Wolfhart fly: parasite lifestyle, pathways of infection and treatment methods for wolfarthiasis

The Diptera squad has a large family of gray meat flies, numbering about 2600 species. Its representatives are distinguished by large sizes and the method of growing larvae on vertebrate animals. Most insects breed on corpses, but the wolfarth fly gives birth to offspring in the wounds of mammals, sometimes humans. The vital activity of the larvae in the host tissues leads to a dangerous disease - wolfarthiosis. Its signs are lethargy, weight loss. Animals can die without treatment.

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Wolfhart fly (Wohlfahrtiamagnifica) - one of the species gray meat flies. Insects are synanthropic organisms whose lifestyle is closely related to humans. Body sizes of adults up to 10-14 mm. The main body color is gray. On the mesonotum there are three longitudinal stripes of black color. Black spots on the sides and in the upper part of the ovoid abdomen. The body is covered with light gray plaque and hard hairs. The head is large, large faceted eyes are dark red. Proboscis licking type. The antennae are black.

The wings are wide, transparent, well developed. At the base and along veins of smoky color. Jointed black limbs of a running type, covered with setae. Sexual dimorphism of flies is represented by the location of the eyes. Judging by the distance between the eyes, this is a female imago in the tungsten fly imago; in males it is only 2/3 of the eye width.
Larvae of the first age are small (1.5 mm) vermiform, white. After two links, by the third age it becomes thinner and larger. The body increases 10 times - up to 15 mm, becomes yellow. There are three mortal hooks on the head. Segments of the chest and abdomen are covered with brownish spines.

Information. The insect was first described by the German physician Wolfart in 1770.

Distribution area

Wohlfahrtiamagnifica is a common species. Flies live in southern Europe and Russia, the Caucasus, Central Asia, the Middle East, China and North Africa. Insects choose places near large livestock enterprises. The Wolfart fly is considered a pasture species. She settles not far from grazing areas.

Lifestyle and breeding features

Wolfhart fly refers to an insect with a complete transformation. But its life cycle is different from other dipterans. Females do not lay eggs, they mate in their body. Larvae of the first age are born. They are obligate parasites - organisms that cannot survive without a host. Larvae develop only in the tissues of vertebrates or humans. The first half of adult life is spent in the field. They feed on nectar of flowers, prefer umbrella inflorescences. Also, the Wohlfahrtiamagnifica diet includes vegetable juices, aphid secretions, liquid manure, and purulent wound secretions. In the southern regions, 25 days are enough for the development of one generation; up to six generations manage to change during the summer period.

Breeding

Flies are especially active in hot weather, often fly before the rain. Females live from 8 to 30 days, males are slightly smaller. After mating, it takes up to two weeks before the offspring ripens in the body of the fly. She feels this moment and moves closer to the barnyard.The female lays larvae in portions of 10-20 pieces, all in all, she is able to tolerate 150-20 pieces. The insect seeks to get rid of offspring as soon as possible, which begins to eat it from the inside.

Information. Females of the wolfarth fly have an excellent sense of smell; it catches the smell of a wound in an animal at a great distance.

Larva of the second age has a body length of up to 9 mm. She still has two mouth hooks that corrode the tissue. By the final third age, the larvae of the tungsten fly reach 18-20 mm. The process lasts from three to eight days. Then the parasite paves the way out and falls out of the host's body. The larva prefers to leave in the morning when the soil, heated in a day to 50-55 ° C, cools down. For pupation, it must be buried in the ground. Depending on the structure of the soil, they can be at a depth of 15 to 30 cm. Subsequently, a hard shell (puparia) forms around the pupa, which protects it from dryness and high temperature.

Attention. The larva on the hot soil (55-60 ° C) dies within 2-3 minutes.

The red-brown color of the pupa is characteristic of many representatives of the family of gray meat flies. Outwardly, it retains many features of an adult larva. The pupa has spiracles and many small respiratory openings. The duration of the stage depends on the ambient temperature. Under favorable conditions, 9 days is enough, in cool weather - 21-24 days. Pupae formed in September and October winter. In the spring, with the first warmth, young flies appear from them. They quickly recover, spread their wings and fly away in search of food.

Parasite

In temperate regions, the tungsten fly is a seasonal pest. The peak of its activity occurs in the summer months, and in the cold season it disappears. The main objects of parasitism are sheep and goats. After the hair is sheared, the animals remain scratched and cut by the pests used by the pests to enter the body. Other cattle are less likely to get sick, but cases of wolfarthiosis are found in cows, horses, and camels. Females lay larvae not only in wounds, but also on the mucous membrane of the nose, mouth, ears, eyes, genitals.

The larvae of flies, developing in the host body, cause myiasis. Having invaded a wound, they decompose tissues to bones with the help of secreted enzymes. The first 4-5 days, they feed on the surface, then go deep into the body and become invisible during external examination. Mechanical eating of the flesh causes severe pain, necrosis and gangrenous processes appear. Infected cattle noticeably lose weight, swelling forms at the site of parasite penetration. Without treatment, death is inevitable.

Wolfart's fly threatens the health of not only animals, but also people. They attack patients with purulent wounds, babies sleeping outdoors. Females lay larvae in the natural openings of humans, where they develop on the mucous membranes. Parasites affect the gums, eyes, maxillary cavity, ears. The patient has severe pain, inflammation, pus and blood. Especially dangerous is the laying of moves in the tissues before the larva leaves.

Attention. The consequences of the penetration of larvae into the mucous membranes of the ears and eyes are blindness and deafness.

Destruction methods

The fight against the parasite consists in the regular inspection of animals and the mechanical removal of the detected larvae. Wounds are washed with chloroform water at a concentration of 1: 100. Aerosol preparations are being processed: Wolfazol-D, Miazol. It is recommended that the lesions be washed with a solution of lysol or creolin. In the treatment of humans, antibacterial drugs are used, tetanus toxoid is introduced.

Preventative measures

1. To exclude wolfarthiosis in livestock, it is necessary to comply with sanitary standards of the conditions of detention.
2. Wounds received by animals must be treated on the same day.
3. Walking areas are recommended to asphalt.
4. The windows and doors of the rooms where animals are kept must be hung with nets in the summer months.
5. It is required to regularly clean the sewage canals and monitor the operation of the manure removal system.