Cuterebra Removal

Adult Cuterebra flies are large and bee-like and do not feed or bite. Females deposit eggs around the openings of animal nests, burrows, along runways of the normal hosts, or on stones or vegetation in these areas. A female fly may deposit 5-15 eggs/site and >2,000 eggs in her lifetime. Animals become infested as they pass through contaminated areas; the eggs hatch in response to heat from a nearby host. In the target host, the larvae enter the body through the mouth or nares during grooming or, less commonly, through open wounds. After penetration, the larvae migrate to various species-specific subcutaneous locations on the body, where they develop and communicate with the air through a breathing pore. After ~30 days, the larvae exit the skin, fall to the soil, and pupate.

Cuterebra lesions are most common in the summer and fall when the larvae enlarge and produce a fistulous swelling ~1 cm in diameter.

Cuterebra

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A Cuterebra is an opportunistic parasite found under the skin of small mammals. This parasite is the larval stage of the Cuterebra fly, who uses animal hosts to complete its life cycle.

The adult files are large and do not feed on or bite animals. Eggs are deposited around animal burrows and on plants, rocks and other objects. The eggs stick on the animal host as the host passes by, and then the eggs hatch in response to the body heat of the animal. The hatched larvae enter the body through the mouth or nose during grooming, or less commonly, through an open wound in the animal.

The larvae then migrate to specific areas on the body under the skin. The larvae make a small hole in the skin to breathe. This is when the parasite is usually discovered; a noticeable lump in the skin with a small hole. The tip of the larve will often be visible deep in the hole. Roughly 30 days later, the parasite exits the animal host, pupates on the ground, and becomes an adult fly.

It is very important to NOT squeeze the skin in hopes of getting the larva out. This can cause the larva to break apart, and cause the host animal to have a chronic infection or perhaps an anaphylactic reaction.

If you suspect your pet has a Cuterebra parasite, please contact your veterinarian as soon as possible for proper removal and treatment of any secondary infections.