The Dermatobia hominis, commonly known as the botfly, is a member of the family Cuterebridae. There are approximately 150 known species in the world. All the families of the botfly produce larvae that live as parasites within the bodies of humans or other mammals. The botfly is most commonly found in warm and damp climates such as Brazil and Chile. They are not strictly limited to this area and other countries with botfly encounters include Afghanistan, Costa Rica, Dominican Republic, Jamaica, Canada, and even the United States.
The botfly is just under an inch long, hairy, it has a yellow face, orange legs, a metallic blue abdomen, and a round-like body that has similar physical qualities of a bumblebee. The Botfly strongly resembles a normal house fly except for its larger body shape. The maggots that are produced by the bot fly and later hatched on humans, resemble a normal maggot and are about the size of a dime. They have rings of black spines that allow them to stay latched inside human flesh as well as a small pin hole that allows them to breathe while they are burrowed beneath the skin. (Figure 1; left, shows the small pinhole that allows the maggots to breathe. Figure 2; right, shows the spines that surround the body to help the maggot latch to the skin.)
III. Form & Function:
The human botfly has one of the most interesting ways of reproducing. Because of its large size, the botfly would be easily recognized if it landed on its host and too slow to fly away, so for this reason it needs a “transporter” for its eggs. The botfly captures a mosquito and lays about 30 eggs on the mosquito which are attached by an adhesive the fly produces. When the mosquito lands on a human, the body heat of the human causes the adhesive to melt and the eggs to hatch. The larvae then cling themselves onto the person’s skin. The maggots then begin to eat their way through the human flesh and muscle tissue and hold themselves in place by tiny hooks surrounding their bodies. A large, inflamed, pimple looking blemish appears at the site of the infestation of the botfly. After about 6 weeks the botfly is fully fed and begins to eat their way out and drop to the ground. Adult botflies emerge from the pupas in about 20 days. The adult lifespan of a botfly is only about 9 days so they must quickly seek another botfly to mate with before it dies. The botfly exhibits sexual size dimorphism with adult males being larger than females. They are most likely to reproduce during a warm/wet season. Adult botflies have nonfunctional mouth parts and do not feed. (Figure 3; left, shows a mosquito landing on a human while the body warmth melts the adhesive and the maggots are on the skin. Figure 4; right, shows the maggot burrowing in the skin and the breathing hole above the skin as well as the black spines.)
IV. Impact on the World/Humanity:
After the adult bot fly attaches its eggs to a host and the host lands on a human, the eggs are released and the maggots begin to burrow in the flesh. The maggots leave a hole so that they can breathe and by doing this they form a large boil and cause serious pain. The maggots secrete an antibiotic to defend themselves against infection while they feed. If undisturbed, the maggot will remain in the human for 6-8 weeks and then fall out. They are very difficult to remove because of the hooks that surround their bodies. The only way to remove the maggot is to suffocate it by covering up its breathing hole with tape or glue. The worst way to attempt to remove the maggot, is by simply trying to pull it out because it may burst and the pieces left behind can lead to an infection. Depending on where the maggot burrows, it can cause serious tissue damage, but otherwise it will just leave behind a scar.
V. Journal Article Review:
This article is about a child who had a living maggot in his eye and was under the impression it was a dust particle. The child began to itch is eye and rub it thinking that it was dust, dirt, or maybe even an eyelash. He began using drops from the pharmacy until his eye got so swollen he couldn’t see out of it. He went to the doctor and the doctor wanted to perform surgery right away because he was under the impression it may be a cyst. During the surgery, the doctor discovered it was not a dust particle, but a live maggot burrowing and feeding in this child’s eye. (Figure 5; left, shows the removal of the maggot from the eye.)
Botfly. (2010). Wikipedia. Retrieved October 14, 2010, from http://en.wikipedia.org/wiki/Botfly
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