Furuncular myiasis caused by Dermatobia hominis, the human botfly

doi:10.1016/S0190-9622(03)01488-9

Journal of the American Academy of Dermatology

Volume 50, Issue 2, Supplement, February 2004, Pages 26-30

https://doi.org/10.1016/S0190-9622(03)01488-9 Get rights and content

Abstract

Myiasis is a common travel-associated dermatosis. Travelers to many parts of Central and South America are susceptible to infestation by Dermatobia hominis. Despite the common name of human botfly, D hominis infests a broad range of mammals and is a severe pest to economically important farm animals in endemic regions. The adult female does not lay the eggs on the host. Instead, the adult female infests hosts indirectly by using blood-feeding arthropods to serve as phoretic vectors to transport the eggs. We present a patient who acquired Dermatobia when bitten by a day-active mosquito during a visit to Guatemala. He had a locally painful, firm furuncular lesion with a central pore that drained serosanguineous exudates. The patient applied an occlusive ointment and recovered the larva after it emerged. In this report we discuss the life cycle of D hominis, the differential diagnosis, and therapeutic approaches.

Section snippets

Case report

When a 59-year-old sculptor who had returned 2 weeks earlier from a study tour through Mexico and Guatemala squeezed out what he regarded to be the purulent exudate of a furuncle, he was surprised that the content of the lesion presented as a slowly moving, plump, pale yellow larva (Fig 1, B). With panache, he preserved the parasite in a small bottle filled with a splendid white rum and delivered it to our department. On examining the patient, we noted a furuncular lesion with firm flat red

Discussion

This patient's presentation has the characteristic features of D hominis infestation: the parasite was acquired during a visit to an endemic region, it presented as a boil-like cutaneous swelling that was originally diagnosed as a bacterial infection, and it did not respond to antibacterial antibiotics.

Three families in the order Diptera (true flies/2-winged flies) might cause myiasis in man and a wide range of other vertebrate hosts. These are Oestridae (bot and warble flies), Calliphoridae

Acknowledgements

We gratefully thank Prof Dr W Dock for performing the cutaneous sonography and Prof Dr H Aspöck for discussion.

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This supplement is made possible through an unrestricted educational grant from Stiefel Laboratories to the American Academy of Dermatology.

Funding sources: None.

Conflict of interest: None identified.

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Furuncular myiasis caused by Dermatobia hominis, the human botfly☆

Abstract

Section snippets

Case report

Discussion

Acknowledgements

Adv Parasitol

Exp Parasitol

Mayo Clin Proc

J Am Acad Dermatol