Thursday, January 17, 2008
Medical Quiz #3- Answer (see prior post)
This was a toughy. The answer is #4 Furuncular myiasis. This is a human botfly larvae (Dermatobia hominis) emerging from a nodule on the patient's upper arm. The fly's eggs are carried by mosquitoes after the female fly catches the mosquito and attaches its eggs to the body. The eggs hatch and enter the human body when the mosquito is feeding on it. The larvae develops in the subcutaneous skin and after 8 weeks the larvae emerges (like in the photo) and drops off into the soil. They develop in the soil into small gray botflys.
Believe it or not, the wound doesn't usually become infected because the larvae can only survive for 8 weeks in an uninfected body. It may even secrete an antibiotic. The larvae are difficult to remove but duct tape can cut off their air supply and kill them. Yet another great use for duct tape!!!
This species is found in the New World tropics. Fortunately infection is not common. Just remember to travel with your duct tape.
Posted by Toni Brayer, MD at 9:12 PM