Parasitism as a form of existence arose on Earth for a very long time, starting from ancient protozoa and unicellular microorganisms.Humanity is faced with various parasites from the very beginning of its existence, but over the millennia of cohabitation, the parasites have not become “smarter” and more perfect for their ancestors.Parasites can cause irreparable harm to health, up to the development of severe disability or death.But at the mention of the word “parasite”, everyone basically think about worms, although this term is much wider.We will discuss parasites in more detail.

Parasites: Who are they?
Parasites are unicellular or multicellular organisms that live on the body of their owner or inside it (in the cavities of the body or cells).They are usually much smaller in size than predatory representatives of the fauna, have the ability to multiply quickly and survive in severe conditions.They eat at the expense of their owner, while causing him damage.By this, they differ from the symbionts - organisms living inside their owner and benefit him.
Many of the parasites, in addition to harm themselves, are also able to transmit dangerous diseases.Examples are mosquitoes that carry malaria and ticks that carry tick -borne encephalitis and borreliosis.
The sizes of parasites differ significantly - from microscopic, which can only be seen in a microscope, to worms, reaching a length of up to 10 m or more.Parasites use various resources of the owner - these are carbohydrates or proteins, fats, as well as minerals or vitamins to grow and develop.In the human body, the parasite can pass one or all stages of the life cycle - intermediate or final.The manifestations of the infected will depend on this.
Most of the parasites have microscopic sizes, they are difficult to detect.But some types of parasitic worms can form cysts in size to the child’s head or reach a length of several meters.
Varieties of parasitism
Several types of parasitism are distinguished.They depend on the habitat of the parasite in the human body:
Endoparasites.They live inside the body of the owners, typical representatives are helminths (or worms).They can live in the intestines, body cavities.Intracellular or intercellular parasites affect respectively certain body tissues.These include bacteria, fungi, viruses and protozoa.
To spread endoparasites, special conditions are needed, and sometimes carriers.Organisms that bring them to their constant habitats.For example, for malaria a carrier will be a mosquito.
Exoparasites.These organisms live on the surface of the owner’s body, eating his biological media for bites.Typical representatives are lice, fleas, mosquitoes, ticks.
Epiparasites.They parasitize on other parasites by forming super-parasitism.So, the fleas feeding on the blood of animals or humans have protozoa in the intestines - parasites living already in the body of insects themselves.

Types of human parasites
Although viruses, fungi and bacteria also harm a person in his body, they are considered separately as pathogens of infectious diseases.The true parasites of people include:
Protozoa.These are unicellular organisms that can only share the owners inside the body.Examples are a dysentery amoeba, malaria plasmodium or chlamydia.
Helminths.These are parasitic worms of different types - flat, tape, round and others.
Parasite insects.This group includes lice, fleas, ticks, mosquitoes.
How does a parasitic infection manifest?
One of the unpleasant facts is that not all parasitic infections have typical symptoms.So, if insect bites and lice are relatively simple, then it is not always possible to determine the presence of worms or protozoa without special analyzes.Sometimes manifestations resemble bronchitis or pneumonia, hormonal imbalance, allergies or food poisoning.Some parasites, upholstered in the intestines or abdominal cavity, provoke abdominal pain, hypovitaminosis or cholecystitis.Among the most typical symptoms, experts distinguish:
- Rashes on the skin, spots, bubbles, itching or bruising.
- Increasing appetite or its suppression, weight loss.
- Diarrhea and vomiting, various types of abdominal pain.
- Anemia (decrease in the level of hemoglobin or red blood cells).
- Sleep disorders - insomnia or severe drowsiness.
- Soreness of joints, muscles, skin.
- Allergic reactions that did not exist before.
- General malaise, weakness, irritability.
- Periodic temperatures up to high numbers or constant subfebrile fever.
However, these same manifestations are typical for many other, non -parasitic diseases, therefore, the diagnosis can confirm the detection of the parasite itself, its eggs or antibodies to it in the blood.
Important!Often there are no symptoms for a long time, they can occur after stress or infection, with the propagation of parasites to the “critical mass”.Meanwhile, many parasitic diseases are infectious, and a person, without suspecting it, infects others.This is especially likely if you neglect the elementary rules of hygiene.
How do parasites spread?
Depending on the type of parasite, the paths of its spread may vary.The transmission of the simplest, which live in a person’s intestines, to another person, as a rule, occurs fecal-oral route (for example, through infected food or water), with close contacts from humans to a person.The simplest, which live in the blood or tissues of people, are transmitted to other people through insects (for example, through a mosquito bite or sandy fly).
Many helminths in adulthood cannot multiply in people.People can be final masters - adults live in them, or intermediate ones - larvae live in them.Eggs or larvae are transmitted from dirty hands, infected food or water, dust particles lifted into the air.In addition, parasites can fall with infected fish, meat, and a bird where larvae propagate.
Ectoparasites - lice and scabies, are transmitted by contact by communication and close contacts with infected children or adults.Arthropods are important not only as provocateurs of diseases in themselves, but even more important as carriers of serious diseases - malaria, rash typhoid, tick -borne encephalitis, etc.
Parasitic infections cause a huge number of diseases in both tropics and subtropics, as well as in a more moderate climate.Of all parasitic diseases, malaria is the cause of most deaths in the world.About 660,000 people die annually from malaria, most of whom are small children.
How to identify parasites?
Of course, if these are pubic or head lice, scabies or pinworms that parents find in the baby’s pot - the diagnosis is already clear, you only need to be treated.But most parasites first need to be identified, determine exactly who it is, and only then to select a treatment that will be effective and safe.
Various types of laboratory tests are available today for diagnosis of parasitic diseases.The type of study that will be prescribed by the attending physician depends on your symptoms and complaints, any other diseases that you can have and your history of trips abroad or around the country.Diagnosis can be complicated, so the doctor can prescribe not only tests, but also additional procedures.A list of some frequently used tests that a doctor can be prescribed when diagnosing parasites:
Study of feces for the detection of parasites or their eggs.The analysis is used to identify parasites that cause diarrhea, liquid or watery stools, stomach cramps, flatulence and other diseases of the abdominal cavity.It is recommended to explore three or more stool samples collected on some days.
Blood tests for antibodies to parasites, urine tests, blood crops and some other tests depending on the alleged diagnosis.Some, but not all, parasitic infections can be found when analyzing your blood.However, in this case, blood will be examined for a specific parasitic infection;There is no blood test that will determine all parasitic infections.The doctor may prescribe two main types of blood tests:
Serology.This test is used to search for antibodies or antigens of parasites that are produced when the body is infected with parasite, and the immune system tries to fight the invaders.
Blood smear.This test is used to identify parasites found in the blood.Looking a smear of blood under a microscope, it is possible to diagnose parasitic diseases, such as friliatosis, malaria or babusiosis.This test is carried out by placing blood drops on the subject glass of a microscope.Then the object glass is painted and examined under a microscope.
In addition to tests, the doctor may prescribe other studies.Endoscopy is used to detect parasites that cause diarrhea, liquid or watery stools, abdominal cramps, flatulence and other symptoms from the abdominal cavity.It is used when the study of the stool does not reveal the cause of your diarrhea.During the procedure in the mouth (endoscopy) or rectum (colonoscopy), a tube with a camera and backlight is introduced so that the doctor can examine the intestines.This test is looking for parasites or other anomalies that can cause unpleasant symptoms.
X-ray pictures, magnetic resonance imaging (MRI), computed axial tomography (Kat).These tests are used to search for some parasitic diseases that can cause organs.

How to be treated?
When the accurate diagnosis is known, it is already easier to choose treatment.Almost all parasitic diseases are cured today.However, the treatment of helminthiasis is multi -stage and will take time from the patient.
At the first stage, the body should be prepared and cleaned of accumulated toxins.The patient is prescribed sorbents.Cleaning the body of toxins lasts at least five days.
At the second stage, anthelmintic agents are prescribed to the patient.It is better if the drug is selected individually for a certain type of parasite.Treatment is carried out in two courses.The first course will kill adults of helminths in the human body.After 10-14 days, adult worms will be replaced by new ones that will hatch from the layered eggs.The second course will kill new individuals.
At the third stage, the digestive tract, liver and immune system is restored.The patient is prescribed a course of sorbents, and after taking drugs that help in the digestive tract.Polyvitamins are added at the same time.
Sometimes the disease can be launched or has a special form, which requires surgical intervention.So, for example, in the presence of echinococcal cysts in the liver, kidney or lungs, only their removal will help.
The entire course of treatment, drugs and other procedures is selected by the doctor, based on the diagnosis, age and weight of the patient.