It is customary for human parasites to be called all living organisms at their own expense. These are bacteria, fungi, worms. Human parasites are divided into internal and external. The most unpleasant and causing the greatest amount of destruction of the body are helminths - a variety of parasitic worms.
Parasites and the human body
Creatures that parasitize the human body can be external or internal. External include:
- Mosquitoes.
- Caterpillars.
- Morrat.
- Microorganisms that cause scabies.
But there are many more creatures that prefer to be placed inside the body. This includes:
- Bacteria.
- The simplest.
- Helminte.
- Fungi.
The external and internal organization of the parasite belongs to the simplest. Due to the fact that they do not need to evolve for survival, their organization is greatly simplified.
There are many creatures that prefer to be placed inside the body. For example, they could be bacteria.
They can not survive without a host organism, as they are unable to get their food. But all multiply, almost without exception, very quickly, especially under suitable conditions. Where they do not go immediately.
They vary geographically. Some can be found everywhere, no climate is a hindrance for them. Others live exclusively in tropical countries, but in the human body they can easily be brought to others. In the body, they are also placed in different places.
Luminal parasites are content with empty parts of the body, and tissue parasites live in the tissues.
The developmental cycles of parasites, mainly helminths, are also varied. Some first develop in the soil (biohelminths), and then move into a living creature. Others must first develop in the body of every other living creature, but not of a person. Still others in an already adult condition can be transferred to another or become infected again.
It is a mistake to assume that infection can occur exclusively through dirty hands. The eggs of some helminths are valid outside the nutrient environment for six months and attach well to animal hair. Eggs also survive in a dangerous environment for them - if you cook meat or fish incorrectly, a whole flock of worms can settle inside you.
It is worth cooking the meat the wrong way, as a whole pile of worms can settle inside you.
Human endoparasites
Parasites are divided into endoparasites and ectoparasites. Endoparasites - those that live inside, ecto - outside. Endoparasites are capable of settling in almost all internal organs and tissues of the body. They are divided depending on the localization. Endoparasites are:
- Endoparasites of internal organs related to the external environment.
They are located precisely in those organs that are related to the external environment, not vice versa: the parasitic organism does not choose to "breathe". These organs include the intestines, lungs, and human urinary-reproductive system. These are amoebae, worms and parasitic flagella.
- Blood parasites.
They live in human blood. They can live in plasma, white blood cells, erythrocytes. These are trypanosomes, microfilariae or hemosporidia.
- Tissue endoparasites.
Those endoparasites who choose body tissues as their place of residence. Muscle tissue, brain, cartilage, connective tissue. Even in nerve fibers, tissue endoparasites can be established. These are the Finnish tapeworms, trypanosomes, myxosporidia, trichina and others.
Endoparasites can choose the brain as their place of residence.
The definition of the type of parasite by the place of its localization is quite arbitrary. Many species are able to migrate through various internal organs and regularly travel through the body of the host. The process of reproduction can take place in one place, and the organisms will exist directly and feed on another. The place where the parasitic creature settles and will be considered the site of its conditional localization.
Despite the simplification of many parasitic systems, their life cycle is quite complex.
Some species throughout their life need to change several hosts, which may belong to different biological species. Others are able to survive only within one species, but may seek intermediate hosts. In one person they multiply, and in another they develop and mature. With such a complex life cycle, their sexual functions have increased significantly. To survive in the body, parasites must multiply quickly and abundantly.
helminths
There are three main types of helminths, also called worms. Ajo:
- Nematodes, they are round worms.
- Cestodes, tape-shaped endoparasites.
- Trematodes, also known as currents.
Geohelminths begin their existence on earth.
Further, they can be divided according to the length of the life cycle and the number of seats crossed along the way. There are also three types:
Geohelminths
"Geo" is the earth. These worms begin their existence in the soil soil, only after the maturation stage are they able to infect a person. They do not need intermediate hosts; eggs enter the soil along with human feces. Up to the larval stage, they develop exclusively in the warm season.
Such worms include roundworms, intestinal eels, nectar, worms.
The larvae of these parasites can enter the human body through unwashed vegetables or direct contact with the soil.
Biohelminths
These are parasitic worms whose life stages go through several hosts. There may be two or more intermediate hosts, depending on the type of worm. Some parasites change only one person. Others, before finally entering the human body, use the organisms of other biological beings for development.
You can become infected through pets or through contact with other people, as well as by eating semi-raw meat. Biohelminths include bovine tapeworm, echinococcus, broadband, trichina and others.
Contagious worms
These worms do not need soil or intermediate hosts. They go through all the stages of their life cycle in an organism, placed very comfortably. The larvae are excreted directly from the human body, when they are in contact with house surfaces and other people, they spread freely.
Helminths can live in various organs and systems of the human body, migrating periodically from one part of the body to another.
The list of diseases caused by helminths is very wide. It is possible to determine which parasites live in the body and which treatment can be started only after all the necessary tests have been passed to determine the type of tests.
Round worms
The most common in the human environment are roundworms, also known as nematodes. In total, there are more than 24 thousand species of nematodes in the world.
The most common human nematodes are roundworms.
They are called round because of their shape, which is revealed if you make a cross cut. The most common human nematodes:
- Ascaris.
- Stake worms.
- Trichina.
- Vlasoglava.
Helminthic infection, known as ascariasis, begins with direct contact with worm-infected soil or by eating unwashed fruits and vegetables. The parasites begin to develop in the gut, then enter the human circulatory system, from where they go to various internal organs, heading into the oral cavity. A person, without noticing this, re-swallows an already grown parasite. They feed on undigested food waste. Ascaris waste products are extremely toxic. There is no vaccine for ascariasis; infection can only be prevented by observing the rules of personal hygiene.
Worm infection is called enterobiasis. These are small worms (5-10 mm) that attach to the intestinal walls. They feed on blood and intestinal contents. They lay their eggs under the skin, coming out of the anus while the owner sleeps. Due to itching, a person scratches the anal area, the larvae get under the skin and on the hands and can be easily transmitted to other people at home or in public places. There are no painful symptoms in enterobiasis; it is extremely problematic to detect worm infection at an early stage.
Trichinella, they are also Trichina, are round worms that choose an animal or a person as their owner.
Trichinella is a parasitic worm that infects the human body, causing the dangerous helminthic disease trichinosis.
They begin to develop in the area of muscle striated in the body, then they are redirected to the small intestine. In advanced cases of infection, there may be about 15, 000 Trichina eggs per kilogram of muscle tissue. These parasites are capable of causing a deadly disease, named for its source - trichinosis.
Whipworms are so named because of their appearance. The front of their small body is like a thread, with an esophagus placed in it.
The back is wider, the rest of the parasite’s internal organs are located in it. The worm can be up to 50 mm long. It feeds on juice and tissue fluid. Trichocephalosis causes the disease.
Tapeworms
There are about 3, 500 species of tapeworms known worldwide, also called cestodes. These flatworms have no digestive system at all and the diseases they cause are called cestodoses.
The most common cestodoses:
Cysticercosis
The disease is caused by swine tapeworm larvae, which enter through contaminated food, from dirty hands.
The disease affects the skin, bones, internal organs, brain and spinal cord. Most often, the parasites are sent to the brain (in 60% of cases of infection). It is diagnosed based on the appearance of rounded formations on the skin. The disease is treated; in case of central nervous system infection, the prognosis may be unfavorable.
Echinococcosis
It is located in the liver, lungs and many other internal organs. Echinococcus larvae excite the disease. They can develop within a person over several years.
Infection occurs through contact with animals, collection of berries and fruits, drinking contaminated water.
The course of the disease is not very obvious, it can develop over the years and turns out to be detected only by chance.
Alveococcosis
Alveococcosis is caused by the larvae of alveococcal worms. The disease is similar to echinococcosis, but is more severe. Affects the lungs and kidneys. Without treatment, the disease is likely to be fatal due to the development of liver failure.
Alveococcosis most often affects the kidneys.
Teniarinhoz
Teniarinhoz is caused by a bovine tapeworm. Parasitizes the tapeworm in the area of the human small intestine, develops over a period of 2. 5-4 months. The prognosis for treatment is often favorable. Parasites can be introduced into a person with raw or inadequately heat-treated raw meat.
Tapeworms are quite fertile. They have the most reduced residual sensitivity and no digestive system at all. Such parasites cannot develop without a host.
Fluke worms
Lightning is slander. These are flat worms, in the shape of their body resembling an elongated leaf of a tree.
Some types of trematodes can grow up to one and a half meters in size.
And they end up in the human body most often through fish or other seafood. About 7, 200 species of flu are known, 40 of which inhabit humans and cause trematodes, a serious disease caused by infection.
Most common lightning:
Liver
Distributed globally, it can exist in animals and humans. The biological life cycle is complex, the parasite changes hosts.
The most common stalk is the fissure of the liver.
Schistosoma
Schistosome larvae can penetrate the skin or mucous membranes. The life cycle is complex, they feed on blood. A female is capable of producing about 3000 eggs per day, the fertility of these parasitic worms is very high.
Other liver flushes
They cause opisthorchiasis, a helminthic disease that spreads mainly to the liver. They have a toxic effect on the human body.
The digestive system of flyworms is well developed, and with it the reproductive and secretory system.
The rest of the systems are underdeveloped. Trematodes feed on blood, skin epithelial cells, and intestinal contents. They can live almost anywhere: from the liver to the conjunctival sacs of the eyes.
Other types of endoparasites
The rest of the internal parasites are a variety of bacteria that cause dangerous diseases, and with them the simplest microorganisms. Fungi that spread inside the human body also belong to the endoparasite section.
Many beneficial and harmful microorganisms live in the human body. Some of them cause quite dangerous diseases that can lead to death. It is not always possible to immediately recognize the presence of parasitic creatures within yourself, but early diagnosis of the infection gives a better chance for a complete cure. If an invasion is suspected, it is recommended that you immediately undergo a thorough examination by a physician.