackles” such as sleep, which today is regarded as a prerequisite to maintaining one’s physiological and psychological health — happily accepted that methamphetamine would give them superhuman stamina and concentration. Soon even the German military “recognized” the “value” of methamphetamine as a means of attenuating anxiety, increasing concentration, and maintaining courage in battle.

The German experiment with methamphetamine during WW-II proved that it does all those things, but only for a time. Then it turns on its users and makes their lives a living hell.


Methamphetamine does one thing well, and a bunch of other things badly: it is unusually capable of passing through the blood-brain barrier where it induces an increase in norephenephrine and serotonin levels in the brain. Thus it elevates mood, making the user euphoric, but at a high cost. Unlike amphetamine, it is neurotoxic, and at high doses induces psychosis, seizures and brain hemorrhages.

Amphetamine has one methyl group, and is known as methylated phenylethylamine. Methamphetamine, with two methyl groups, is known as double methylated phenylethylamine. Methyl groups reduce the polarity of a molecule, and the more methyl groups, the less polar a molecule is the more hydrophobic and lipophilic it becomes. Amphetamine, with one methyl group, is somewhat lipophilic, and is able to slowly permeate the blood-brain barrier; methamphetamine, with two methyl groups, is highly lipophilic, and crosses the blood-brain barrier quickly.


Once inside the brain, methamphetamine retains its molecular structure much longer than amphetamine, producing euphoric effects with a duration several times that of the latter. Then, when it is metabolized, it first is stripped of its extra methyl group, and turns into amphetamine. The user, in the extended euphoric state that methamphetamine induces, can stay awake up to seven or more days at a time. But sleep is necessary for the brain to retain its hold on reality, and it should come as no surprise that methamphetamine abusers often begin to experience hallucinations in which they sense bugs crawling on their skin.

Earlier, above, we briefly touched upon the postulated, but unlikely, existence of organisms science has yet to discover. What about chemicals that mimic neurotransmitters in the brain, chemicals that exist only for short periods of time but are able, in that short time, to produce the sensation of crawling bugs, on the skin? We have only touched the surface of understanding where brain chemistry is concerned in this regard…

The Curious Case of J. R. Traver…

Perhaps the most storied of alleged DP/ES victims was J. R. Traver, a zoologist at the University of Massachusetts, Amherst. In 1951 Traver published a treatise on her research into a mite, which she identified taxonomically as Dermatophagoides scheremetewskyi Bogdanov (sometimes, as in Traver’s treatise, Bogdanov is spelled Bogdanow, but because most references use the former spelling it shall be used here), that she claimed had been infesting her body for the past 17 years.

And thereby hangs a tale…

A tale that, in fact, presented scientists of the day with a perplexing question of monumental import. For most, the answer to that question is now fully settled: Traver was, pure and simple, a victim of DP/ES. To a small number of others, however, DP/ES is either not a full answer, or is no answer at all. This investigator confesses to be caught between these two extremes. To explain why, it is first necessary to provide some important background information.

The genus Dermatophagoides is, as biological genera go, a poorly known genus of cosmopolitan pyroglyphid (i.e, that cause eczema, a rash — pyro = fire — on the skin) house dust mites that live in human habitations. Dust mites feed on organic detritus. They are particularly fond of flakes of shed human skin, and because the average human sheds from 0.5-1.75 grams of skin daily (0.4-1.41 pounds of shed skin annually), occupied human dwellings provide considerable nutriment for them. They flourish in the stable environment of human-occupied homes and, though they perform a service by scavenging spent human skin, they are considered pests because of their causal relationship with asthma and allergies.

This causal relationship stems from the potent digestive chemicals in the house mite’s intestinal tract. These chemicals consist of specialized protease enzymes that enable the mites to break down the proteins composing the human skin flakes they ingest. Inasmuch as they persist in the mite’s feces and contaminate its exoskeleton, these enzymes, when inhaled with ordinary dust particles, naturally begin to break down the proteins composing the mucosa and other cellular structures of the respiratory tracts of the inhaler. As the inhaler’s respiratory tract come under attack, an immune response ensues that produces allergic reactions, including excessive production of mucus, a flooding of the affected area with excessive blood and lymph flows, and others.

The European house dust mite (Dermatophagoides pteronyssinus) and the American house dust mite (Dermatophagoides farinae) are two different species, but are not necessarily confined to Europe or North America. A third species, Euroglyphus maynei, is also widely distributed. Unlike scabies mites or skin follicle mites, none of the species in the genus Dermatophagoides, or in the genus Euroglyphus, is known to burrow under the skin or to thrive within the human body. Thus these house mites have never been confirmed, from a scientific point of view, as parasitic, though Traver claimed that a species in the genus Dermatophagoides parasitized her body and the bodies of two of her close relatives.

The species Traver described, Dermatophagoides scheremetewskyi Bogdanov, is rarely mentioned in today’s scientific literature. It was first reported in 1864 by Bogdanov, in a paper in which he also first described the genus Dermatophagoides. The species D. scheremetewskyi is mentioned cryptically in a number of scattered scientific papers published worldwide since Traver published her treatise and, according to the Global Biodiversity Information Facility (GBIF), it is today considered to be a valid species. However, a number of investigators, including Matthew J. Colloff’ in his 2009 treatise “Dust Mites,” infer the strong possibility that it is synonymous with D. pteronyssinus. In the 1975 edition (and in the 1978 revision) of Walter Ebeling’s authoritative handbook on urban entomology, D. scheremetewskyi was reported as a legitimate pest of humans:

“The problem of the person really having pests is, of course, generally much easier to solve than the problem of the person who has no pests but believes he has. An example of how obscure a real pest problem can be is illustrated by a report by J. R. Traver (1951) on an infestation of mites, Dermatophagoides scheremetewskyi Bogdanov, on her own person, resulting in itching red papules on scalp, eyes, ears, nostrils, shoulders, under the arms, beneath the breasts, on the chest, both upper and lower back, and occasionally around the umbilicus. Other members of her family were likewise infested. The ailment was initially diagnosed by a physician as ”psychoneurotic.” Fortunately, the victim was a zoologist, had access to a microscope, and found the causative agent. Many attempted treatments failed to eradicate the infestation. However, attacks by the implicated mite species are extremely rare.” Source: Ebeling, Walter, 1975. Urban Entomology. University of California, Riverside.

J. R. Traver died in 1974, having never succeeded in curing or ameliorating the self-identified infestation of these mites with which she claimed to be afflicted. Traver’s 1951 treatise has been the subject of numerous studies, positive and negative, including one that was particularly negative, published in 2011 by Matan Shelomi, entitled “Mad Scientist: The Unique Case of a Published Delusion.” Shelomi’s paper builds a case for retraction of Traver’s 1951 treatise based on the generally accepted conclusion that, in Shelomi’s own words, Traver’s “conclusions may be based on data that was unconsciously fabricated by the author’s mind. The paper may merit retraction on the grounds of error or even scientific misconduct ‘by reason of insanity,’ but such a retraction raises the issue of discrimination against the mentally ill.” Note, however, that even Shelomi could not state with certainty that Traver was the victim of a self-induced hoax.

Was Traver suffering from DP/ES? To this author the jury is still out, though the weight of the evidence available today is heavy in favor of that diagnosis. The author has nothing but the highest regard for Nancy Hinkle, and finds her research, which seems to suggest that Traver was such a victim, to be persuasive. Still, some doubt remains, scant though it may be. Both of Hinkle’s papers on DP/ES, which are linked to above, are highly recommended reading by anyone who is suffering from bites and skin lesions of unknown etiology, as well as by physicians treating such individuals, and by pest management professionals who are servicing the homes, places of work and recreation used by such individuals.

It is instructive to acknowledge the difficulties we in America face, today, when attempting to pursue a genuinely objective investigation of Traver’s condition. One impediment is the fact that, when she first concluded she was infested by the dust mite she identified, air conditioning was not available in most homes. For that reason, dust mites were much more prevalent then than now. Dust mites require a relative humidity above 65-70% to thrive, and in most modern air conditioned homes the relative humidity falls considerably below that figure all year long. For that reason, dust mites of all species are, in modern American homes, a rarity today.

The questionable treatise by J. R. Traver, also linked to above, may be instructive for yet another reason: if, as Hinkle, Shelomi, and a host of others authoritatively assert, Traver was suffering from DP/ES, her treatise provides insight into the mind of the DP/ES sufferer. Traver was highly educated. She was also capable of articulating her ironclad convictions so persuasively to physicians, entomologists, and others in academia and the medical community, that few of those she sought out for help could or would diagnose her condition as anything other than that which she, herself, had concluded it to be.

However — and, to this author, this is the most crucial point of all — besides her condition itself, Traver also describes in great detail the methods, procedures, and medications (including a list of clearly dangerous pesticides and drugs known to produce secondary physiological and neurological conditions) that she used to treat that condition. Whether her condition commenced with an infestation by the cited mite, or from the emanations of a troubled mind, those descriptions provide strong evidence pointing away from biological causes for the continuation of her skin conditions. Instead they point toward a variety of possible non-biological causes for them, DP/ES being but one of several.

Objectivity: Avoiding Confirmation Bias…

Charles Dickens illustrated confirmation bias in his novel, David Copperfield, in the person of the fictional character Uriah Heep. Heep, one of the main antagonists in the novel, made frequent references to his own ‘umbleness, and displayed what has been described aptly as a cloying humility. He was demonstrably insincere, attentive and obedient to the point of servility, and today his name is synonymous with being a sycophant (a bootlicker who flatters powerful people to secure their approval). The above ink and wash drawing was made by the British illustrator Fred Barnard, in the 1870’s. It is now in the public domain, in its country of origin and in other countries and areas where the copyright term is the author’s life plus 100 years or less.

This author discovered the power of the written word while very young, and as a child read with great interest how, in times past, scientists of antiquity were reviled for thinking and proposing ideas contrary to the accepted norm. Galileo was one of those, and he suffered greatly for his heretical views, views that later were found scientifically correct.

In every age new ideas that go against the grain are treated much as were those of Galileo, and today is no different. Centuries from now scientists of the future will look back on the “scholarly” work we have done and smirk with contempt. We know so little. But like those who came before, we delude ourselves into thinking we have most of “it” figured out. Yes, delusions do not discriminate, but afflict even the best among us (including even you and me), and the chief instrument of our delusory state is what is known as confirmation bias.

Confirmation bias describes the tendency to search for, interpret, favor, and recall information in a way that confirms one’s preexisting beliefs or hypotheses. Rather than weigh all the evidence equally (which would be the objective thing to do), we give disproportionately less consideration to alternative possibilities. Those suffering from confirmation bias are generally unconscious practitioners of systematic errors of inductive reasoning, and the malady is not limited to a few but is widespread in today’s culture, just as it was widespread in the cultures of history. For example, people display this bias when they collect or remember information selectively, or when they interpret that information in a biased way.

The effect is more pronounced when emotionally charged issues and deeply entrenched beliefs are involved, and is particularly evident when interpretations of ambiguous evidence — which, from an objective standpoint, should be examined with a jaundiced eye — are introduced without caveat in support of existing positions. Examples include situations in which attitudes become polarized, so that disagreements become more extreme even though the different parties are exposed to the same evidence. Beliefs can persevere even after the evidence for them is shown to be false. It is common for investigators to irrationally assign a greater relevance to information that is encountered early in the research project, and less relevance to that encountered later. Analysts are strangely prone to perceive associations between two events or situations when, on objective analysis, no such association exists.

Experiments in the 1960s confirmed the tendency, within even the most hallowed halls of academia, to conduct research in a way that confirmed existing beliefs and norms. It is folly to ignore this clear and well-documented tendency to test ideas in a one-sided way that focuses on a singular possibility while ignoring the alternatives, yet it is deceptively easy to fall into that trap. We are speaking here of the curious way the human mind works, and how what may appear to be firm conclusions are strongly, though often unconsciously, biased by preconceptions.

The reasons why this happens are varied, but perhaps the most important stems from the tendency for researchers to give more weight to the societal costs of being “wrong,” i.e., being thought as such, whether in actuality or not, than to the objective costs of investigating in a neutral, scientific way and, in the process, possibly producing results contrary to those being obtained by others, particularly others held in high esteem. In other words, nobody wants to be embarrassed within their scientific community, and the easiest way to avoid embarrassment is to go along with prevailing opinions, even if one has to spin the data under examination in the process.

What is not factored in, of course, is the cost that confirmation biases incur on the pace of scientific progress. Some beliefs are so closely held as to make their holders refuse to consider alternatives. Such attitudes contribute to overconfidence, leading even otherwise serious scientists to maintain or strengthen those beliefs despite being confronted with a mountain of contrary evidence.

This explains why the author is reluctant to arrive at firm conclusions on anything that remains yet in question, even if the questions appear to be on shaky ground. Hinkle rightly points out, in both her papers cited above, that even when many of the signs and symptoms of DP/ES are present, there may be genuine non-psychological causes involved. She then goes on to say that, even when psychological issues impinge, they may not be the only issues, nor the most important ones. It is incumbent on the investigator to conduct a thorough and objective analysis of every case. Unfortunately, such analyses are time-consuming and require the use of expensive investigatory instruments, and few field entomologists, and even fewer pest managers are sufficiently equipped, have the time required, or even the inclination needed, to invest in such projects.

Why Bites and Skin Lesions are so Discomfiting…

The mere sensation of a “bite,” even if the sensation is brief and slight and the immediate cause of the sensation cannot be discerned, is naturally upsetting to most sentient human beings. Similarly, discovering a disturbed area on the skin, especially upon awakening from sleep or on removing an article of clothing, is alarming.

We typically react to such experiences with varying degrees of emotion, trepidation, and genuine concern. We do so because past experiences and our grasp of the wealth of scientific knowledge at our fingertips tells us the “bite” we felt or the disturbed area on our skin we’ve found is likely not the end of it.

Oh, maybe we’ll go for days without another “bite.” Maybe the bump, wheal, or rash we’ve found will disappear within minutes, or hours, or a few days without leading to something worse. Or maybe not. There may be more to come. Maybe a lot more. And, yes, some of the possibilities are, to say the least, ugly.

We typically interpret a “bite” to mean that we have been attacked by a foreign organism. We know that most environments are loaded with a broad range of biters of one kind or another. We also know, from experience or from perusing the media du jour, that most of those biters are fitted with a minuscule but gruesome apparatus capable of injecting bad stuff into our bodies.

Really bad stuff…

How bad? Well, stuff like venom, viruses, bacteria, and parasites. Some of that bad stuff can, in fact, kill people. Others can produce virulent diseases that can lead to an early grave, and chronic ones lasting a long, tortuous lifetime. Between those extremes and “nothing to worry about” lies a huge gulf, and even when near the “nothing to worry about” side, practically all that bad stuff still makes life less pleasant. Therefore, one naturally reasons, it would be foolish not to recognize the risks that come with bites and skin disturbances.

The Human Skin and How It Recognizes Pressure, Touch, Heat, Cold, and Pain…

The largest internal organ in the human body is the liver (unless one views largeness in terms of surface area rather than volume, and considers the gastrointestinal tract to be an internal organ). But this article isn’t about internal organs, so we will leave discussions on the liver to others. Our interest is in the body’s largest organ over all, which happens to be the skin, particularly if you consider the gastrointestinal tract an extension of the skin. The human skin, particularly that portion which covers our outer body, is the organ we use to interact, immediately and directly, with the outside world. The world outside our body tells us about itself by touching us, and our skin uses that touch, from the outside world, to communicate to our brain the nature of the outside world with which we are in direct contact. It does so by activating a number of specialized sensors: Meissner’s corpuscles, Pacinian corpuscles, Merkel disks, and Ruffini endings.

Meissner’s and Pacinian corpuscles adapt rapidly, and quickly stop firing in response to a constant stimulus. Merkel disks and Ruffini endings, on the other hand, adapt slowly and do not stop firing as long as a stimulus is present. A pencil held in one hand will cause the holder’s Meissner’s corpuscles, Pacinian corpuscles, Merkel’s disks, and Ruffini’s endings to fire the moment it is picked up. If the pen is held still, though, the Meissner’s and Pacinian corpuscles immediately stop firing, while the Merkel’s disks and Ruffini endings will continue to fire as long as the pencil is held.

Pain and temperature sensing does not require the use of specialized nerve receptors. Instead, free nerve endings throughout skin, muscle, bone, and connective tissue manage to perceive changes in temperature and pain peptides indirectly. Although the sensation of pain results whenever a free nerve ending is damaged, the sensation of pain mostly results when certain substances are released by damaged tissues. Free nerve endings have receptors for these substances, which include prostaglandins, histamine, and substance P. When those receptors are activated the free nerve endings signal the brain that the affected tissue has been damaged.

Free Nerve Endings

Fig. 1100. Details of Skin Structure (Source: unknown) showing major sensory organs in the various skin layers.

In figure 3 (click on the image to get a larger view of it) we see a diagram of the sensory organs within the skin that allow us to discern the nature of the outside world impinging upon us at any given time. One of the most important of these sensory organs is a scattering of free nerve ends.

Free nerve endings, which happen to be the most common type of nerve endings in the body, resemble the fine roots of plants. They penetrate the dermis layer of the skin, and terminate in the stratum granulosum. They are able to detect temperature, touch, pressure, stretch, or pain.

Root Hair Plexus, and Arrector Pili Muscle

Fig. 1101. Free Nerve Endings (Source: staff. “Blausen gallery 2014”).

One very important group of free nerve endings in the human skin forms a plexus (from a Latin root meaning “braid”; in human anatomy the term refers to a branching network of vessels or nerves, and  as used here refers specifically to a network of nerve axons in the skin) around our skin’s hair follicles. Each root hair plexus forms a network around the hair follicle, and sends and receives nerve impulses to and from the brain when the hair moves.

Notice that another structure, located in the same area and attached to each hair, is a muscle known as the arrector pili. Each arrector pili muscle is composed of a bundle of smooth muscle fibers that attach to several hair follicles at once. The hair follicles attached to a given arrector pili muscle are known as a follicular unit; each arrector pili muscle is innervated by the sympathetic branch of the autonomic nervous system.

The autonomic nervous system is involuntary. We don’t consciously control how it operates. Instead, it gets its instructions from the portion of the brain known as the hypothalamus, which controls a host of body organs (like the beating of our hearts, and the contraction and relaxation of our diaphragms) and keeps us going without the need of conscious action on our part.

When, for example, stresses such as cold air are sensed by the root hair plexus, the hypothalamus tells the arrector pili to contract. The hairs to which the contracting arrector pili is attached then become erect, giving us what we call “goose bumps,” conveniently trapping the air closest to the skin so that body heat is conserved. But coldness is not the only thing that causes the arrector pili to contract. Fear produces the same result, and the reaction, being involuntary, takes place unexpectedly.

Imagine the huge number of arrector pili muscles in the skin, all being managed and instructed, individually, by the hypothalamus. Like any computer, the sensory inputs to the hypothalamus can become overwhelmed, particularly when the body is under unusual levels of stress. One result can be that part of the autonomic nervous system won’t know what other parts of the system are doing.

Whenever the arrector pili contracts, other sensitive nerve endings nearby — nerve endings that are not associated with the arrector pili but that are associated with the huge number of root hair plexuses — report back to the brain that the hair has moved. If, when this happens, the brain is so preoccupied by other stressors that it cannot associate the two events in a direct cause-and-effect relationship, the result may be a “feeling” that something foreign is crawling on the skin.

Meissner’s (Tactile) Corpuscles

Meissner’s Corpuscle. (Source: Drawn by Henry Vandyke Carter, now in public domain). Papilla of the hand. Magnified 350 times.
A. Side view of a papilla of the hand.
a. Cortical layer.
b. Tactile corpuscle.
c. Small nerve of the papilla, with neurolemma.
d. Its two nervous fibers running with spiral coils around the tactile corpuscle.
e. Apparent termination of one of these fibers.
B. A tactile papilla seen from above so as to show its transverse section.
a. Cortical layer.
b. Nerve fiber.
c. Outer layer of the tactile body, with nuclei.
d. Clear interior substance.

The root hair plexus isn’t the only sensory organ in the skin that can fool the brain into thinking something external to a person’s body has intruded when the source of the stimulus is within the body itself. Meissner’s (tactile) corpuscles, Pacinian (lamellar) corpuscles, Merkel’s disks or cells, and Ruffini endings (also known as Ruffini Corpuscles or Bulbous Corpuscles) also are capable of psychophysical tomfoolery of one kind or another.

Meissner’s corpuscle is a relatively large sensory organ found scattered over our bodies. It is a highly adaptive nerve ending that senses light touch, and has its highest sensitivity when exposed to vibrations between 10 and 50 Hertz. Arrays of Meissner’s corpuscles are most concentrated in thick, hairless skin, in areas especially sensitive to light touch, such as the fingers and lips, just beneath the epidermis within the dermal papillae.

Physiologically they are encapsulated unmyelinated nerve endings, made up of flattened supportive cells, arranged as horizontal lamellae surrounded by a connective tissue capsule. Neurologically they are sensitive to shape and textural changes in exploratory and discriminatory touch. They can only signal that something is touching the skin.

Pacinian (lamellar) Corpuscles

Pacinian (Lamellar) Corpuscle. (Source: Henry Vandyke Carter – Henry Gray (1918) Anatomy of the Human Body; Gray’s Anatomy, Plate 935; now in public domain)

Pacinian, also known as lamellar, corpuscles are larger and fewer in number than Meissner’s corpuscles, rapidly adapt to change, and are especially sensitivity to vibration (optimally those at 250 Hz, ) and pressure. They respond to sudden disturbances, particularly the rhythmic variety. They detect surface texture and enable the brain to sense pressure changes.

Physiologically, Pacinian corpuscles are oval cylinders some 1 mm long, fully wrapped in connective tissue; the interiors of each corpuscle are arranged into 20 to 60 concentric page-shapped lamellae, with each “page” comprising an axon membrane that is separated from the adjacent membranes by a gelatinous insulator. Neurologically, each corpuscle is sensitive to being deformed, whereupon pressure-sensitive sodium ion channels in the axon membranes are opened that, on leaking sufficient sodium ions, causes the corpuscle to “fire,” or transmit, a receptor signal to the brain. The transmitted signal is not binary, but analog, in that the frequency of transmitted impulses from the corpuscle indicates the severity of the potentiating deformity.

Merkel’s disks (Merkel nerve endings, or Merkel cells)

Merkel’s Disks (Source: Anatomy & Physiology, Connexions Web).

Merkel’s disks, cells, or nerve endings (as they are variously described in the scientific literature) are large, myelinated nerve endings that reside in the basal epidermis and hair follicles. They are mechanorecepters that, unlike Meissner’s and Pacinian corpuscles, adapt slowly to stimuli. In human physiology, they provide the brain with information relating to pressure, position, and deep static touch, and thus serve to detect and analyze shapes and edges.

Physiologically, Merkel cells are somewhat rigid, and are not encapsulated. The cell structure involved consists of an enlarged nerve terminal intimately associated with a nerve ending, and forms what is termed a Merkel cel-neurite complex. Merkel cells and Meissner’s corpuscles are found in superficial skin layers, and are clustered beneath the ridges making up our fingerprints. Merkel nerve endings in hairy skin cluster in specialized structures referred to as touch domes or hair disks.

Neurologically, one afferent nerve fiber is capable of innervating up to 90 such endings, wherein each Merkel cell stores neuropeptides which, on being released to the nerve ending associated with it in response to pressure, causes the complex to “fire” and send a signal to the brain. Signal transmission is most rapid when the skin is stimulated by point objects that concentrate pressure in a small portion of the skin, and is reduced when pressure is applied with flat or curved objects. Pressure from rounded, i.e., convex, objects produce the slowest signal transmission of all. Of all human skin mechanoreceptors, Merkel cells are most sensitive to low-frequency vibrations (5-15 Hz). They are often sensitive to tissue displacements of less than 1 μm.

Ruffini endings, Ruffini Corpuscles, or Bulbous Corpuscles

Ruffini Endings (Source: Henry Vandyke Carter – Henry Gray (1918) Anatomy of the Human Body, Gray’s Anatomy, Plate 937; now in public domain).

This mechanoreceptor, variously referred to as Ruffini endings, Ruffini corpuscles or Bulbous corpuscle, is a slowly adapting mechanoreceptor located in the deep layers of human cutaneous tissue, where they register mechanical joint deformation as a function of angular change, with a resolution of 2.75 degrees. Ruffini endings are now recognized as the primary mechanoreceptor in periodontal ligaments, the group of specialized connective tissue fibers that attach teeth to the alveolar bone.

Physiologically, Ruffini endings are enlarged, spindle-shaped, elongated, encapsulated dendritic nerve endings.

Neurologically, it is sensitive to skin stretch, responds to sustained pressure, shows little adaptation, and contributes to the kinesthetic sense and control of finger position and movement. Thus it is found in high densities around the fingernails where it enables the brain to monitor slippage of objects along the surface of the skin. This, in turn, allows the brain to modulate one’s grip on an object.

The Bottom Line…

Though this article has covered a wide range of subjects, it has a point. To that point we now seek to come. It has several elements, and those elements will be elucidated here over time. Be patient, please, as I work to make sense out of this complex subject.

First, it is a mistake to rule out the presence of biological causes for skin conditions, even when a biological organism cannot immediately be found. Though psychological issues are now well-known and respected causes of such conditions, a number of biological causes that are difficult to diagnose are also known to exist, and those causes can manifest in individuals who have many if not all the other signs and symptoms of ES/DP.

It is never wise to refer to a wheal of unknown etiology as a “bite.” Instead, such conditions should be categorized, thought of, and spoken of as “skin lesions,” because calling them bites presupposes a fact not in evidence. Skin lesions that occur as the result of an unwitnessed event cannot, as a rule, be diagnosed as having a specific cause without further investigation. The cause is just as likely to be the result of chemical changes in the victim’s body as from a spider, mite, or other biting organism.

Second, though, the person afflicted with a skin condition of unknown cause is wise to not jump to the conclusion that the cause is biological without further investigation by a professional, experienced investigator. Other possible causes should be ruled out first. Among these are the presence of unusual emotional stressors caused by, for example, the loss of a loved one, divorce, legal and financial issues, mid-term or semester exams or similar tests, onset or cessation of menses, etc. Such stresses are not only emotional but physiological as well. We are not the same person we were yesterday. Our body changes as we age, to a degree we only faintly fathom. With those physiological changes come expressions of hormonal actions and reactions that ripple throughout our bodies, and sometimes the reactions result in skin lesions.

Third, and perhaps most important, the presence of a mild, transitory, or infrequent skin condition that produces one or a small number of skin lesions of short duration is not something that one should necessarily become alarmed about. In fact, most of the time no alarm at all is warranted, and in no case is excessive alarm justified. Life is not conducted linearly, but has its turns, bumps, and twists. Some of those result in skin issues that are temporary, while some are more lasting. Few, in the vast majority of cases, are life-threatening. Take time to consult with one or more professionals. Study for yourself, too, but use authoritative sources, particularly sources that are associated with a recognized medical or academic community, and avoid those that push a sensational agenda.

Most important, as you are patient with me as I work to flesh out this paper, be patient with yourself and those with whom you seek counsel. Don’t assume your condition will worsen, and if it does take a turn for the worst, don’t assume it will continue to grow worse over time.

Important Additional Food for Thought…

PLEASE NOTE: Nothing in the following, or in the foregoing, should be used or taken as a substitute for advice from a licensed medical professional.

The following is for those who believe they are being attacked by one or more biological organisms that are causing skin lesions on their bodies but which have yet to be found, much less identified. 

First, as repeated time and again in the material presented earlier in this paper, your skin lesions may be caused by something other than a biting organism. Just because a lesion looks like a bite does not make it so. In fact, most likely the number of skin lesions emanating from other causes eclipses those caused by biting organisms:

As each of us goes through life we regularly find ourselves with rashes, bumps, reactions, etc., from causes we know have nothing to do with biting organisms; in those cases we just happen to be aware of the specific cause/effect relationships involved (e.g., persons allergic to cats who break out on entering homes with copious amounts of cat hair and dander, and individuals with peanut allergies who react on contacting surfaces they later discover had been contaminated with peanut oil)… 

Not only are many of the rashes, bumps, and reactions we experience in life from causes other than biting organisms, but the manifestations of these lesions — i.e., they way they look, feel, and evolve — depend on a long list of difficult-to-assess variables. Do the math. Every variable added to this equation multiplies the possible outcomes, often in unexpected ways. If the lesion emanates from a foreign organism, many of these variables relate directly to the causal organism, but an equal or even greater number relates to the sufferer, alone. These variables include, for example, the sufferer’s genetic makeup, age, state of health, activity level, lifestyle, and diet. Practically all of these sufferer-specific variables are also affected by the sufferer’s psychological and emotional states, and by the often myriad, cryptic, and even unconscious steps the sufferer takes to ameliorate the lesions’ effects.

But what if the sufferer’s lesions emanate strictly from conditions internal to, and fully associated with, the afflicted individual? What if no foreign organisms of any kind — excluding even those parasites the sufferer may believe to have invaded his or her body — are involved? Is that even possible? Without doubt, the answer to this question is a resounding yes, and in most of those cases the sufferer thinks the cause lies somewhere else. Such cases are anything but rare, but likely comprise a large fraction — perhaps even the largest fraction of all — of the total. For that large fraction, the long list of sufferer-specific variables cited in the previous paragraph still come into play. Barring an exhaustive investigation, it is often not possible to easily distinguish such cases from those caused entirely by foreign organisms.

This explains why the subject at hand is so complicated. Multifactorial issues of this nature defy simplification, and that explains why even vigorous attempts by most who suffer from unexplained skin lesions to obtain good answers, are so often frustrated. On one hand, it is possible that a weighty, multi-volume, encyclopedic work could be written on this subject without even breaking the surface. On the other, however, those suffering from mysterious skin lesions still need answers, even if such answers cannot be provided in terse and pithy explanations that are easy to comprehend. This article has sought to shed that kind of light on the subject. In the process, it is possible, even more than likely, that nothing has been done beyond exposing the smoke, while leaving the fire fully cloaked in mystery.

As mentioned earlier, the fourth dimension — time — plays a big part in the overall picture, and one that must not be ignored. The sufferer must recognize the difference between precipitating events and mitigating and/or exaggerating ones. Consider this: the condition that precipitates a skin lesion or series of them might cease immediately afterward. If the sufferer does nothing at all, lesions emanating from such causes would quickly disappear. Yet, as earlier discussed, many if not most sufferers over-react, applying salves, lotions, emollients, antibiotics and over-the-counter medications, etc., that can cause relatively benign lesions to grow into serious, weeping sores that last, and last, and last…

True, many of those suffering from unexplained skin lesions become their own worst enemies. Don’t misunderstand, though. It does little good to blame the victim, even if the victim has a role in the progression of his or her malady. In point of fact, there is plenty of blame, in other quarters, to go around. Dermatologists, for example, are notorious for pointing their patients in the wrong direction where such skin lesions are concerned. They are prone to doing this because the exigencies of their profession deny them the time, investigatory instruments, and skills needed for accurate diagnoses of skin issues caused or exacerbated by ecological and environmental influences. Yet, it would be wrong to blame dermatologists, alone, for this lack. Most dermatologists who insisted on investigating a patient’s home and place of work, to establish all the possible causes behind the patient’s skin lesions, would soon go bankrupt. Yet it is folly to expect a dermatologist to divine, in the course of a single — or even in a few — clinical consultation(s), all of which are performed wholly within the confines of the dermatology clinic, the cause of one’s skin lesions. Under such conditions the evidence pointing to a specific cause is impossibly sparse.

The plight of the dermatologist is instructive, and bears elucidation. The sufferer’s dermatologist cannot afford to conduct an in-depth investigation into the causes of the sufferer’s condition, because the sufferer cannot afford to pay for it. If you are one of those sufferers, that fact should give you pause. If your dermatologist cannot afford to do all that needs to be done to arrive at a firm, accurate conclusion about the cause of your suffering, who can? Not this author. Even if the investigator is independently wealthy, the time factor alone would still make doing so an impossible task. In other words, nobody but you can do what needs to be done to get to the bottom of your problem.

But don’t let that get you down. It isn’t that hard. In fact, you are probably doing a lot of what needs to be done already, even if what you are doing isn’t being channeled and organized as well as it needs to be. You are doing that because you are probably the most motivated, of all the people you know, to do that job and do it well.

But first you need to become privy to a closely held secret, one that — once you know it — can be used to unlock all the secrets that surround the malady that besets you at this moment.

That secret is this: The most important thing you can do to get to the bottom of your problem is to take every step you can to restore your health. 

“My health?” you ask. Yes, your health. If you were at the peak of health, you would probably not be suffering from skin lesions of unknown etiology. The author first stumbled on this truth in an indirect way, by studying diseases afflicting trees. Trees that are healthy aren’t, in general, attacked by borers, bacteria, or viruses. Unhealthy trees, particularly trees that are being stressed from lack of water, nutrients, and healthy soils, are susceptible to all the disease agents known to attack their species, while neighboring trees planted in good soils, provided with the right amount of sunlight, water and nutrients, stand tall, disease-free.

What’s true of trees is, from all indications, also true of humans. Like trees, we need to be “planted” in healthy environments, spending time in the outdoors soaking up just enough sunlight, consuming just enough of the healthy nutrients we need, and drinking just the right amount of healthy fluids. It isn’t the author’s place to tell others specifically how to do that, and no attempt will be made here to do such a thing. That’s a job only the affected individual can perform. The message here is a very simple one: those who want to get to the bottom of their skin lesions must first do that job. Get healthy!

One of the most important side issues such individuals must also attend to is stress. The author has amassed considerable evidence that points to the combination of suboptimal health and stress as the most significant factors predisposing people to skin lesions of unknown etiology. Like trees, humans don’t handle stress very well, especially when they are unhealthy. But also, again like trees, humans often manage to deal with stress in heroic ways when their health is on their side. Like trees humans cannot avoid having stress in their lives. Stress is often visited upon most people unexpectedly, as when they go through hormonal changes associated with aging, lose a job, get hit with an impossible assignment at work, experience the loss of a loved one, are faced with a divorce… and the list goes on. Stressors are all around us, and we cannot control how many or when uncontrollable stressors will intrude into our lives. What we can control, at least to some extent, is our health. That is where we must first focus our energies. Then, with our health restored, we need to take steps to reduce or eliminate all the stressors in our lives that we can control. Some of the stressors impinging on us can be controlled, and that is next on our list:

Now, while this is not the place to tell you exactly how to restore your health, there are certain practices that humans engage in that tend to make us more susceptible to stress. It is essential for all who suffer from skin lesions of unknown etiology to give serious thought to putting those practices aside, permanently. Smoking, chewing, or snuffing tobacco, indulging in recreational drugs, excessive use of alcohol, relying on discretionary prescription drugs to mitigate the practice of unhealthy lifestyles, following an unhealthy diet, and so on, all contribute to a condition of suboptimal health. That condition makes it more difficult/ if not impossible, to properly handle the stressors life hands us.

The Chicken, or The Egg?

One of the strongest objections commonly voiced to the notion that one should restore one’s health as a prerequisite to getting to the bottom of the cause of skin lesions of unknown etiology is this: “My skin lesions are the reason my health has deteriorated; how can I be expected to restore my health when my skin is under attack?

It’s a good question. Here’s one practical answer:

If, indeed, your health is a direct consequence of the attack you are experiencing, from an unknown agent or organism, then it is asking too much for you to restore your health before that agent or organism is found and dealt with.

Unfortunately, however, it is difficult, and in many cases impossible, to establish which came first, your suboptimal health, or your skin lesions. Often, we don’t realize our health is deteriorating, especially if that deterioration takes place over a period of months or years. Like the proverb about boiling a frog slowly, so it doesn’t realize what is happening until it is too late to jump, it is easy for us to let ourselves go little by little until something bad surfaces that wakes us up to our plight. Unlike the proverbial frog, though, once we are awakened to what is happening, we can usually do something about it. Skin lesions from an unknown cause can, and sometimes are, the message telling us our health has reached a dreadfully low point; if that is your case, rejoice, because now you’ve been told, you can do something about it.

You can perform a simple test to see if this situation might fit your case. Write down a list of the unhealthy habits that you have been engaging in over the past year. If they do not include any of the ones mentioned above, you are an unlikely candidate, but if they include even one of those habits, you just may be one; if they include two or more, the likelihood your skin lesions are a result of your state of health rises considerably.

More to come…


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One comment on “Connecting the Dots: Causes Behind Mysterious Bites, Sensations of Bites, and Skin Disturbances

  1. Mesothelioma prognosis Sep 13,2017 6:32 am

    Thanks a lot for posting, your post is very useful

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