Phorids, Not Gnats: Ivermectin Treatment of Scuttle Fly Myiasis in Nursing Home Resident

A well-cared-for, bedridden, and helpless 94-year-old female resident in a Tennessee nursing home experienced sudden, rapid weight loss, severe lethargy, and increasingly foul-smelling bed sores between late February and April 2022. By April 5, her modern, climate-controlled room became infested with small flies, initially identified as “gnats” by staff. Despite immediate pest control measures—removal of plants and food, spraying, sealing drains, and deploying insect traps—the infestation intensified, with hundreds of tiny flies spreading to other rooms by April 12. By April 13, the facility administration, out of options, considered isolating the patient. On April 14, her family identified the flies as parasitoid scuttle flies, Megaselia scalaris (Lowe, 1866) (Diptera: Phoridae), a species capable of human myiasis.