Myiasis - a disease, caused by the larvae of some species of flies. Finding larvae and even adults in the cavities, tissues and human bodies, and cause tissue destruction often accompanied by concomitant diseases and infections.
Flies and their larvae feed on decaying tissues, it may be the remains of vegetable or animal origin food, therefore, a major cause of infection are poor sanitary conditions.
Myiasis in humans can occur when non-compliance with the rules of hygiene or as a result of his own negligence or carelessness.
Vitality maggots exceptional, some of them are able to stay alive even in alcohol or formaldehyde for quite a long time. They are able not only to survive, but also to operate and develop in an environment, which may even be hostile. This explains the ability of larvae exist in the human gut.
Some species of insects, able to parasitize the human body, live in Russia.
How do you get infected
The infection can occur in different ways:
- females lay their eggs on the skin, in the eyes, ears, human wounds.
- sometimes it is the result of the bite - the egg injected under the skin
- larvae can be accidentally swallowed, In this case, it may be an intestinal myiasis.
According to the method of infection and the type of existence of human myiasis insects themselves can be divided into the following types:
- random. This kind of diseases cause fly larvae, that develop in decaying organic matter. They may accidentally get into the human body with food, dirty laundry etc.. Hence the name. Flies lay eggs everywhere - on clothes, linen, food. The larvae can be ingested during a meal. With linen eggs can enter the sex organs.
- obligate. In this type of pathogens, caused by fly larvae, occur at a lesion insect species, leading a parasitic way of life. They are herbivorous animals can be infected. Cutaneous myiasis is most often caused by these types of flies.
- optional. These types of myiasis are random, caused by indoor or meat flies, that, attracted by the smell of purulent wounds, can lay larvae in the damaged human tissue.
Pathogens may be larvae 18 species of flies, living mainly in the southern hemisphere, however, some species are found, and in the European part of our continent.
What is this disease
Defeat human insect larvae - dermatomiaz There are two types:
- surface - parasitize larvae on the skin surface, beyond the epidermis do not go.
Cause it can gadfly larvae, People can become infected by contact with these animals. The larvae are very mobile, move rapidly under the skin, gnawing moves up 30 cm. The parasite may be present in the human body to 2-3 months. subcutaneous myiasis, caused by these parasites, It characterized by painful itching, larva moves like long scratches.
The popular name of the disease - "creeping disease". Treatment myiasis wherein - the mechanical removal of the parasite.
- deep - parasites penetrate the skin, located in the deep layers of the epidermis, Sometimes this type of lesion tissue becomes
Insects are able to penetrate even in healthy skin, not only as a result of the bite. Sometimes the infection occurs even in contact with the infected foliage. Many species of flies, able to infect human, live in Africa, North and South America, However, there are species, which meet in Russia, eg, Wohlfahrtia vigil и Wohlfahrtia opaca (Wohlfahrtia Magnifica), different types of sheep, cow gadfly. They also have in Europe, Pakistan, North America.
Infection occurs seasonally, from June to September, while the larvae hatch within a day. In place of the introduction of parasites appear boils. larvae maturation ends in 12-14 day, after which they leave the body of the host and pupate.
- tissue - the defeat hurt the soft tissues, this form can be, when flies lay their eggs in the wound edge, ulcers, wounds, otherwise damaged body surface.
Cases of larval development in the wounds attributed to a separate subspecies of the disease - wound. it increases the danger due to the possibility of joining a secondary infection, Besides, developed symptoms of fever, severe bleeding from the affected regions.
Some species of flies, living in North and South America, capable of even a small wound to postpone 3000 eggs, that, hatched, begin to destroy human tissue and cause serious deep lesions. Insects feel the presence of possible places to lay their eggs, Even a tiny scratch can attract female.
Some insect species are able to penetrate not only into the damaged skin, but also a healthy. The symptoms of this - the occurrence of ulcers, boils with severe itching.
Upon contact with cattle infected larvae may occur horseflies cattle. It is not necessary to touch and stroke the animals - there are cases, when the female insect lays eggs on human hair.
The first stage of infection occurs almost asymptomatic, then may receive little swelling during the movement larvae. In place of the parasite shedding formed fistula, usual localization - the upper body, head. The larva is in the fistula to mature, then through the hole and leaves the body of the host pupate.
The disease manifests itself by strong allergic reactions and symptoms of toxic poisoning organism (nausea, vomiting, even memory loss). Besides, symptoms occur:
- elevated temperature
- short-term pain in the muscles
- may cause pain in the heart.
Particularly dangerous larvae entering the eye. Insect parasitism in this case, can be accompanied by severe pain, swelling of the temporal region, It may lead to a reduction or even loss of vision.
There have been cases of oral myiasis, when it affected oral surface.
Besides, We were cases of penetration of parasites in the brain and spinal cord. In this case, the very mechanism that is not yet defined.
Such contamination of the human intestine (intestinal myiasis) It may occur when eating unwashed vegetables, food, which has long stood uncovered.
Some species of flies live in saline environments cheese or salted fish and can be eaten.
severe nausea, vomiting, pain in the stomach area - these are the main symptoms of the fly larvae. If untreated, may develop colitis (inflammation of the large intestine). In the human gut may be housefly larvae, meaty, falling.
Symptoms of infection: cutaneous myiasis
There are several signs, which can be suspected infection at this disease:
- subcutaneous education appears with itching, feeling the heat, that can grow. Sometimes there is a sense of movement in it
- by having a tumor may change location
- severe weakness, the temperature is increased
- allergic reactions, most often it is urticaria.
How to treat it
- Myiasis treatment of various origins engaged therapists, infectious disease and Parasitology.
- Ultrasonic examination of affected areas can be used to determine whether insect under the skin. In complex cases, resorting to CT (CT scan) or MRT (Magnetic resonance imaging)
- biopsy (to do this, take a material with lesion area)
- Finding the location of fly larvae in the human body is possible by means of serological tests, analyzes the amount of antibodies in the blood, on the basis of what can be diagnosed - cutaneous myiasis.
- potent anti-parasitic agents - As a treatment prescribed "Ivermectin", used in medicine, special ointment. Discovered the larvae are removed surgically.
- Treatment of myiasis "ivermectin" not assigned to people with weakened immune systems, HIV, pregnant women. Breastfeeding women can resume no earlier than the baby-feeding, than a week after the last dose.
- On the possibility of the larvae were removed with sterile tweezers, Local anesthesia. When certain types of parasite infection is close to the skin surface, sometimes it is even possible to make out through the opening of the fistula.
- In case of severe necrosis development, performed surgery.
- Treatment of disease with the addition of a secondary infection is also done quickly.
- Sometimes the larvae are killed, prevents them from access of air.
- After cleansing the lesion from parasites, wound washed and disinfected.