Maggots can absolutely get into your skin, and the medical term for it is myiasis, an infestation of living tissue by fly larvae. It happens in three main ways: larvae burrow directly into intact skin, they migrate through tissue beneath the surface, or they colonize an existing wound. The condition is far more common in tropical regions, but it shows up in temperate climates too, including in the United States. How you get it, what it feels like, and how it’s treated depend heavily on which type of fly is responsible.
How Maggots Actually Get Into Skin
The idea of a fly larva living inside your body sounds like a horror film, but the biology behind it is surprisingly varied. There are three recognized clinical patterns of skin myiasis: furuncular (a boil-like lesion), creeping or migratory (a larva tunneling under the skin), and wound myiasis (larvae colonizing a pre-existing wound or sore).1PubMed. Cutaneous myiasis: a review of the common types of myiasis Each pattern is caused by different fly species with different strategies for reaching your tissue.
In furuncular myiasis, a single larva penetrates intact skin and develops inside a small cavity just under the surface, creating something that looks and feels like a boil. The two most common culprits are the human botfly (Dermatobia hominis), found across Latin America, and the tumbu fly (Cordylobia anthropophaga), found in sub-Saharan Africa. These two species account for most furuncular cases seen by doctors worldwide.2PubMed. Cutaneous myiasis: review of 13 cases in travelers returning from tropical countries
Wound myiasis is different. Flies like the New World screwworm (Cochliomyia hominivorax) and Old World screwworm (Chrysomya bezziana) lay their eggs directly on open wounds, ulcers, or damaged skin. The hatching larvae then feed on the tissue, and unlike the botfly, these species can produce dozens or hundreds of larvae in a single wound.
The Botfly’s Bizarre Delivery Method
The human botfly deserves special attention because its life cycle is genuinely strange. The adult female doesn’t land on you at all. Instead, she captures a blood-feeding insect like a mosquito, glues her eggs to its body, and releases it. When that mosquito lands on a person to bite, body heat triggers the eggs to hatch, and the tiny larvae drop onto the skin and burrow in.3PubMed. Furuncular myiasis caused by Dermatobia hominis, the human botfly You feel the mosquito bite. You don’t feel the larvae entering.
This indirect strategy is vital to the parasite’s survival. The adult botfly is large and conspicuous, so landing on a human to deposit eggs would be risky. By using a smaller, stealthier insect as a courier, the fly dramatically improves its chances.4International Journal of Insect Morphology and Embryology. Morphology of the eggs of the human bot fly, Dermatobia hominis (L. Jr.) (Diptera : Cuterebridae) and their adherence to the transport carrier From the victim’s perspective, the infestation seems to arise out of nowhere, because the actual exposure felt like nothing more than an ordinary mosquito bite.
The tumbu fly uses a completely different trick. It lays eggs on soil, clothing, or towels left outside to dry. When a person puts on infested clothing or lies on contaminated bedding, the larvae hatch on contact with warm skin and bore in. One case report described a medical student who visited Tanzania and developed a furuncular lesion on his foot about three weeks after returning to the United States, caused by a tumbu fly larva picked up during his trip.5PubMed Central. Furuncular myiasis of the foot caused by the tumbu fly, Cordylobia anthropophaga: report in a medical student returning from a medical mission trip to Tanzania
What It Feels Like
The symptoms depend on which type of myiasis you have, but the most commonly reported version, furuncular myiasis, produces a painful, firm lump that resembles a boil. There’s often a small central opening or pore visible on the surface. Many people describe intermittent sharp, stabbing pains, sometimes accompanied by a sensation of movement under the skin. Serous or bloody fluid may drain from the pore.6PubMed Central. Cutaneous furuncular myiasis: Human infestation by the botfly
The problem is that these lesions look a lot like other things. Doctors who haven’t seen myiasis before frequently misdiagnose it as a bacterial boil, cellulitis, an insect bite reaction, or even a sebaceous cyst.6PubMed Central. Cutaneous furuncular myiasis: Human infestation by the botfly In non-tropical countries, the diagnosis is often delayed because the condition is rare enough that it doesn’t come to mind during a routine exam. A travel history is the single most useful clue. If you recently visited Central America, South America, or sub-Saharan Africa and develop a boil-like lump that doesn’t respond to antibiotics, myiasis should be on the radar.
Wound myiasis tends to be more visually obvious. You can often see larvae moving within the wound. In severe cases involving screwworm flies, the tissue destruction is dramatic and the smell is distinctive. Creeping myiasis, caused by larvae migrating beneath the skin rather than staying in one spot, produces a raised, reddened, snake-like track that moves a few centimeters per day.
Who Is Most at Risk
Travelers to tropical regions account for most furuncular cases diagnosed in places like the United States and Europe. But wound myiasis, which involves larvae colonizing existing wounds rather than burrowing into intact skin, has a different risk profile. A study collecting cases from 20 medical centers across the United States found 42 cases of domestically acquired myiasis. Most involved pre-existing wounds, and the people affected tended to be older (averaging about 60 years old) and predominantly male. Homelessness, alcoholism, and vascular disease were common factors.7JAMA Network. Wound Myiasis in Urban and Suburban United States The fly most often responsible in these domestic cases was the green blowfly (Phaenicia sericata), not an exotic tropical species.
More broadly, the recognized risk factors for developing myiasis include open wounds, diabetes, poor hygiene, low socioeconomic conditions, psychiatric illness, alcoholism, vascular disease, and cancer.8European Surgery. Wound myiasis in Western Europe: prevalence and risk factors in a changing climate scenario Diabetes and immobilization are particularly notable because they combine reduced sensation (you may not feel larvae entering a wound) with impaired healing (the wound stays open longer, offering a prolonged opportunity for fly contact).9PubMed. Maggot infestation (myiasis) of external fixation pin sites in diabetic patients
Agricultural workers in endemic regions also face elevated exposure. A case report of a 60-year-old farmer described a leg ulcer that became infested with maggot larvae, growing from a small wound into a much larger one as the larvae expanded the tissue damage.10PubMed Central. Maggot Infestation: Various Treatment Modalities
Diagnosis and When Imaging Helps
For a textbook case of furuncular myiasis with a visible central pore and a recent travel history, the diagnosis is clinical. But when the presentation is ambiguous, or when the larva is in a difficult location like the scalp, ultrasound can be genuinely useful. It allows a clinician to visualize the larva’s movement within the cavity and confirm the diagnosis before attempting removal.11PubMed Central. Ultrasound Detection of Human Botfly Myiasis of the Scalp: A Case Report Another report described using ultrasound to diagnose South American cutaneous myiasis, with the added benefit that applying petroleum jelly to the skin can force the larva to partially emerge, confirming the diagnosis visually at the bedside.12Journal of Travel Medicine. Soft tissue ultrasound in the diagnosis of South American cutaneous myiasis
In the U.S. domestic cases studied, the most common species identified was the green blowfly, but flesh flies and humpbacked flies also turned up, and in six cases, two species were found infesting the same wound simultaneously.7JAMA Network. Wound Myiasis in Urban and Suburban United States Identifying the exact species usually requires entomological examination of the extracted larva, which matters for epidemiology but rarely changes how the individual patient is treated.
How Maggots Are Removed
Treatment for furuncular myiasis revolves around one central principle: get the larva out intact. This sounds simple, but the larva has rows of tiny hooklets along its body that anchor it firmly in the tissue. If you try to pull a live larva out with forceps, it can retract and grip tighter, and tearing it apart risks leaving fragments behind that can cause infection or a prolonged inflammatory reaction.
The standard approach is to cut off the larva’s air supply first. Applying an occlusive dressing over the pore for about 24 hours forces the larva to surface because it can no longer breathe. A faster method involves crushing an ivermectin tablet, mixing it with petroleum jelly, and applying the paste over the opening for about four hours. Once the larva is dead or immobilized, it can be extracted with gentle pressure or forceps.12Journal of Travel Medicine. Soft tissue ultrasound in the diagnosis of South American cutaneous myiasis
Almost any occlusive substance works in a pinch. Petroleum jelly, nail polish, beeswax, even raw bacon have all been used. Bacon therapy became surprisingly well known after a case report described how placing a strip of fatty bacon over the lesion drew the larva out intact within two to three hours.13JAMA. Furuncular Myiasis: Alternatives to Bacon Therapy-Reply The mechanism is the same regardless of the material: block the breathing pore, and the larva migrates toward the surface.
For wound myiasis, where many larvae may be present, the situation is more complex. A study of patients with advanced head and neck cancer who developed wound myiasis tested a combination of ivermectin, albendazole, and clindamycin. Maggot counts dropped by roughly 73% within the first day and over 92% by day three, with significant improvement in wound symptoms over the following week.14PubMed Central. Management of Malignant Wound Myiasis with Ivermectin, Albendazole, and Clindamycin (Triple Therapy) in Advanced Head-and-Neck Cancer Patients: A Prospective Observational Study Ivermectin given orally has also proven effective for myiasis in locations where manual removal would be impractical or dangerous, such as orbital infestations where surgery would otherwise be needed.15PubMed Central. Ivermectin treatment for massive orbital myiasis in an empty socket with concomitant scalp pediculosis
When It Gets Dangerous
Most furuncular myiasis resolves cleanly once the larva is removed, with the cavity healing over a few weeks. The real danger lies in wound myiasis, particularly when it occurs in sensitive locations. A study of ear, nose, and throat myiasis found cases where nasal larvae had eaten through the thin bone separating the nasal cavity from the eye socket, destroying an eyeball in the process. Ear infestations caused tympanic membrane perforation in every case studied, and nearly a third of those patients suffered permanent hearing loss from destruction of the tiny bones in the middle ear.16PubMed Central. Otorhinolaryngological myiasis: the problem and its presentations in the weak and forgotten
The gravest risk is intracranial invasion. When larvae in the nose or ears breach bone and reach the brain, the fatality rate has been reported as high as 8%.17PubMed. Aural Myiasis: A Case Report and Literature Review These extreme outcomes tend to occur in people who are unable to protect themselves from flies or unable to seek care promptly, including young children, elderly patients with cognitive decline, and people with untreated psychiatric illness.
In patients with malignant wounds or advanced cancers, myiasis can accelerate tissue destruction beyond what the tumor alone would cause.18PubMed. Cutaneous myiasis in skin cancer and malignant wounds: a systematic review For caregivers of bedridden or immobile patients with open wounds, this underscores the importance of wound coverage and fly exclusion, especially in warm months.
Your Body’s Response to the Invader
When a botfly larva settles into your skin, your immune system mounts a vigorous but largely unsuccessful defense. Eosinophils, which are white blood cells that specialize in fighting parasites, surge to the infestation site within the first ten days and then gradually taper off as the larva matures. Mast cells, another component of the immune response, peak early in the infestation and then again around the third week.19PubMed. Eosinophil and mast cell expression in host skin during larval development of the human bot fly Dermatobia hominis
The larva, for its part, is remarkably well adapted to surviving in this hostile environment. It actually ingests the immune cells your body sends to attack it. Research using microscopy to examine the gut contents of developing botfly larvae found activated neutrophils, a key type of immune cell, living and functioning inside the larval gut for short periods before being digested. The larvae effectively eat your immune response as part of their diet.20PubMed. Activated host neutrophils in the larval midgut lumen of the human bot fly Dermatobia hominis This explains why the immune system alone almost never succeeds in killing the larva; without mechanical removal, the larva simply continues developing until it’s ready to emerge on its own, usually after five to eight weeks.
Prevention for Travelers
Preventing botfly infestation comes down to avoiding the mosquito bites that deliver the eggs. Standard mosquito precautions, including insect repellent containing DEET and long sleeves, reduce the risk. In areas where the tumbu fly is a concern, particularly West and Central Africa, ironing all clothing and towels that have been dried outdoors destroys any eggs deposited on the fabric. This sounds overly cautious until you realize how perfectly the eggs blend in with the cloth, and how quickly the larvae hatch on contact with warm skin.
For wound myiasis prevention, wound care is the main defense. Keeping wounds clean and covered, even minor ones, prevents flies from accessing tissue. This is especially relevant for people managing chronic ulcers or surgical wounds in warm weather. The U.S. cases studied all occurred in pre-existing wounds, which reinforces the point that wound myiasis is largely preventable through basic wound hygiene and fly exclusion.7JAMA Network. Wound Myiasis in Urban and Suburban United States
Controlled Maggot Therapy Is a Different Thing Entirely
It’s worth addressing the obvious question that comes up when people learn about maggot infestations: isn’t maggot therapy an actual medical treatment? It is, but the resemblance to myiasis is superficial. Medical maggot therapy uses a single species, Lucilia sericata, the common green bottle fly, which has been bred under sterile conditions in a laboratory. These larvae eat only dead tissue and leave healthy tissue intact, making them useful for cleaning chronic wounds that aren’t responding to other treatments. A systematic review found that maggot therapy achieved faster debridement and promoted faster development of granulation tissue compared to hydrogel dressings.21PubMed Central. Maggot Therapy in Wound Healing: A Systematic Review
The key distinction is control. In therapeutic use, sterilized larvae are applied under medical supervision, contained within a special dressing, and removed on schedule. In myiasis, wild larvae of species that may consume living tissue invade without invitation and continue feeding until they’re removed or until they complete their development. One scenario is a medical tool; the other is a parasitic infestation. The fact that both involve maggots in wounds is about where the similarity ends.
When the Feeling Is Real but the Maggots Aren’t
Some people present to doctors convinced that larvae or parasites are living under their skin when no infestation exists. This condition, called delusional parasitosis, is an uncommon psychiatric illness in which the affected person experiences vivid sensations of crawling, burrowing, or biting. Patients frequently bring in samples of lint, skin flakes, or scabs as “proof” of the infestation. They typically seek help from dermatologists or primary care doctors rather than psychiatrists and may resist the suggestion that the cause is psychological.22PubMed Central. Delusional parasitosis: Worms of the mind
Bringing this up isn’t meant to dismiss anyone’s concerns. Real myiasis happens, and the symptoms are genuinely disturbing. But if repeated skin examinations show nothing, and no larva or pore can be identified, it’s worth knowing that the sensation of something moving under your skin can have psychiatric causes that respond well to treatment. In contrast, actual myiasis always produces visible evidence: a lump, a pore, a track, or visible larvae in a wound. The two conditions are distinguishable on physical examination, even if they feel the same to the person experiencing them.
Climate Change and Shifting Geography
Myiasis has traditionally been framed as a tropical disease, but the geographic lines are blurring. A study examining wound myiasis in Western Europe noted that changing climate patterns are expanding the range of fly species that cause myiasis and extending the warm seasons during which flies are active.8European Surgery. Wound myiasis in Western Europe: prevalence and risk factors in a changing climate scenario Combined with the vulnerability of aging populations and the growing number of people living with chronic wounds from diabetes or vascular disease, this suggests that wound myiasis may become a more common sight in emergency rooms at higher latitudes in the coming decades. For clinicians in temperate regions, that means keeping myiasis on the list of possibilities when evaluating unusual wound presentations, even in patients who haven’t traveled.