Australian couple contracts ‘maggots in the body’ while in Bolivia. What is human botfly infestation?

The internet was flush with stories this past week of a young Australian couple who traveled to South America’s Amazon Basin only to be infested with a gruesome looking creature under the skin.

Sydney, Australia couple, Bryan Williams and girlfriend Ally Vagg, both 28, never could have imagined that botflies “maggots under the skin” would of been a concern in the danger-rich Amazon.

In fact, Williams said, “I have traveled to nearly 50 countries over the past five years. This by far is the worst experience,” according to a Brisbane Times report Tuesday.

What is human botfly infestation?

A botfly being extracted from a man’s back.
Image/YouTube Video Screen Shot

This rare and quite disgusting condition is known as myiasis, an infection or infestation of the body of animals and more rarely, humans, with the larva of botflies and related species. In other words– maggots in your body.

Primarily a veterinary issue with livestock, it is most frequently seen Central and South America.

A relatively large fly, the botfly would find it very difficult to place its eggs on a person. To rectify the situation, the clever botfly hijacks a much smaller mosquito in flight. It then releases the mosquito and it goes on its way looking for a blood meal.

When the mosquito does take a blood meal, either on a human or an animal, the body heat of the mammal causes the eggs to hatch. At this point the newly hatched larvae burrow into the host and reside in the tissue.

Some species of dipteran flies may actively try to place the eggs in the eye by flying into the eye (ocular myiasis). This sometimes occurs to people working with livestock in underdeveloped countries.

In the skin or eye the larva matures to a relatively large size over a period of a couple of months. When completely mature, the larva emerges from the tissue and drops to the ground where it becomes an adult fly and the cycle repeats.

The symptoms in the person begin with a nodule that contains one larva. The nodule continuously seeps blood and pus because the larva needs to keep the wound open to breath.

The can be itching and occasionally serious pain when the larva moves. Secondary bacterial infection can occur.

To treat botfly infestation is to remove the larva. Cutting off the air supply (using vasoline, tape, etc.) causes the larva to emerge and can then carefully be pulled out with tweezers. They can be difficult to remove because of backward facing barbs that secure it in the hole. Some people choose to let the larva develop and emerge naturally.

Surgery in not usually necessary unless the larva dies in the tissue and cannot be removed. The use of insect repellent and protective clothing that prevent mosquito bites can help prevent infestation.

Click this link to see a video of a botfly extraction—Warning: not for the squeamish.

This map depicts the physical region of the human bot fly.
Image/Chelsea Fugate via Wikimedia Commons