Cestodes

Cestodes is a parasitic infection of humans and animals caused by flat worms belonging to the class of cestodes (Cestoda).

bullish tapeworm
Fig. 1. Bullish tapeworm.
pork tapeworm
Fig. 2. Rim hooks solexa pork tapeworm. On the head, visible powerful suction cups and hooks.

The class of cestodes is divided into 2 teams: lentetsy and tsepni. Cestodes are flat ribbon-like body, consisting of heads of solexa), cervical and individual segments (proglottid, Fig. 1). Scolex has the authorities commit - botei or suction Cup. In many species of cestodes scolex armed hooks (Fig. 2). From cervical there is a continuous growth in new segments. Under the covering fabric is located double layer muscles. The cestodes have the nerve, urinary and reproductive systems; power is the whole surface of the body. All cestodes human hermaphrodites: young developing segments of the male reproductive system, then there is a female. In the last segments Cana - uterus, filled with eggs. The size of different species varies from a few centimeters to a few meters. Localized Mature cestodes in the intestine and their larvae in different organs and tissues. Reproduction of cestodes with the intermediate host. The lentetsov uterus open, and faeces are eggs, Cana uterus closed, and in the environment fall Mature segments. At destruction of segments in the intestine eggs can be detected in the feces.
A person often parasitizes lentets wide, contamination which occurs when eating raw or half-cooked fish. Often meet and tsepni - bovine and swine; larvae of these cestodes develop in the muscles of cattle and pigs; human infection occurs when the use of infected and undercooked meat. For dwarf tapeworm man is both the intermediate and the final host. Larval stage Echinococcus and alveoli, contamination which occurs through dogs and wild predators, parasites in humans in the liver and other organs.
Diseases caused by sexually Mature cestodes may have no distinct clinical phenomena; however, often leads to violations of the digestive and nervous systems. When difillobotrioze (invasion lentetsom wide) is observed anemia pernicious type. Larvae of cestodes (tsistitserki, Echinococcus, alveolar) causes serious diseases, often with a fatal outcome.
Laboratory diagnosis of cestodoses is crucial and is based on the discovery in the faeces helminth eggs, pieces of their Strobel and individual segments. Echinococcosis (see), liviococcia (see), cysticercosis (see) recognize by clinical and radiological examination of the patient and production of immunological reactions.
Treatment of cestodoses intestines carry out specific antihelminthic means (fenasal, dihlosal, extract of rhizomes male fern and others). When parasitizing larval forms mainly used surgical treatment.
Prevention of cestodoses consists of a complex of sanitary-hygienic and therapeutic measures. Since most of cestodes person in the larval or adult stage parasitizes in animals needed a common medical-veterinary measures. Great importance is the improvement of human settlements and the broader sanitary-educational work among the population. According to the legislation of the USSR carcasses of cattle and pigs are subject to veterinary-sanitary examination.
Cm. also Gimenolepidoz, Depilation, Difillobotrios, Tenedos.

Cestodes is widely spread among humans, domestic and wild animals helminthic infections caused by tape-worm (class Cestoidea Rudolphi, 1808, type Plathelnimthes Schneider, 1873).
Medical value have two groups of cestodes: Cana (Cyclophyllidea Braun, 1900) and lentetsov (Pseudophyllidea Carus, 1863).
Adult cestodes have a long ribbon-like body, divided into segments (proglottid) and having on the front end of scolex (head). Scolex Cana equipped with four muscular suckers, and sometimes proboscis with hooks, which he attaches to the lining of the small intestine. Lentetsy are attached two slit impressions on the sides of solexa - motivami. Between skolekom and the first proglottids there is usually more subtle part of the neck. This growth zone cestodes; she constantly Geminate all new and new proglottid, and previously formed gradually relegated to the back. Thus, the further from solexa is the segment, so it is older. Young segments asexual; then gradually develop first male sex glands, and later women, i.e. the segments turn into a hermaphrodite. In the oldest proglottid, located in the tail end of cestodes, both male and female sex glands are the opposite development. The uterus, which started to develop in the previous segments, by this time reaches enormous size; tightly stuffed eggs, she fills the segment. The length of cestodes, parasitizing in a Mature stage in humans, ranging from 10-30 mm (Hymenolepisnana) to 10 l and more (Diphyllobothrium latum).
The complete development from egg to adult parasite in Cana is, as a rule, in two masters: young stage larvae develop in the body of the intermediate host, sexually - final (definitive). An exception is the dwarf tapeworm (N. dad), which, although it may develop an intermediate host (beetle pest flour and flour products), but usually goes through a cycle of development in the human body (see Gimenolepidoz). As a rule, people get them from each other. Lentetsy develop with two intermediate hosts, of which the second call for more.
Larvae Cana usually have a view of the bubble, to the inner shell of which is attached koleksi; this is the so-called Finns. Finn, with only one skolekom, called cysticercus. These larvae peculiar Canam (tapeworms) bovine and swine (see Tenedos). Sometimes on the inner wall Finns develops many Solakov, each of which may give rise to a parasite, this larva is called canorus. The most difficult form of Finns - Echinococcus (see Echinococcus). Larvae dwarf tapeworm not have the kind of bubble and called cysticercoids. Larva lentetsov parasitizing an intermediate host (some species of copepods), is called procercoids, additional host (fish) -plerocercoids.
People for some of cestodes is the final host, for others - intermediate. In the first case the adults cestodes parasites in the small intestine, the second - larvae of parasites in the tissues. Man is the ultimate owner for cepney bovine and pork, dwarf, rat, Tikovenko (see Gimenolepidoz, Depilation) and for lentetsov (see Difillobotrios). Often a person parasitizes in the tissues of cysticerci pork tapeworm (Cysticercus cellulosae), therefore, for this tapeworm people can be not only the final, and intermediate host. In rare cases, a person may have and additional host (so-called sparganosis).
Infecting people with tapeworm infection, tenisom and difillobotrioz associated with household habits of the population, in particular the methods of cooking meat and fish dishes. Infected people from eating raw, undercooked or syrodelnyj meat products and fish when they lack the Ambassador, as well as when the sample of raw meat. In turn, cattle and pigs invazirujutsja, with swallowing food or drink eggs caught on soil, grass, water with excrements of an infected person. When pollution of water bodies faeces patients difillobotrioz people and animals infected with the larvae of lentetsov crustaceans (Cyclops and others), and fish; predatory fish are infected larvae (plerocercoids) lentetsov, eating infested by them fish. Echinococcosis in humans is developing from eggs of helminths dissipated with the feces of animals - final masters (dogs, wolves, foxes and other).


Clinical effects in the tapeworm infection, teniate and difillobotrioze have a lot in common. Most often causes blurred expressed violations of the digestive and nervous systems, less blood. Cases requiring hospital treatment, are relatively rare. When difillobotrioze may be anaemic type pernicious because of deficiency of vitamin B12 is absorbed a lentetsom. Gimenolepidoz called dwarf tapeworm that affects mainly children, causing them, as a rule, unstable stools and abdominal pain. The disease long, often severe, sometimes gets a picture of epilepsy.
For the treatment of cestodoses caused by sexually Mature cestodes, you can use ethereal extract male fern, Akrikhin, fenasal, dichlorophen, pumpkin seeds and other
Until recently, all methods of treatment gave nalogoblozheniya results when gimenolepidoz called dwarf tapeworm. However, the recently proposed a new, effective treatment fenasalom. The main course of treatment consists of three seven-day cycles with an interval between them for 7 days. Fenasal or fenasal with dichlorophenol or extract fern. A month after the main course is one of anti-seven-day cycle.
Fenasal appointed on the first day of each cycle to children up to 3 years at a dose of 0.5 g; 3-4 years to 1 g; 5-6 years 1-1 .5 g; 7-8 years 1.5 g; 9 years and older -2, At the next 6 days each cycle of treatment the drug given in a daily dose of 0.5 g, regardless of age. The entire dose is mixed with an equal amount of sugar; mix pour 50 ml of warm water, mix thoroughly and allow the patient to drink at once on an empty stomach for a half hour before meals. On the first day of each cycle after 3-4 hours after administration fenasala prescribed a laxative. In the following days laxative not give. When assigning fenasala with dichlorophenol or extract paporotnika through 30 minutes after taking his drink
50 ml of 5% solution of baking soda and then within 10 minutes all of the dose dichlorophene or extract fern. One of these drugs give only in the first three days of each treatment cycle fenasalom. Dose dichlorophene: children 3-6 years - 0,125-0,25 g; 6-9 years - 0.3 g; 9-15 years and-0.4-0.5 g; 15 years and older and 0.5 - 1 g doses of the extract of a fern - see Gimenolepidoz.
Prevention of cestodoses - sanitation of settlements, the protection of soil and water from fecal contamination, routine detection and treatment of people and animals, infected by intestinal cestodes, health education of the population. To prevent gimenolepidoz necessary hygienic maintenance of children in institutions and at home, immediate treatment upon detection of an invasion.
The most important preventive measures against tinidazol are sanitary pet and thorough implementation of sanitary-veterinary control over the meat of slaughtered animals, which is regulated by the legislation of the USSR.
Cm. also Helminthiasis.