Worms that dig into human skin are a concerning phenomenon that can cause discomfort, pain, and potential infections. While rare, a few different worm species have been known to burrow into the skin, including hookworms, threadworms, and loa loa worms.
What are the most common skin burrowing worms?
The most common worms that dig into human skin are:
- Hookworms – Necator americanus or Ancylostoma duodenale species
- Threadworms – Strongyloides stercoralis species
- Loa loa worms – Loa loa filariasis species
Of these, hookworms are by far the most prevalent when it comes to burrowing into skin. Hookworm infections affect nearly 600 million people worldwide. Threadworms and loa loa worms are less common but can still cause symptoms when they invade the skin.
How do these worms burrow into skin?
Hookworms, threadworms, and loa loa worms all use slightly different methods to penetrate into the skin:
- Hookworms – Larvae enter the top layers of skin. They release enzymes to digest the skin and travel between epidermal cells until reaching capillaries to feed.
- Threadworms – Larvae hatch on the skin surface and then actively burrow downwards between cells into the lower dermis layer.
- Loa loa worms – Adult worms move through subcutaneous tissues and cross into skin surfaces where they become visible.
In most cases, the worms penetrate into the skin itself in order to feed on blood, tissue, or cell contents. They can migrate extensively within the dermis and subcutaneous tissues.
What are the symptoms of skin burrowing worms?
When worms invade the skin, they can cause the following symptoms and signs:
- Small red bumps or blisters on the skin
- Intense itching and prickling sensations
- Visible worm movement under the skin
- Sinuous rashes or inflamed tunnels on the skin
- Crawling and pinching feelings under the skin
- Sleep disturbances from sensation of movement
- Soft swollen areas under the skin
- Secondary bacterial infections
The most common locations include the hands, arms, feet, legs, and buttocks. But worms may appear anywhere on the body in random patterns.
Are the worms visible moving under the skin?
Sometimes the worms can be visible moving underneath the surface of the skin, especially with loa loa filariasis infections. The adult Loa loa worms can reach several centimeters in length and occasionally cross into skin surfaces where they can be seen migrating.
With hookworm and threadworm infections, the larvae are microscopic so they will not be individually visible. But their burrowing activity under the skin surface may be apparent and resemble the movement of a small worm or parasite.
What risks or complications can these worms cause?
Potential risks and complications of skin burrowing worms include:
- Secondary bacterial infections of the skin
- Scarring of the skin due to migration tunnels
- Hypersensitivity reactions
- Impetigo
- Cellulitis
- Abscesses
- Loss of skin integrity and ulcerations
- Lymphedema
- Wheezing, coughing, or pneumonia if larvae migrate to lungs
- Intestinal bleeding or anemia from blood feeding
The location of the worms and extent of migration determines the type and severity of symptoms experienced.
How do you diagnose skin worms?
Diagnosing skin worms involves:
- Medical history – discussion of symptoms and exposure risks
- Physical exam – inspection of skin lesions, rashes, blisters
- Microscopic examination – adhesive tape taken from lesions to view larvae
- Biopsy – obtaining skin samples to view worm sections
- Blood tests – check for elevated antibodies or eosinophilia
- Stool examination – look for worm eggs
- Imaging – ultrasounds, CT scans, MRIs to evaluate extent of infection
Combining multiple approaches helps confirm the worm species and rule out other potential causes of similar symptoms.
How are infections with skin worms treated?
Treatment options for skin worms may include:
- Oral anti-helminthic medications – albendazole, ivermectin, diethylcarbamazine
- Topical thiabendazole – applied directly to lesions
- Cryotherapy – freezing lesions with liquid nitrogen
- Surgical removal – for visible loa loa worms
- Antibiotics – if secondary infections develop
- Steroids – to reduce inflammation
- Skin-soothing creams and anti-itch medications
Multiple doses of albendazole and ivermectin over several weeks may be needed to fully clear an infection. Good hygiene helps prevent reinfection through contaminated soils.
How do you prevent getting skin worms?
Prevention measures for skin burrowing worms include:
- Avoid walking barefoot in endemic areas
- Wear protective clothing outdoors
- Frequently wash hands and feet
- Avoid contact with contaminated soil using gloves
- Deworm pets and livestock
- Iron supplementation in high risk children
- Mass drug administration in some regions
- Educating populations on transmission risks
Hookworm infections are most common in tropical and subtropical developing regions with poor sanitation. Travelers should take precautions when visiting these areas.
Can skin worms spread to other people?
Skin worms can sometimes spread between people through direct skin contact. The worms or eggs can also contaminate soil and water sources, putting whole communities at risk.
Some ways skin worms may spread to others include:
- Touching open sores or blisters on an infected person
- Using contaminated bed linens or clothing
- Walking barefoot through infected soil or sand (hookworms)
- Drinking contaminated water (threadworms)
- Mosquito bites transferring larvae (loa loa worms)
- From mother to baby during pregnancy (loa loa worms)
Practicing good hygiene and sanitation is important to avoid passing worms that burrow in the skin to others.
Which worm infections require reporting to health authorities?
Many skin worm infections are reportable diseases that require notification of health authorities when diagnosed. This allows tracking of cases and outbreaks. Reportable worm infections include:
- Hookworm
- Threadworm
- Loa loa filariasis
- Onchocerciasis (river blindness)
- Dracunculiasis (guinea worm)
Doctors and health providers are typically mandated to report these diseases. Prompt treatment can then help control further spread in a community.
Conclusion
Worms that invade the skin, such as hookworms, threadworms, and loa loa worms can cause uncomfortable symptoms but are treatable withmedications. Preventing infection relies on good hygiene when in contact with contaminated soil and prompt treatment of infected individuals. Education on skin worm risks in endemic regions is key. With proper prevention and control measures, further spread can be limited.