Content
Human myiasis is the infestation of fly larvae on the skin, in which these larvae complete part of their life cycle in the human body by feeding on living or dead tissues and which can happen in 2 ways: vermin or berne. The tailworm is caused by the blowfly, and the berne by the common fly. The main characteristics of each type are:
- Mouthpiece: The fly Cochliomyia hominivorax it lands on the injured skin and lays 200 to 300 eggs, which turn into larvae in just 24 hours and which feed on living or dead tissues. After this period they fall and hide in the soil in the shape of a pupa, which after a few days will give rise to new flies.
- Berne: The fly Dermatobia hominis puts a larva on the skin and after about 7 days and actively penetrates the skin where it will stay for about 40 days feeding on living or dead tissue. After that period it falls and hides in the soil in the form of a pupa, which after a few days will give rise to a new fly. The larva maintains an open hole in the skin through which it can breathe, and so, when covering this opening, the larva can die.
This type of infestation can affect humans and domestic animals, cattle, sheep and goats, for example, and it is also possible to have vermin and berne at the same time, especially in animals that are not inspected daily.
Berne Bicheira
Main symptoms
The symptoms of human myiasis can appear anywhere on the body, including the eyes, ears, mouth or nose, causing great discomfort. Its main signs are:
- Berne: 2-3 cm wound on the skin, open, with pus and liquids. By pressing, you can see the white larva at the site
- Nipple: Open wound on the skin, of variable size, full of small larvae and a bad smell in the area, which can cause severe hemorrhages when they proliferate in the cavities
Myiasis in humans especially affects people in poor hygiene and basic sanitation, as well as alcoholics, dirty people, who sleep on the streets and who have skin wounds, bedridden or mentally disabled.
How the treatment is done
The treatment for tailworm and berne consists of picking the larvae, an unpleasant and painful process, and therefore it is also recommended to take ivermectin in two or three doses, under medical advice, to avoid secondary infections and to clean the region before starting the removal of the larvae. It is important that treatment is started at the very beginning of the disease to prevent disease progression, as the larvae are able to quickly destroy the tissues.
The use of oil, alcohol, creoline or other substances directly on the wound does not seem to be effective, and causes intense discomfort, because it causes discomfort in the larvae that may try to enter the wound even more deeply, making its removal difficult. So, the most recommended is to remove the larvae with tweezers and take the antiparasitic medicine, which will be able to kill and eliminate the larvae in about 24 hours.
In the most severe cases, it may be necessary to have a small surgery to cut the skin and widen the orifice, allowing the larva to be removed. In addition, when the lesion is very extensive, it may also be necessary to perform plastic surgery to reconstruct the tissue.
How to prevent infestation
To avoid infestation with fly larvae in humans, it is important to maintain good hygiene habits, bathing daily with scrubbing with water and soap, taking good care of all wounds and scratches, keeping them clean and disinfected, applying antiseptic lotion daily, taking all necessary care to avoid cuts and scratches.
It is also important to keep flies away, avoiding the concentration of waste exposed to the open air, and using insecticide whenever necessary to keep flies out of the house. Bedridden people need extra care because they do not have the same defense capacity, requiring an attentive caregiver, who bathes, takes care of hygiene and keeps wounds properly clean.
Created by: Tua Saúde Editorial Team
Bibliography>
- BRAZILIAN SOCIETY OF DERMATOLOGY. Myiasis. Available in: . Accessed on 24 Oct 2019
- BARNABÉ, Anderson S. Epidemiology of cutaneous myiasis: Literature review. Minutes of Health Sciences. Vol 04. 2 ed; 14-22, 2016
- NEVES, David P. Human Parasitology. 12th ed. Publisher Atheneu, 423-432.