myiasis

Introduction

Direct invasion of tissue by insect larvae, especially maggots of the metallic-colored screw worm flies or botflies.

Etiology

• Furuncular myiasis:
  • Dermatobia hominis (human botfly)
  • Cordylobia anthropophaga (African tumba fly)
• Creeping dermal myiasis: (see etiologic agents)
  • Gastrophilus intestinalis (horse botfly)
  • Hypoderma (cattle botflies)
• Wound & body cavity myiasis:
  • Chrysomyia bezziani (screw worm fly)
  • Cochliomyia hominivorax
  • Wohlfahrtia vigil
• Intestinal myiasis:*
  • Eristalis tenax (drone fly)
• Ophthalomomyiasis:
  • Oestrus ovis (sheep botfly)
  • agents of furuncular & wound & body cavity myiasis may also cause ophthalomomyiasis

* most instances in which maggots are found in human feces result from deposition of larvae by flies on recently passed stools

Epidemiology

• unconscious & debilitated patients at risk

Pathology

• larvae are deeply invasive into viable tissue, producing large suppurating lesions
• larvae that infest wounds may also infest body cavities such as the mouth, ears, sinuses, anus, vagina & lower urinary tract
• Ophthalomomyiasis:
  • eyelid nodules
  • retinal detachment
  • destruction of the globe

Clinical manifestations

• variable from harmless colonization to destruction of nose, meningitis & deafness

Management

• removal of maggots & debridement of tissue

More general terms

• parasitic infection

Additional terms

• larva
• maggot