Dermatobia hominis

Human Bot Fly
J. Eibl 2007, WikiMedia Commons

Human Bot Fly Larvae - Captain R. Goodman 2007, WikiMedia Commons

Also known as:

Human bot fly Torsalo Berne Ura

Scientific Classification

Class	Insecta
Order	Diptera
Family	Oestridae

Hosts

Humans, many birds and most domestic and wild animals.

Identification

The mature larvae may grow up to 25mm in length. D. hominis are similar to Calliphora in appearance. They have a blue-black abdomen, and have yellow-orange head and legs.

Larvae are distinctive as they taper towards the posterior end

Life cycle

The adults do not feed, and draw food from the larvae, which accumulate stores throughout their developmental stage. The female then catches an insect, most commonly the mosquito, and lays a batch of eggs on it.

The insect lands on a host, and the L1 larvae then hatch on the host, and quickly penetrate the skin. They then undergo a transformation to L2, and then subsequently to L3. The larve fully mature, and the move to the ground to pupate. Then then emerge later as adults.

• Eggs laid on blood sucking flies such as mosquitoes
  • These hatch when the mosquito next lands on a warm blooded animal

• Larvae penetrate skin causing painful swellings

• Larvae emerge after 35-42 days and fall to ground to pupate

• 4 month life cycle

Pathogenesis

• In humans, the larvae are most often found in swellings on the head and limbs

• Larvae cause painful swellings and distress to cattle

• Larvae cause production losses

• Wounds caused by exiting larvae can increase the prevalence of attack by other myiasis flies