Human Botfly: Symptoms & How To Remove

Medical review: Drª. Aleksana Viana
Dermatologist
January 2022

Botfly is an infectious type of disease that is caused by the Dermatobium hominis species of fly, which is gray with black stripes on the thorax and a metallic blue abdomen. This type of infection arises when the larva of the fly manages to enter the skin, even when the skin is intact, leading to the appearance of a painful wound with pus. 

As soon as the first symptoms appear, it is important to consult with a dermatologist, an infectious disease specialist or a G.P. in order to confirm the diagnosis. The larva should be removed as soon as possible, to avoid worsening of the infection.

This type of fly is usually found in humid, mountainous areas such as some parts of Brazil and other tropical countries and, therefore, most people come into contact with them while traveling.

Main Symptoms

After the eggs are laid by the female botfly, the larvae hatch after about six days, and rapidly penetrate the skin, even when the skin is intact and healthy. They can cause some symptoms such as:

  • Formation of wounds on the skin, with redness and slight swelling on the region;
  • Release of a yellowish or bloody fluid from the sores on the skin;
  • Sensation of something stirring under the skin;
  • Pain or intense itching at the wound site.

The diagnosis of botfly in humans is usually made by a dermatologist or an infectologist through the observation of the wound on the skin.

How To Remove a Botfly

Before removing the larva, it's important to verify whether it is already dead, as small fragments of the larva's body could be left inside the skin, making the removal much more difficult. This procedure should always be guided by a physician, but one of the ways of doing it at home is to put a piece of tape over the wound and leave it for about an hour. This will asphyxiate the larva to make removal easier.

After that, the tape should be removed and, on removal, it is necessary to check if the larva has also been removed with it. If not, extra pressure on the outside borders must be applied, to try and get it out. After removing the larva is important to treat the region with a antibiotic ointment, which can be prescribed by a doctor, to prevent further infection by bacteria.

If this is ineffective, the removal of the larva should be done by a doctor with the use of special tweezers. In more severe cases, it may be necessary to perform a minor surgery to cut the skin and widen the hole, allowing the larva to be removed.

How To Avoid Getting a Botfly

Some of the best ways to avoid getting a botfly infection, especially when traveling to a tropical country, include:

  • Closing all windows and doors after it gets dark;
  • Using nets on the windows;
  • Avoid having food or liquids accumulating indoors;
  • Using mosquito repellent.

In addition, in tropical regions it is recommended to iron all clothing before dressing, especially if it has been sun drying, since the eggs of the fly may stick to the fabric.

Was this information helpful?

Atualizado por Tua Saude editing team, em January de 2022. Medical review por Drª. Aleksana Viana - Dermatologist, em May de 2019.

References

  • NEVES, David P. Parasitologia Humana. 12 ed. Atheneu, 2011. 423; 428-429.
Medical review:
Drª. Aleksana Viana
Dermatologist
Post graduate in Clinical Dermatology, Cosmiatric and Surgery by CMMG in 2012 and member no. 16907 of CRM-PE, Brazil.