The most common causes of the spread of the disease is the consumption of low-quality meat. As soon as the market woman turns away, the tasty morsel is instantly swarmed by a hungry flock of flies, leaving their larvae on the food. Then these larvae migrate to the main dish (especially if the meat is cooked for insufficient time or at insufficient temperature).

The main danger of this disease is the ability of arthropods (flies belong to this class of insects) to penetrate the skin almost asymptomatically and lay eggs in any part of the body. Doctors are often faced with the need to eliminate insect larvae from the eyes, ears, wounds or upper layers of the epidermis.

Depending on where exactly the main part of the insect larvae is localized, the disease in humans is usually classified into several types.

Depending on the type of insect and the method of penetration into the human body, the disease is classified into:

Most often, larvae of arthropod insects enter the human body accidentally. Flies can lay larvae on household appliances, gastronomic products, clothing items. So ingestion of insect eggs occurs unconsciously. There are cases when larvae can crawl under the skin from clothing through an open wound.

Depending on the organs and tissues affected, the disease in humans (see photo) is classified into:

Depending on how deeply the fly larvae penetrate the skin, this type myiasis is divided into:

• epidermal;
• subcutaneous with a predominance of larvae in the connective tissue;
• directly subcutaneous.

More details about what cutaneous myiasis looks like can be found in the photo.

Cutaneous epidermal myiasis.

With epidermal myiasis, fly eggs penetrate only the upper layers of the skin. Most often, this phenomenon is characteristic of infection with botfly larvae. How it looks, look at the photo.

If the larvae make their way into the deeper layers of the skin and occupy areas connective tissue, one has to deal with the corresponding subcutaneous myiasis. This type of myiasis in humans is caused by the penetration of fly larvae and skin gadflies under the skin. Feature diseases - a small tumor that can change its location. Pimples that resemble boils often appear on the surface of the skin.

Cavity myiases. Formed when insect larvae penetrate into soft fabrics and body cavities with their further destruction.

And finally special kind diseases – ocular myiasis. You can see it in more detail in the photo. The best outcome for a person is if the larva of a gadfly or fly invades the conjunctival sac of the eye (the area of ​​the upper eyelid). The most dangerous case is when insect eggs are diagnosed in the eyeball.

Symptoms of the disease

In the initial stages, especially if the larvae have entered the human skin, there may be no symptoms. Subsequently, as the larva develops, small tubercles the size of a pea may form under the skin. Gradually they increase in size and take on the appearance of a local tumor. Characteristic sign The thing about having to deal with myiasis rather than any other disease is that with myiasis the tumor can move under the skin.

Symptoms may vary depending on the location of the larvae. If you have to deal with cutaneous myiasis, the appearance of a tumor may be accompanied by the formation of small pustules resembling boils.

If the larvae enter the human digestive tract (for example, when they are accidentally consumed with meat products), the course of the disease may be accompanied by symptoms characteristic of ordinary food poisoning. Nausea, vomiting, weakness, lethargy, apathy, sharp pain in the stomach, colitis - these are the most common signs of the disease. This is why it is often confused with a common eating disorder and receives inadequate treatment.

The most important danger of myiasis is the rapid progression of the disease, since the larvae very quickly take root in the victim’s body and begin to grow. On average, their sizes can vary from the size of a small pea to a tumor with a diameter of up to 5 centimeters.

If these are gadfly larvae, most often patients are treated for intestinal diseases. IN in this case we're talking about about such a type of myiasis as gastrophylosis. True, this type of disease occurs mainly in artiodactyl animals. The rate of penetration of larvae into internal organs striking - per day it can reach up to several tens of centimeters. the main objective gadfly larvae - penetration into the stomach and intestines.

If another type of gadfly (the so-called “tropical” gadfly) enters the animal’s body, abscess areas or nodes form in the skin. Their sizes also increase very quickly. Another type of disease carried by tropical flies is cordylobiosis. The clinical picture during the progression of this disease is similar to the previous case. However, in the first case the disease is called “dermatobiasis”, and in the second – “cordylobiosis”.

What to do?

In order for the larvae to leave the body on their own, special wipes are used. For them, chloroform is usually used (if we are talking about damage to the skin by larvae), rinsing agents (if we are talking about the penetration of larvae into the stomach), drugs with anthelmintic properties (if we have to deal with intestinal damage).

Summary. Myiasis is a disease of the skin or internal organs, provoked by the penetration of the larvae of various arthropod flies - house flies, meat flies, cheese flies or gadflies. The larvae develop and grow very quickly. In some cases, the speed of their movement under the skin can be up to several tens of centimeters per day. The disease must be treated with the help of means that help remove larvae from the body (various compresses), as well as anthelmintic drugs.

Human myiases arise due to the penetration of larvae and mature individuals of arthropods into the tissues and cavities of the body. Most often, the causative agents of the disease are:

• the tumbu fly, penetrating under the skin and forming peculiar tunnels there;
• sand flea, hoverfly and heteropod, capable of penetrating under the epidermis and laying eggs;
• carrion, cheese and Wohlfarth flies, infecting damaged skin and mucous membranes;
• small housefly, green, gray blowfly and Drosophila flies can infect the intestines, ears and genitourinary system;
• cavitary botfly, which affects the organs of vision;
• blowfly that settles in the respiratory system.

The most common route of infection is through damaged areas of the skin and mucous membranes. Insects can lay eggs in the eyes, ears, nose, wounds or sores. Some varieties of flies are capable of injecting their future offspring subcutaneously.

Consumption of infected food products, which have not undergone proper treatment, can also cause the development of myiases.

Fact: unlike sexually mature individuals, larvae do not respond to the influence of most chemical substances. This explains their ability long time located in the intestines, duodenum and bladder.

Classification of the disease

First of all, myiases are classified depending on the type of flies that cause the disease:

In addition, the disease caused by larvae is systematized depending on the location. There are tissue, cavity, ocular and intestinal myiasis.

Tissue myiasis: forms, symptoms, treatment

The cutaneous form of myiasis most often occurs in people living in unfavorable sanitary and hygienic conditions. The disease can be caused by the larvae of eighteen species of flies, as well as the sand flea. Insects securely attach to the skin, make tunnels in it and place their larvae there. In addition, infection can occur through open wounds and ulcers.

At the first stage of development, diagnosing the disease is extremely difficult. However, there are basic symptoms, the appearance of which requires immediate contact with a specialist:

Important! It is impossible to become infected with the cutaneous form of myiasis from a sick person. Infection occurs through contact with insects, soil infested with larvae, sand, products, or while caring for sick farm animals that have larvae on their fur.

Cochliomyasis is diagnosed by external examination, ultrasound, magnetic resonance or computed tomography. Samples are taken from the affected area for a biopsy, and a blood test is also given.

The only one safe method extraction of larvae in cutaneous myiasis is a surgical procedure. After the operation, the patient is given an antiseptic bandage and antibiotics are prescribed.

Cavitary myiasis: localization, symptoms, treatment

The cause of the development of cavitary myiasis, as a rule, is Wohlfart's fly, small housefly and housefly, sheep and bovine gadfly. In this case, the larvae can be localized in such places human body, How:

• oral cavity and gums;
• auricles and auditory canal;
• bladder and urinary tract;
• genitals.

Myiasis in the mouth is a fairly rare occurrence. The disease can occur due to neglect of personal hygiene rules, pustular formations in the mouth, increased salivation, and a decrease in the protective mechanisms of the immune system due to alcoholism and adulthood.

Please note: infection with fly larvae in young children can occur through dirty fingers that the baby constantly sucks.

Oral cochliomyasis is accompanied by the following symptoms:

• twitching gums and cheeks;
• bleeding gums increases, painful sensations appear;
• the appearance of ulcers on the mucous membrane and unpleasant odor from mouth;
• unbearable toothache when chewing solid food;
• nasal congestion;
• the appearance of allergic reactions;
• deterioration in general health, fatigue, loss of strength;
• in advanced cases, persistent fever may occur.

Infection of the genitourinary system occurs through dirty lower or bed sheets, infected with larvae.

Ocular myiasis: symptoms, treatment

Ophthalmomyasis is treated exclusively by surgery with the use of painkillers. After successful surgery, patients are prescribed rinsing with soda and boron solutions, as well as taking antibiotics, anti-inflammatory drugs and applying antibacterial ointments to the incision area.

Posterior internal ophthalmomyasis is treated with vitrectomy (removal of part or all of the vitreous humor of the eye) or photocoagulation, which leads to complete destruction of the larvae.

Intestinal myiasis: symptoms, treatment

Intestinal myiasis develops as a result of consuming foods contaminated with pathogenic organisms. In rare cases, they can enter the body through the anus: flies lay eggs in the anus, they are absorbed into the mucous membrane intestinal tract, and then penetrate the circulatory system and spread throughout the body.

The presence of pathogenic organisms in humans causes the following reactions in the body:

• frequent vomiting, nausea;
• intense, pronounced pain in the epigastric region;
• painful sensations in the peritoneum;
• the appearance of hemorrhage (bleeding, hemorrhages, bloody impurities in the stool);
• development of colitis;
• symptoms similar to typhus: fever, pale skin, impotence, loose stool, the appearance of a whitish coating on the tongue, a slowdown in heart rate, confusion.

The disease is difficult to diagnose based solely on symptoms. To confirm intestinal cochliomyasis, clinical studies of feces and vomit are performed.

Prevention

Main preventive measures myiasis are:

• compliance with basic hygiene rules;
• timely treatment of ulcerative lesions and violations of the integrity of the skin;
• protection of food products from flies;
• high-quality food processing;
• timely treatment of domestic and farm animals.

At the slightest sign of myiasis, you should consult a specialist. The disease cannot be cured on its own, and prolonged ignoring of the symptoms can lead to death.

The gadfly is an insect that closely resembles a fly. He has a short mustache and large expressive eyes that sparkle in the sun. different colors. The length of the body of the gadfly reaches twenty millimeters. The body is covered with villi - short, hard, dense and often brightly colored. The insect's head is shaped like a hemisphere. Well developed. The wings are light, transparent, dotted with small veins and wrinkles - just like those of a fly. The hind legs are slightly longer than the front legs.

The insect gadfly, whose description is so similar to that of an ordinary fly, is nevertheless very different from this annoying human neighbor. Both the size of the body and the amount of harm caused.

Life cycle of a gadfly

The gadfly is an insect that has a closed chain of transformations. IN full cycle In its development (with rare exceptions), it goes from an egg to an adult state (imago), having overcome the forms between them, first a larva, then a pupa. It takes the gadfly about a year to do everything.

At the first stage life cycle The female insect lays eggs. Ideally - on the body (or inside the body) of the animal; as a last resort - somewhere in the grass (so that the animal can swallow them along with food).

Once in favorable conditions, the eggs become larvae, which quietly mature in the warmth until the right moment, and then fall out of the animal’s body along with feces or exit through the skin.

After some time, the larva turns into a pupa, which, in turn, turns into an adult.

An interesting point: a mature insect does not need nutrition! It has enough reserves accumulated by the larva during its “residence” in the animal’s body, and then in the “hypostasis” of the pupa. True, the adult does not live long - only three to four days. Her main task is to have time to give birth to offspring, and at this point the “mission” is considered completed.

This is the “meaning of life” of the gadfly, an insect whose photo can be seen in this article.

Kinds

Depending on which part of the body their larvae live in, gadflies are divided into types. Below are the most common ones.

The gadfly is an insect that is quite common in Russia. About six species of this animal tormentor live on its territory.

Where and when should I expect to meet a gadfly?

The duration of the period of activity of gadflies depends on the climatic zone to which a particular area belongs. The longer the summer, the longer this period. In Russia it takes about three months - from June to August. When the botfly insect disappears, it’s time to prepare for the cold weather.

The gadfly is most active in dry, hot weather. In the open sun it turns into a real monster, but it does not like cloudy moisture.

The usual habitat of the gadfly is the banks of natural reservoirs, as well as forests and steppes. Often these insects choose certain areas where they accumulate a large number of females Naturally, males also fly here. Typically, such areas are areas where livestock are constantly walking or swampy areas. A person should stay away from them.

Gadfly harm

The gadfly poses the greatest danger, of course, to livestock. Once inside the animal's body, insect eggs very soon turn into voracious larvae, which simply eat up their “home” from the inside.

They absorb in exorbitant quantities nutrients, stocking them for future use, cause diseases of the gastrointestinal tract, and sometimes the death of the animal. In addition, as they grow and strive to “exit,” the larvae of some species of gadflies gnaw holes in the skin. Thus causing pain and making the skin of livestock unusable on the farm.

Scientists have long proven that cows subjected to constant attacks by gadflies produce significantly less milk than their luckier “comrades.” Annoying insects They irritate animals, cause them tension and do not allow them to eat normally - hence the low milk yield.

And gadfly bites can cause harm not only to cows, but also to humans.

Symptoms and consequences of a gadfly bite

When going outdoors on a hot summer day, you should remember what may await you there. dangerous gadfly. An insect bite on a person is not so subtle.

Usually, when “planning” to attack and approaching the intended victim, this fly buzzes very loudly and obnoxiously. So, in principle, there is a chance to brush it aside. But if the bite does occur, the following symptoms indicate it:

• a bright red spot on the skin with a diameter of one millimeter or slightly larger;
• severe burning, itching at the site of the bite and around it;
• bleeding that cannot be stopped for a long time;
• large swelling that forms some time after the bite (especially often on the face in the eye area);
• deterioration of health, symptoms of intoxication in case of numerous bites(It happens that gadflies attack in a group).

Often, after a bite, a person develops an allergy or dermatitis. And even more often, the swelling grows to enormous sizes and does not go away for several days. To prevent this from happening, you need to take appropriate measures immediately after unsuccessful contact with an insect.

First aid for a gadfly bite

If all the symptoms of a gadfly bite are present, the recommended algorithm of action is as follows:

• Rinse the affected area thoroughly with water (or soap);
• to remove dirt, you need to drop a little hydrogen peroxide into the bite site or lubricate the area with brilliant green;
• if the bite caused severe pain, you can take a painkiller;
• Without medicines the use of natural “helpers” is allowed, for example, juice squeezed from a chamomile stem will effectively relieve pain and act as an antiseptic;
• if the bite site begins to swell, it is advisable to take antihistamines to prevent the spread of infection;
• the bite site should be monitored for at least a day;
• It wouldn’t hurt to go to the doctor, because gadflies often become carriers dangerous infections, so it's better to be safe.

How to avoid meeting a gadfly and how to defeat it

Nothing is impossible in this world, and you can meet a gadfly even in the urban “jungle”. But the risk increases tenfold for those who go outdoors. Experienced travelers know how insidious the gadfly (insect) is. They also know how to fight it and protect themselves at least to a minimum. Here's what every tourist should take care of:

• about tents equipped with mosquito nets;
• about clothes of neutral colors - gadflies love bright colors;
• about wormwood, tansy, yarrow, which you can carry with you and lay around the tent;
• about chamomile, the branches of which can be thrown into the fire - such aromatic smoke will scare away gadflies.

And it is very important to remember: the gadfly is an insect (a photo of which can be seen in this article) is quite dangerous! Prevention measures should not be neglected. And if you happen to become a victim of an aggressor, then you should treat the bite very carefully. Who knows?! In this case, the old Russian proverb will come in handy: “God protects those who are careful.”

Representatives of the family of flies - gadflies - have a hemispherical, well-developed head, with bare eyes, which in females are spread wider at the back of the head than in males; There are three simple eyes. The antennae are placed in a pit on the forehead, short, segmented, with bare or half-pinnate bristles; the female has a significantly larger segment 3 than the male.

The proboscis of the American group Cuterebridae is quite large, horny, geniculate, retracted into the mouth slit and is hardly noticeable from the outside, without tentacles. The body is large, wide, with a transverse seam on the back, the hind legs are often very elongated.

Dogs become infected when they come into contact with grass in nature that contains botfly larvae. The movement of the dog in relation to the grass stimulates the larva to move towards a moving object - towards the dog. The larva will then move around the dog's body until it finds an opening under the skin.

Infection with gadfly larvae is seasonal from summer to early autumn, during the period of activity of adult gadflies.

An infestation of Cuterebra botfly larvae may present as bumps above the surface of the skin, or the dog may show signs associated with the larvae moving through the tissue. Symptoms may include respiratory signs, neurological symptoms, ophthalmological (eye) and skin symptoms.

Respiratory symptoms:

• Cough.
• Fever.
• Hesitant breathing.

Neurological symptoms:

• Dizziness.
• Loss of coordination (movement in a circle).
• Paralysis.
• Blindness.
• Constant “lying down” position.

Ophthalmology symptoms:

• Damage caused by larvae in the eyeball.

Skin symptoms:

• The location of the larva under the skin (tubercle, lump, compaction) will be raised above the skin level and has a hole so that the larva can breathe.

Causes of infection with gadfly larvae in dogs

Treatment of botfly larvae infestation in dogs

If the larva is at the end of its migratory stage and has settled in a specific location on the body, such as under the skin, eye or nose, your veterinarian will be able to remove it safely.

The disease begins to develop after the larvae of some types of flies and some other insects are introduced into the body of humans and animals. Thus, an adult lays eggs under the skin, in the eyes, ears, nose or open wounds. In rare cases, the lesion begins after swallowing a fly. For the larvae, the subcutaneous environment is fertile; in it they actively develop and grow, feeding on the tissues of the host. Myiasis develops quite quickly, and if left untreated, the disease can lead to disability and even death.

Basically, the carrier is the tumbu fly - as a rule, it lays larvae only under the skin

Insect larvae have unique adaptability. They tolerate the effects of many mild acids, alcohol, alkali and formaldehyde.

It is because of this that some individuals are able to live peacefully for several months in the human stomach.

Types of myiases

The insect can lay eggs in various places. Depending on the location on the body, myiases are usually divided into several groups.

Subcutaneous myiasis

The causative agents of superficial myiases are the larvae of meat, carrion, cheese, and house flies

Cutaneous myiasis in humans is easiest to treat in its early stages. In addition, you can avoid the appearance of ulcers and severe scars.

Intestinal

Infection with the intestinal form is always accompanied by nausea, vomiting, and severe abdominal pain. In advanced stages, internal bleeding occurs due to the movements of the larvae in the body cavity.

Urogenital

In this form, the lesion occurs in the human reproductive system. In the early stages, a process of suppuration always occurs due to the penetration of larvae into the body. In addition, severe itching and urinary retention are constantly felt. In the genitourinary form, there is a high risk of myiasis transforming into a malignant form, in which soft tissue cells are destroyed.

In this case, infection always occurs through underwear. Therefore, simple prevention and hygiene - The best way avoid illness.

Ocular (ophthalmomyasis)

Surgical removal of the larva, one of the most severe forms for humans

Nasal or nasal

Myases in the oral cavity

Ear (otomiasis)

This species is characterized by the location of fly larvae in the ear canal and on the surface of the shell. Infection occurs during sleep, both actively and through contaminated underwear. Otomiasis is dangerous due to complications - the larvae make passages from the ear to the human brain, which significantly reduces hearing and can also lead to meningitis. With this form, surgery is necessary to remove absolutely all the larvae.

Laying fly eggs in the ear is very dangerous - the larvae make passages from the ear to the human brain

List of diseases

• Hypodermatosis. Pathogens are eggs of some species of gadflies. Most often, the disease affects people living in rural areas and livestock;
• Cordylobiosis. The infection is caused by flies of the species Cordylobia anthropophaga. In the initial stages, myiasis looks like a boil or small ulcers;
• Wolfarthiosis. This is damage to body tissues by Wohlfarth fly larvae. Eggs are most often localized on the skin and mucous membranes, which often leads to necrosis;
• Gastrophilosis. Infection occurs by larvae of the gadfly species Gastrophilus equi. The disease is localized mainly in the internal organs. The medical literature describes cases of death.

Diagnosis and treatment

After identifying and analyzing the larvae, comprehensive treatment is prescribed.

• Surgical treatment is prescribed in almost all cases. This is necessary in order to completely remove insect eggs and larvae from the body;
• The affected area is treated with an antiseptic solution for a long time to eliminate inflammatory processes;
• After removing the larvae and treating the wound, a bandage with a restoring solution is applied to the infected area. If internal organs are affected, then all necessary doctor’s prescriptions are followed;
• In addition, a course of strong antibiotics is necessary to eliminate inflammatory processes and avoid complications.

Only timely treatment will help avoid the consequences of myiasis, because insect eggs develop very quickly, over time affecting an increasingly larger area and causing significant harm to the body.