Linguatulidoses (linguatulidoses) - the invasion of humans and animals by arthropods of the order Linguatulida (reed), Arachnoidea class (arachnid). There are linguatulosis and porocephalosis.
Linguatulosis (linguatulosis). The causative agent is Linguatula serrata. The body of the parasite is lanceolate; the female is 80–130 mm long and up to 8–10 mm wide; the male is 18–20 mm long and up to 3 mm wide (Fig. 1, 2 and 3). In the stage of puberty, it parasitizes the nose, and frontal sinuses of the dog, wolf, fox, horse, causing rhinitis and frontal sinusitis. In the larvae stage it parasitizes a person, a hare, a rabbit, cattle and small ruminants, and a guinea pig. With secretions from the nose of the final owners (dogs, etc.), the eggs of the lingvatoula are released into the external environment. Infection occurs when swallowed these eggs with contaminated food. Diseases recorded in all parts of the world.
Fig. 1 - 3. Linguatula serrata. Fig. 1. The female. Fig. 2. Larvae of Linguatula serrata: a - larva developing in the egg; b - embryo with two pairs of limbs with hooks; c - larva of rabbit liver; d - 9 weeks old larva (1 - nerve ganglion, 2 - digestive tube, 3 - skin glands, 4 - mouth, 5 - anus, 6 - gonad). Fig. 3. Mature larva that can infect a dog (1 - mouth, 2 - two pairs of hooks - leg rudiments, 3 - gut, 4 - anus). Fig. 4 and 5. Porocephalus armillatus. Fig. 4. The female. Fig. 5. Larvae encapsulated under serous cover.
Fig. 6. Many nymphs P. armillatus in the wall of the descending colon.
The pathogenesis and clinical presentation of linguatulosis is very poorly studied. In the stomach, the larvae hatch from the ligated eggs that are swallowed, which pass through the wall of the digestive tract into the abdominal cavity and from there penetrate into the liver, lungs and other organs where they are encapsulated. After several molting, they turn into migrating larvae, invading various organs and body cavities. Usually, linguatulosis is subclinical, but sometimes bleeding occurs in the lungs. Lifetime diagnosis has not been studied; the disease is detected when opening the corpses. The treatment is unknown. Prevention - thorough washing and scalding of vegetables and fruits with boiling water.
Porocephalosis (porocephalosis). The causative agent is Porocephalus (Armillifer) armillatus. The body of the parasite is yellowish, with constrictions; the female is 90–120 mm, the male is 30–50 mm long (Fig. 4 and 5). At the stage of puberty, it parasitizes in the airways of large African snakes (python, etc.), which are the ultimate owners of the parasite. Intermediate owners - man, monkey, giraffe, antelope, hedgehog, white rat. Infection of humans and other intermediate hosts occurs through food contaminated with snakes secreting parasite eggs. It is not excluded the possibility of infection and by eating meat from invaded snakes. The disease is common in several African countries.
The clinic of porocephalosis is poorly studied. In some cases, it proceeds subclinically, sometimes a severe form of the disease develops. The occurrence of bronchitis, pneumonia, meningitis, obstructive jaundice caused by the accumulation of larval forms (nymphs) of the parasite in the common bile duct, intestinal obstruction as a result of massive invasion of its wall by nymphs of the parasite is described (Fig. 6). Recognition of porocephalosis in life is possible only after calcification of the parasite nymphs. When X-ray examination, they are noticeable in the form of double-circuit formations resembling chain links broken at one pole. The treatment is not developed.