Painful Lumps on Woman’s Scalp Turn Out to Be Parasitic Botfly Larvae

May 30, 2019 Updated: May 30, 2019

A British woman’s itchy lumps on her scalp after a trip to Argentina turned out to have been parasitic botfly larvae.

The 50-year-old woman, who was not identified by name in the BMJ Case Report, sought treatment for her condition, which a doctor initially diagnosed as cysts.

But when over the next three weeks the “cysts” began oozing a clear fluid and became more painful, another cause was suspected.

“By the time she was admitted to the hospital, seven weeks after returning to the U.K., the cysts were approximately 2-cm in diameter, raised, but not inflamed, each with a noticeable central punctum,” the case report reads.

A doctor then suggested the lumps might have been caused by an infestation by botfly larvae, whose spines can cause pain to the human host.

One way botfly larvae can be removed is by sealing the breathing hole with vaseline, which forces the creatures to the surface so they can be removed using tweezers.

Squeezing them out is risky as they may rupture. In extreme cases, the bodily fluids of the squashed botfly larva can cause severe anaphylactic shock.

According to the case report, the doctor tried sealing the breathing hole with vaseline, and this approach worked to extract one larva. Another larva died while in the woman’s head, needing a surgical intervention to get it out.

“The patient was taken to the theatre (operating room) by the plastic surgery team the following day and the remaining larva was removed under local anesthetic. Both wounds were washed out with saline and antibiotic ointment was applied to the scalp,” the report said.

A deer botfly. (Creative Commons Attribution 3.0 Unported license)

The report’s authors said that one way humans can become infested with botfly larvae is by means of a process called phoresis. This is when a botfly catches a mosquito and lays its eggs on it. When the mosquito bites a human, it transfers the eggs.

“The warmth of the host’s body triggers the fly eggs to hatch, and the larvae then burrow into the subcutaneous tissue,” according to the case report. “Here they can remain anywhere between 4 and 18 weeks.”

The patient said she had traveled to Iguazu Falls in South America and had been bitten by mosquitos several times while on her trip.

According to the University of Florida’s website, “The human bot fly, Dermatobia hominis, is a large, densely haired fly that looks like a bumblebee.  The human bot fly is native to Central and South America.”

While the fly is not known to transmit disease, the larvae of the insect “will infest the skin of mammals and live out the larval stage in the subcutaneous layer, causing painful pustules that secrete fluids. The infestation of any fly larvae inside the body is known as myiasis,” the university says.

*Warning: graphic video showing botfly larvae being removed from under human skin.*

Doctors Find ‘Sweat Bees’ In Woman’s Eye

The incident recalls the case of a woman in Taiwan who checked into a hospital complaining of intense eye pain and was found to have four live bees inside her eye, feeding off the salt and water in her tears.

CTS News reported on April 3 that a woman identified only by her surname—He—was treated at Fooyin University Hospital in Taiwan.

An eye doctor who examined He discovered there were four small sweat bees wriggling around on the inside of her eyelid.

The hospital’s head of ophthalmology, Dr. Hong Chi Ting, told the BBC he was “shocked” to find four live insects in the patient’s eye socket.

“I saw something that looked like insect legs, so I pulled them out under a microscope slowly, and one at a time without damaging their bodies,” Hong said, according to Business Insider Singapore.

The doctor told a news conference that the bees had been feeding off the woman’s tears.

Hong was cited by the BBC as saying the bees were about 4 mm (5/32 inch) in size.

Weeding a Grave

The woman had reportedly been out pulling out weeds from around the graves of relatives as part of the Chinese Qing Ming tomb-cleaning festival.

“I was visiting and tidying a relative’s grave with my family,” He told reporters, The Washington Post reported. “I was squatting down and pulling out weeds.”

She told reporters a gust of wind blew something into her eyes, and she thought it was dirt. She flushed the area with water, she said, and out of fear she might damage her contact lenses, the woman avoided rubbing her eyes.

Hong told the BBC she was lucky not to have rubbed her eyes because that may have caused the bees to release venom, leading to blindness.

“She was wearing contact lenses so she didn’t dare to rub her eyes in case she broke the lens. If she did she could have induced the bees to produce venom… she could have gone blind,” Hong said, according to the report.

Hours after the insects flew into He’s eyes, discomfort turned to pain. The following day it became so intense, she sought medical attention.

“She couldn’t completely close her eyes. I looked into the gap with a microscope and saw something black that looked like an insect leg,” Hong told the BBC.

“I grabbed the leg and very slowly took one out, then I saw another one, and another and another. They were still intact and all alive.”

Close-up images of the bees embedded in the woman’s eyes were shown on Taiwanese TV.

First Case Ever?

Hong told the BBC he believes this is the first case in Taiwan of sweat bees infesting someone’s eye socket.

Matan Shelomi, an associate professor of entomology at National Taiwan University, told The Washington Post that this may, in fact, be the first time in recorded history such an incident has ever occurred.

“To my knowledge, this is the first case of a bee or a wasp getting caught in a part of a person’s anatomy, as far as I know,” he said, The Post reported. “I’m sure the sweat bees got by the eye and got squished between the eye and eyelid. They were in the wrong place at the wrong time.”

He was discharged and is expected to make a full recovery, KRON-TV reported.

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