Structural features Bilaterally asymmetric - the only cavity of symmetry divides the body into left and right halves. Development occurs from three germ layers: ectoderm, endoderm and mesoderm. The third germ layer appears for the first time in the course of evolution and gives rise to the development of parenchymal cells that fill the gaps between the organs and the muscular system. Left half Right half
Structural features Body dimensions from 2-3 mm to 20 m. The body is elongated and flattened in the dorsal-abdominal direction; has a ribbon-like or leaf-like shape. The presence of developed organ systems is characteristic: muscular, digestive (absent in tape), excretory nervous and genital.
The integument of the body and the muscular system The cells of the epithelium and muscles are separate formations. The musculocutaneous sac consists of a single-layer epithelium (in aquatic forms, the epithelium has cilia) and three layers of smooth muscles: annular, longitudinal and oblique). Some representatives also have dorsal-abdominal muscles. Movement is provided by muscle contraction (flukes and tapeworms) or by cilia of the integumentary epithelium and muscle contraction (ciliary worms).
Digestive system Has two sections - front (mouth, pharynx) and middle (bowel branches). The intestine is closed blindly, the posterior part of the intestine and the anus are absent. Undigested food debris is removed by mouth. In tapeworms, the digestive system is absent (represented by individual digestive cells).
Excretory system Formed by a system of tubules, one end of which begins in the parenchyma with a stellate cell with a bundle of cilia, and the other flows into the excretory duct. The duct is united into one or two common channels, ending with excretory pores.
Nervous system. Sense organs. Consists of the supraopharyngeal ganglia and longitudinal nerve trunks that run along the body and are connected by transverse nerve bridges. Sense organs - touch and chemical sense. Free-living people have organs of touch and balance.
Hepatic flukes Hepatic flukes, usually 3 cm long and 1.3 cm wide. Hepatic flukes of the Opisthorchis order cause opisthorchiasis, symptoms of an early stage - enlargement of the liver, allergic reactions and gastrointestinal disorders; late stage symptoms - back pain, bilious colic, headaches and dizziness, insomnia. Treatment is carried out with anthelmintic, choleretic and enzyme preparations. High frequency electromagnetic radiation is also used.
Development cycle The life cycles of different genera differ. In species of the genus Fasciola, development occurs with one intermediate host (freshwater snail), and infection of the final host occurs when swallowed with water or eaten with coastal plants of the dormant stage - adolescaria. In the species of the genera Opisthorchis and Clonorchis, freshwater fish is the second intermediate host, and infection of the final host occurs when raw fish with invasive stages are eaten. In species of the genus Dicrocoelium, terrestrial lung snails and ants serve as intermediate hosts, and infection of the final host (usually a herbivore) occurs when an infected ant is eaten with grass.
Bovine tapeworm (tapeworm) It affects cattle and humans, causing teniarinhoses. Bovine tapeworm infection is especially common in equatorial Africa, Latin America, the Philippines and parts of Eastern Europe. An adult bovine tapeworm consists of more than 1000 segments and reaches 4-40 meters in length. The laying of the genital apparatus begins from about the 200th segment. The length of mature proglottids is mm, the width is 5-7 mm. The scolex (head section) is equipped with 4 suction cups without hooks (therefore unarmed). The life span of a bovine tapeworm in the human intestine, if no deworming measures are taken, is years. For a year, tapeworm produces ~ 600 million eggs, in a lifetime ~ 11 billion.
Development cycle Segments containing eggs are released from the human intestine (the main host). Together with the grass, they enter the cow's stomach (intermediate host). Six-hooked larvae emerge from the eggs, which penetrate into the blood vessels of the intestine and then into the muscles. In the muscles, the larva turns into Finns (a vial with a tapeworm head inside). When a person eats poorly processed phynose meat, the head of the tapeworm attaches to the intestinal wall and begins to produce segments.
Structural features Bilaterally asymmetric. Sizes from a few micrometers (soil) to several meters (sperm whale nematode). They have an unsegmented body with a dense cuticle. The ciliary cover is partially or completely reduced. The body is filiform, fusiform, non-segmented, round in cross section.
Digestive system Formed by the anterior, middle and posterior intestines. The anterior gut is differentiated into sections: the mouth with cuticular lips, the pharynx and the esophagus. The middle and hind gut are not divided into sections. The digestive tract ends with the anus.
Excretory system Presented by 1-2 cutaneous glands (modified protonephridia). These are large cells, from which two channels extend on the sides of the cell. At the posterior end of the body, the channels end blindly, and in the front they open into the external environment by the excretory pore.
Nervous system. Sensory organs Ladder-type nervous system. It is represented by the head nerve nodes (ganglia), the periopharyngeal nerve ring and several nerve trunks (dorsal and ventral), median transverse bridges. The sense organs are represented by the organs of touch and the chemical sense. Marine forms have light-sensitive receptors. Diagram of the ascaris nervous system: 1 - oral papillae with tactile endings and nerves innervating them, 2 - periopharyngeal nerve ring, 3 - lateral head ganglia, 4 - abdominal nerve trunk, 5 - lateral nerve trunks, 6 - circular nerves, 7 - posterior ganglion , 8 - sensitive papillae with corresponding nerves, 9 - anus, 10 - dorsal nerve trunk
Human Ascaris Ascaris are large round worms, their length can reach 40 centimeters. The organs of the gastrointestinal tract are most often affected, causing ascariasis. The preferred habitat for adults is the small intestine. Roundworm bisexual worms. Ascaris females can produce more than 200 thousand eggs per day. Fertilized eggs from the human intestine enter the soil. Larvae develop in them. Infection occurs when drinking water from open reservoirs, eating poorly washed vegetables, fruits, which have eggs with larvae. In the human body, the larva migrates: once in the intestine, it bores its walls and enters the bloodstream.
Structural features Bilateral symmetry of the body. Sizes from 0.5 mm to 3 m. The body is subdivided into the head lobe, trunk and anus. The polychaetae have a separate head with eyes, tentacles, and antennae. The body is segmented (external and internal segmentation). The body contains from 5 to 800 identical segments in the form of rings. The segments have the same external and internal structure (metamerism) and perform similar functions. The metameric structure determines a high degree of regeneration.
Body integument and muscular system The body wall is formed by the skin-muscle sac, consisting of a single-layer epithelium covered with a thin cuticle, two layers of smooth muscles (external annular and internal longitudinal) and a single-layer epithelium of the secondary body cavity. With the contraction of the annular muscles, the body of the worm becomes long and thin, with the contraction of the longitudinal muscles, it shortens and thickens.
Body cavity Secondary - whole (has epithelial vyzylka). In most, the body cavity is divided by transverse septa corresponding to the body segments. The cavity fluid is a hydroskeleton and an internal environment; it is involved in the transport of metabolic products, nutrients and reproductive products.
Digestive system Consists of three sections: anterior (mouth, muscular pharynx, esophagus, goiter), middle (tubular stomach, middle intestine) and posterior (hind intestine, anus). The glands of the esophagus and midgut secrete enzymes to digest food. Absorption occurs in the midgut.
Circulatory system Closed. There are two vessels: dorsal and abdominal, connected in each segment by annular vessels. Through the dorsal vessel, blood moves from the posterior end of the body to the anterior one, along the abdominal end from front to back. The movement of blood is carried out due to the rhythmic contractions of the walls of the dorsal vessel and the annular vessels ("heart") in the pharynx. Many have red blood.
Excretory system Metanephidial type. Metanephridia look like tubes with funnels, two in each segment. The funnel, surrounded by cilia, and the convoluted tubules are located in one segment, and the short tubule opening outward with an opening - excretory pore - is in the adjacent segment.
Nervous system. Sense organs. It is represented by the supraopharyngeal and subopharyngeal nerve nodes (ganglia), which are connected to the periopharyngeal nerve ring and the abdominal nerve chain, consisting of paired nerve nodes in each segment, connected by longitudinal and transverse nerve trunks. Polychaetae have organs of balance and vision (2-4 eyes). Most have only olfactory, tactile, and light-sensitive cells.
Reproduction and development Soil and freshwater forms are mainly hermaphodites. The sex glands only develop in certain segments. Internal insemination. The type of development is direct. Asexual reproduction is carried out by budding and fragmentation (due to regeneration). Marine representatives are dioecious. Development with metamorphosis, trochophore larva.
Rishta subcutaneous worm
There are worms that live in human blood. These include schistosomes. Their main habitat is blood vessels. However, they are able to penetrate into various organs, causing symptoms of damage to the genitourinary system, liver, and kidneys.
Some helminth larvae may be in the blood. For example, in tapeworms, this is how they spread through the body of the intermediate host. With the blood flow, the larvae migrate to various organs, where they fix and form cysts containing the heads of adult worms. The latter, when they enter the digestive tract of the final host, attach to the intestinal wall, giving rise to a sexually mature individual.
Flatworms: general characteristics
The body of flatworms is capable of performing complex and varied movements.
All flatworms have common structural features:
- The outer cover is represented by the cuticle. In free-living individuals, it is covered with cilia, the surface of the body of the worms is usually smooth.
- Several layers of muscle fibers are located under the outer cover.
- There is no body cavity.
- The digestive system has only one opening - the mouth. The intestine ends blindly. Some worms are generally devoid of digestive organs. So, tapeworms, which absorb nutrients throughout the body from the lumen of the host's intestine, do not need them.
- There is no circulatory system and no blood, as well as respiratory organs.
- The excretory system is represented by a network of tubes that permeate the entire body.
- The nervous system is primitive. There are several ganglia near the pharynx, from which nerve trunks connected by jumpers extend. The sense organs are formed only in free-living individuals and some worms at the larval stages of development.
The system that is really well developed is the reproductive system. Flatworms are hermaphrodites. Reproduction is possible with the participation of 2 individuals or by self-fertilization.
Suckers
The developmental cycle of trematodes is one of the most difficult. Miracidia emerge from eggs that enter the external environment. The latter feel comfortable in water and exist for some time as free-living organisms. The next stage is the introduction of miracidia into the first intermediate host. The larva does this using a special cutting device on the head. The mollusk usually becomes the host.
Their life cycle can take place in several hosts and is accompanied by a regular alternation
Here miracidium turns into a sporocyst, which gives rise to the next stage of the development cycle - redia. Those, in turn, are the predecessors of cercariae, which leave the intermediate host and re-enter the aquatic environment. Further, the development cycle follows one of two options. Cercariae are transformed into cysts directly in the external environment (attached to algae) or in the body of a second intermediate host (mollusk, fish, amphibian).
These are the longest worms with a transparent shell.
Infection of the final host occurs when it eats the infected organs of the intermediate. The developmental cycle ends with the attachment of the cyst head to the intestinal wall and the development of an adult worm. The latter can reach significant sizes (for example, a wide ribbon grows up to 10 m long).
Human is the ultimate host for flukes, but for tapeworms it may be intermediate.
What symptoms occur when a person is infected with a helminth? The clinic of the disease is primarily due to which organ is affected. Sexually mature worms usually live in the intestines, therefore, in the general picture of the disease, symptoms characteristic of digestive disorders prevail: nausea, gas formation, stool disturbances, and abdominal pain.
Helminths secrete waste products, which, entering the bloodstream, cause poisoning and symptoms of intoxication (fever, fatigue, and others). In addition, they are perceived by the immune system as an allergen. Therefore, helminthiases are often accompanied by symptoms of an allergic reaction (skin rash, itching).
Number of species: about 25 thousand.
Habitat: They live everywhere in humid environments, including tissues and organs of other animals.
Structure: Flatworms are the first multicellular animals in which, in the course of evolution, bilateral symmetry, three-layer structure, real organs and tissues appeared.
Bilateral(bilateral) symmetry - this means that an imaginary axis of symmetry can be drawn through the animal's body, while the right side of the body will be mirror-like to the left.
During embryonic development in three-layer animals are laid three layers of cells: outer - ectoderm, average - mesoderm, internal - endoderm... Certain organs and tissues develop from each layer:
the skin (epithelium) and the nervous system are formed from the ectoderm;
from the mesoderm - muscle and connective tissue, reproductive, excretory systems;
from the endoderm - the digestive system.
In flatworms, the body is flattened in the dorsal-abdominal direction, the body cavity is absent, the space between the internal organs is filled with mesoderm cells (parenchyma).
Digestive system includes the mouth, pharynx and cecum. Food absorption and undigested residues are excreted through the mouth. In tapeworms, the digestive system is completely absent, they absorb nutrients from the entire surface of the body, being in the intestines of the host.
Excretory organs - protonephridia... They consist of thin branching tubules, at one end of which there are fiery (ciliated) cells stellate, immersed in the parenchyma. A bundle of cilia (flickering flame) leaves inside these cells, the movement of which resembles a flickering flame (hence the name of the cells). The fiery cells capture liquid decay products from the parenchyma, and the cilia drive them into the tubule. The tubules open on the surface of the body by an excretory pore through which waste products are removed from the body.
Nervous system ladder type ( orthogon)... It is formed by a large head paired nerve node (ganglion) and six nerve trunks extending from it: two on the ventral side, two on the dorsal and two on the sides. The nerve trunks are interconnected by jumpers. Nerves extend from the ganglion and trunks to organs and skin.
Reproduction and development:
Flatworms are hermaphrodites. The sex cells mature in the sex glands (gonads). Hermaphrodite has both male glands - testes, and female - ovaries. Fertilization is internal, usually cross-fertilization, i.e. worms exchange seminal fluid.
CLASS CILIA WORM
Milk planaria, a small aquatic animal, an adult is ~ 25 mm long and ~ 6 mm wide, the body is flat, milky white. At the front end of the body are two eyes that distinguish light from darkness, as well as a pair of tentacles (chemical sense organs) needed to search for food. Planarians move, on the one hand, thanks to the work of the cilia covering their skin, on the other hand, thanks to the contraction of the muscles of the skin-muscular sac. The space between the muscles and internal organs is filled with parenchyma, in which they meet intermediate cells responsible for regeneration and asexual reproduction.
Planaria are predators that feed on small animals. The mouth is located on the ventral side, closer to the middle of the body, from it there is a muscular pharynx, from which three branches of a closed intestine depart. Having captured the victim, the planaria sucks out its contents by throat. In the intestine, digestion occurs under the action of enzymes (intestinal), intestinal cells are able to capture and digest pieces of food (intracellular digestion). Undigested food debris is removed by mouth.
Reproduction and development... Ciliates are hermaphrodites. Fertilization is cross. Fertilized eggs fall into a cocoon, which the worm lays on underwater objects. Direct development.
PUCKER CLASS
4 - sporocyst; 5 - redia; 6 - cercarium; 7 - adolescarium.
TAPE CLASS
Bovine tapeworm- tapeworm, reaches a length of 4 to 12 meters. The body includes a head with suction cups, a neck and a strobila - a tape of segments. The youngest segments are at the neck, the oldest are sacs filled with eggs, located at the posterior end, where they come off one by one.
Reproduction and development... The bovine tapeworm is hermaphrodite: in each of its segments there is one ovary and many testes. Both cross fertilization and self-fertilization are observed. The posterior segments, filled with mature eggs, open and, with feces, are removed. Cattle (intermediate host) can swallow eggs along with grass; in the stomach, microscopic larvae with six hooks emerge from the eggs, which enter the bloodstream through the intestinal wall and are carried throughout the animal's body and are carried into the muscles. Here the six-hooked larva grows and turns into finnu- a bubble, inside which there is a chain head with a neck. A person can become infected with Finns by eating undercooked or cooked meat from an infected animal. In the stomach of a person, a head comes out of the fin, which is attached to the intestinal wall. New segments bud off from the neck - the worm grows. Bovine tapeworm releases toxic substances that cause intestinal disorders and anemia in humans.
Development pork tapeworm has a similar character, its intermediate owner, in addition to a pig and a wild boar, can also be a person, then finns develop in his muscles. Development wide tape accompanied by a change of two intermediate hosts: the first is a crustacean (cyclops), the second is a fish that ate the crustacean. The ultimate host can be a human or a predator who ate the infected fish.
New concepts and terms: mesoderm, skin-muscle sac, tegument, hypodermis, reduction, protonephridia (flame cells), orthogon, strobila, ganglion, gonads, hermaphrodite, direct and indirect development, final and intermediate host, miracidium, cercaria, finna, unarmed and armed tapeworm.
Questions for consolidation.
1. Who is called the intermediate host? Final?
6. Why is it dangerous to drink raw water, swim in water bodies near grazing? Why is it necessary to wash your hands with soap and water after interacting with animals?
7. For which worms is oxygen harmful?
8. What aromorphoses led to the appearance of the Flatworm type?
Zoology lectures
Type Roundworms
Response plan:
General characteristics of Roundworms
The structure of the body of Ascaris human
Reproduction and development of Ascaris human
Roundworm classification, variety of species
The value of roundworms in nature and human life
Body integument Outside, the body is covered with a single layer of epithelium. In ciliary worms, or turbellaria, the epithelium consists of cells that carry cilia. Flukes, monogeneans, cestodes and tapeworms are deprived of ciliary epithelium for most of their life (although ciliary cells can be found in larval forms); their integuments are represented by the so-called tegument, in a number of groups bearing microvilli or chitinous hooks. The tegument-bearing flatworms belong to the Neodermata group. Flatworms can regenerate 6/7 of their body.
Musculature Under the epithelium is a muscular sac, which consists of several layers of muscle cells that are not differentiated into individual muscles (a certain differentiation is observed only in the region of the pharynx and genitals). The cells of the outer muscle layer are oriented across, the inner one - along the anteroposterior axis of the body. The outer layer is called the annular muscle layer, and the inner layer is called the longitudinal muscle layer.
Nervous system and sensory organs The nervous system is represented by nerve nodes located in the front part of the body of the worm, cerebral ganglia and nerve pillars extending from them, connected by jumpers. The sensory organs, as a rule, are represented by separate cutaneous cilia - processes of sensitive nerve cells. Some free-living representatives of the type, in the process of adaptation to habitat conditions, acquired light-sensitive pigment eyes - primitive organs of vision and organs of balance.
Structure The body is bilaterally symmetric, with clearly defined head and tail ends, somewhat flattened in the dorsoventral direction, in large representatives it is strongly flattened. The body cavity is not developed (except for some phases of the life cycle of tapeworms and flukes). The exchange of gases is carried out across the entire surface of the body; respiratory organs and blood vessels are absent.
Questions: How many flatworms are there in Russia? What are the body integuments of flatworms? What musculature? What are the senses? Briefly describe the structure of the body How do flatheads eat? How do they breathe? How do they reproduce?
Interesting facts 1. By digestion, flatworms are able to "learn". A group of scientists have made an unusual discovery regarding the abilities of flatworms. It turns out that if planar worms are first taught to pass the maze, then grind them in puree and let other worms eat it, then such worms will be able to pass this maze the first time.
Interesting facts 2. A heterosexual species of worms - schistosomes are inseparable throughout life. The female lives in the male's pocket all her life.
Interesting Facts 3. Almost all types of flatworms can turn inside out. 4. Here are some more interesting facts about flatworms. For example, flatworms are truly nearly immortal. If you cut off a very small piece from a worm, about 1/100 of a whole worm, then it is still able to recover to a whole organism.
Interesting facts 5. On the skin of some planarians living in fresh water, scientists have found nettle cells, which are very similar to the stinging cells found in coelenterates. It turns out that these cells actually previously belonged to coelenterates, which were subsequently eaten by ciliary worms. Stinging cells are not digested by worms. They enter their skin and serve as a defensive and offensive function.
L i
Flatworms, which are part of the group of bilaterally symmetric, are studied by the science of biology. Flatworms (Platyhelminthes) are not the only representatives of this group, it includes more than 90% of animals, including annelids and round worms, arthropods, molluscs, etc.
The types of flatworms are diverse and distributed throughout the world. There are about 25 thousand of them.
Scientific classification of flatworms
Flatworms belong to the kingdom of Bilateral (symmetrical on both sides) In connection with some controversy that arose when trying to divide flatworms into different groups, scientists attribute them to the paraphyletic group. It includes representatives of a small part of the descendants of the same ancestors.
The structure of the internal organs of a flatworm
The body of flatworms is elongated and flattened, without a cavity inside. That is, its entire space is filled with cells. Inside there are layers of musculature, which, together with the shell of the worm, form a musculocutaneous sac.
There are systems of internal organs:
- The digestive system is represented by the mouth and the blind (having no outlet) intestine. Nutrients enter through the mouth, and can be absorbed through the entire surface of the body.
- The nervous system consists of cerebral ganglia and nerve pillars. Some classes of flatworms have primitive organs of balance, vision.
- The excretory system consists of special tubules, but most often the excretion occurs on the entire surface of the body.
- The reproductive system is represented by both female (ovaries) and male (testicles) genitals. Flatworms are hermaphrodites.
Differences between flat and round worms
Roundworms differ from flat worms in that, in cross-section, their body has a round shape. Roundworms are also called nematodes. Possessing a bilaterally symmetrical body structure, they have developed muscles. But the main difference from flatworms is that round worms have an internal body cavity, while flat worms do not.
Variety of classes of flatworms
Table "Flatworms" clearly shows the division of the species into classes, which modern science has seven.
Class name | Habitat | Life cycle |
|
Monogeneans (flukes) | With the help of an attachment disk at the posterior end of the worm, Monogenea attaches itself to the gills of fish and the skin of amphibians and turtles | Very small, no more than 1 mm on average | Throughout its life, the worm has one owner, to which it gets in the form of a free floating larva |
Cestode | Length ranges from 2.5 to 38 cm | Larvae develop in the body of crustaceans when the eggs are swallowed. After the crustacean is eaten by aquatic vertebrates, the already adult individual easily moves from the intestines of the new host to the body cavity, where it lives and reproduces |
|
Aspidogastry | Live in the bodies of molluscs, freshwater and saltwater fish | An adult rarely reaches a size of more than 15 mm | Changes of hosts occur several times during the life cycle of the worms. |
Trematodes (flukes) | They have several owners in their entire life. The larva lives at the beginning in which it subsequently dies. It gets inside when swallowing cercariae (ready for colonization in the organs of the final host of the larva) |
||
Gyrocotylides | 2 to 20 cm | Hypothetically, the larvae first develop in the body of the intermediate host, and only then move into the fish. But due to the fact that chimeric fish are deep-sea, the hypothesis has not been experimentally confirmed |
|
Tape | The habitat of flatworms is the intestines of mammals and humans, to the wall of which they are firmly attached with the help of the head | They can reach sizes up to 10 m. | |
Ciliary | Mostly free-living worms, live in fresh and salt water, sometimes in moist soil | Body length ranges from microscopic sizes to 40 cm | A larva that looks like an adult worm emerges from the egg, living among plankton until it grows |
Ciliary worms
They are predators eating small invertebrates, arthropods and even large molluscs. They completely swallow small prey or tear off pieces from it with strong sucking movements.
The body of the worms is capable of self-regeneration. A striking representative is the planarian, in which even a small part of the body grows back into a full-fledged individual.
Flatworms in home aquariums
Helminths can be a big problem for aquarium hobbyists.
The habitat of flatworms is mostly aquatic. As flukes, flatworms can attach themselves via an attachment disk to the gills and skin of aquarium fish.
Adult worms lay eggs from which hatch larvae that live on the skin of the fish. Gradually, they crawl to the gills, where they grow, reaching puberty.
Some types of flatworms end up in the home aquarium with soil, live food. Their larvae can be on the surface of algae, on the skin of new fish inhabited in the aquarium.
- Pseudophyllidea (broad tapeworm). Infection with them can occur if raw, poorly salted fish is present in the diet. In the human small intestine, the tapeworm can live for decades, reaching a length of up to 20 m.
- Aeniarhynchus saginatus ( bovine tapeworm). The habitat of flatworms is the intestines of humans and cattle. Sucking to its walls, the helminth grows up to 10 m. The larvae can be found in other internal organs, in hard-to-reach places (brain, muscles, liver), so it is often impossible to get rid of them completely. The patient may be fatal. Infection occurs when helminth eggs enter the stomach with insufficiently thermally processed food, from dirty hands.
- Echinococcus (Echinococcus) is often found in dogs and cats, from them passing into the body to humans. Despite its small size - only 5 mm - the ability of its larvae to form Finns, paralyzing internal organs, is deadly. The larvae are able to penetrate the respiratory, bone, urinary systems. Echinococcus flatworms are often found in the brain, liver and other internal organs. A person can easily become infected with larvae excreted in the feces of a dog, which spread to the wool, and from there to all household items and food.
- The hepatic fluke is the culprit of cholecystitis, hepatic colic, disruption of the stomach and intestines, and allergies. The habitat of flatworms is mainly the liver of humans and warm-blooded animals, biliary tract. The body length of the fluke does not exceed 3 cm. The peculiarity is that not only mature individuals, but also their larvae are capable of reproduction.
Prevention of infection with helminths
Preventive measures for the entry of eggs and larvae of helminths into the human body are as follows:
- It is necessary to wash your hands thoroughly with soap and water before every meal, after visiting public places, the toilet, the street, and communicating with pets.
- Wash raw vegetables and fruits with warm water and soap.
- Do not eat raw meat and fish.
- To heat-treat food products for a long time, especially meat, fish.
- Pay attention to the timely prevention of helminthic invasions of domestic animals.
- Regularly, at least once a year, take an analysis of feces for eggs of worms.
