Introduction
Tungiasis was first documented in the 1500s. After being shipwrecked on the Caribbean island of Haiti, the crew of Christopher Columbus contracted tungiasis. Tungiasis affects over 20 million people worldwide. Tungiasis is more common in impoverished people who live barefoot in rural areas, remote villages, and shanty towns in large cities. The condition is more severe in children aged 5 to 14 who were assigned male at birth (AMAB) and the elderly. Tungiasis is thought to affect eight out of ten disadvantaged children who live in sand flea-infested areas.
Tunga fleas can be found on sandy beaches, rainforests, and stables. As it prefers to stay close to the ground, it frequently bites the feet of humans and other warm-blooded animals.
What Is Tungiasis?
Tungiasis is an infection of the skin caused by the burrowing flea Tunga penetrans or a related species. The flea is also known as the jigger, chigoe flea, nigua, pico, sand flea, and bicho de pie (bug of the foot). The flea-caused lesions are distinguished by a white patch with a black dot in the center. It appears as white circles with black dots in the middle. These lesions are most commonly found on the feet but can appear anywhere on the body.
What Causes Tungiasis?
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Tungiasis can be contracted through direct contact with sand fleas on the ground or by contacting the fur of an animal with sand fleas. Sand fleas prefer to live in the fur of cows, pigs, dogs, cats, and rats, and are invisible. The scientific names for the sand fleas that cause tungiasis are Tunga penetrans (T. penetrans) and Tunga trimamillata (T. trimamillata).
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Tungiasis is caused only by female sand fleas carrying eggs. Male sand fleas bite and feed on the blood as well. However, because they do not lay eggs, they do not burrow into the skin and cause tungiasis.
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Female sand fleas bite and claw the epidermis (the outermost layer of the skin), creating an opening. They burrow into the dermis, the middle skin layer, and feed on blood from the blood vessels. The blood provides the nutrients required for the female to produce eggs. The sand flea obtains oxygen from the skin through the bite opening. The black dot in the center of the white circle on the skin is the burrowed sand flea's hind end. This is where the eggs hatch.
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The sand flea can live inside the skin for up to six weeks, growing larger with its eggs and blood. It may eject up to 100 eggs during this time, which fall out of the opening in the skin and onto the ground. The sand flea dies after laying its eggs and falls off as the skin sheds.
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Sand flea eggs hatch into larvae in about four days and start to feed on organic material in the soil. In about four weeks, the larvae develop into pupae, which mature into adult sand fleas. These adults will then seek out people to feed on their blood.
What Are the Signs and Symptoms of Tungiasis?
Bite marks are primarily concentrated in the lower area, closer to the ground. Bite between the toes is one example. The individual is unlikely to feel the interaction with the flea, but the effects will be visible later.
Some of the symptoms are as follows:
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Itchiness - It is seen in the area where the burrowing took place. The flea produces a white nodule with a black center, which is where the patient feels the most itching.
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Pain - Patients may experience significant pain in their feet, causing them to walk differently. The patient's feet are too tender to place firmly on the ground.
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Ulcers - The burrowing of the flea may result in foot ulceration.
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Inflammation - The foot may swell where the flea has entered the flesh, and some patients' feet may become pus-filled in the parasite-affected area.
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Toenail Loss - Fleas can burrow beneath the toenails and cause them to fall off.
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Deformed Toes can be the result of a severe parasitic attack. Because of the pain and discomfort caused by the condition, some people have reportedly wanted to cut off their toes.
What Are the Complications of Tungiasis?
Tungiasis patients are at risk of serious bacterial infections caused by the burrowed insect and scratching at the skin. These infections can permanently disfigure a person's foot and impair their ability to walk.
Other complications include:
How Is Tungiasis Diagnosed?
If a tungiasis infection is suspected, doctors will look for signs of eggs being expelled from the affected area on the feet by the burrowing female flea. Tungiasis can be diagnosed by examining the skin by healthcare providers who provide care in affected areas. Most people in these areas are familiar with tungiasis and recognize it when they have it. Brown strands of feces produced by the flea that hang out of the sores are another visible sign.
A biopsy of the lesions can also be performed to determine whether a parasite is present.
How Is Tungiasis Treated?
Tungiasis often heals on its own because the burrowed flea dies within two weeks and sloughs off naturally as the skin sheds. During the one to two weeks, it feeds on the host's blood; the flea will lay more than 100 eggs, falling to the ground through the lesion's opening.
Medical interventions include the following:
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The flea is physically removed with sterile forceps or needles. The opening must be widened, and extraction can be difficult when the flea is engorged. In many cases, the entire lesion must be removed.
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Topical anti-parasitic medications such as Ivermectin, Metrifonate, and Thiabendazole can be used.
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Suffocation of the flea with a thick wax or jelly and freezing the lesion locally with liquid nitrogen (cryotherapy).
All precautions should be taken to avoid secondary infections such as cellulitis, bacteremia, tetanus, and gangrene.
Conclusion
Many tungiasis patients improve without treatment. However, the painful and itchy symptoms can be distressing until the sand flea dies. Tungiasis can cause infections that threaten limbs and lives in impoverished areas with limited access to quality healthcare. When visiting a sand flea-infested area, precautions must be taken to reduce the risk of developing tungiasis. Wearing closed-toe shoes and ankle-covering socks, or use an insecticide to spray on the feet. It is critical to seek medical attention to remove the sand flea to reduce the risk of infection and other complications.
