'Incredibly nasty' botflies invade Seminole County yard

Botflies live under animals' skin

SEMINOLE COUNTY, Fla. – A Winter Springs resident discovered what appeared to be a sick-looking squirrel resting on her window ledge, prompting a lot of questions.

Rene, who asked that News 6 does not use her last name, described the squirrel's infected tumor-looking wounds as "incredibly nasty."

"They were literally nasty, just hanging off their side," Rene said. "I can't even describe it."

Rene photographed it and sent it to the Seminole County/University of Florida Institute of Food and Agricultural Sciences.

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Kaydie McCormick, Seminole County UF-IFAS Extension Agent, confirmed it was a tree squirrel botfly, a parasite that lives and grows under the skin of squirrels and chipmunks.

According the Seminole County UF-IFAS Extension, the tree squirrel botfly has been reported in some 20 U.S. states, including Florida.

"The legless larvae of flies generally are called 'maggots', and the larvae of botflies are often referred to as 'bots'," the UF-IFAS Extension writes on its website. "Commonly reported natural hosts for Cuterebra emasculator include eastern gray squirrels (Sciurus carolinensis), fox squirrels (Sciurus niger) and eastern chipmunks (Tamias striatus). American red squirrels (Tamiasciurus hudsonicus) and flying squirrels (Glaucomys spp.) are rarely reported as hosts. Larvae of bot flies also occasionally infest atypical hosts, such as raccoons, cats, dogs and humans, an affliction termed 'cuterebrosis' or 'cuterebriasis', but which species of Cuterebra are responsible in these cases has seldom been determined. Currently, there is no evidence that Cuterebra emasculator is involved in such situations."

McCormick said there is no evidence that tree squirrel botflies have infected pets or humans, but Rene is concerned about the possibility and no longer allows her dog outside.

"Yeah, we don't even let her out hardly. We only let her out in the side yard because you never know. If they could infect a squirrel, they could infect a dog or cat or someone's pet," Rene said. "And I don't want her bringing it in the house. Of course, I don't want her infected either."

Rene has asked Seminole County to spray the conservation area behind her house, as it does for mosquitoes. Seminole County said it only focuses on mosquitoes and advised Rene to hire a pest control service.

Tree squirrel botflies are different than human botflies, which are found in Central and South America. 

Human botflies burrow beneath a human's skin and often need to be surgically removed.

McCormick said six different studies have documented seven reported cases in the United States since 1999 of human botflies, but all patients had recently been to Central or South America.


About the Author

Erik von Ancken anchors and reports for News 6 and is a two-time Emmy award-winning journalist in the prestigious and coveted "On-Camera Talent" categories for both anchoring and reporting.

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