Human parasites are represented by different groups, one of which is the protozoa. They are able to cause diseases of varying severity, and these microorganisms are not as easy to diagnose as groups with a more complex organism. For convenience, in the article they are presented in a table with the main features.
FEATURES
The simplest include organisms with a primitive organism, which combine in the film Protozoa. There are more than 15, 000 species, and some of them lead a parasitic lifestyle in the human body. They are all characterized by small size, can only be seen with a microscope and it is impossible to notice with the naked eye.
Many of the simplest parasites have an extremely primitive structure. Once in the host body, they begin to multiply. Sometimes this happens by splitting into two halves, and sometimes by multiple splits. In the latter case, the disease develops rapidly, the symptoms appear quickly, sometimes capable of eventually causing even the death of a person.
Characteristics of biology
The organism of protozoan human parasites consists of two main parts: the nucleus and the cytoplasm, in which all other organelles are located. The nucleus can be one or more.
Protozoa have the ability to form a cyst if environmental conditions become unfavorable. Because of this, they are able to stay stable for a long time, staying still and doing without nutrients. Once conditions return to normal, the cyst shell is destroyed and the microorganism resumes its normal functioning. Concentration also allows parasites to spread successfully from organism to organism.
All protozoa are divided into several categories depending on the anatomy, mode of movement and other characteristics:
- flagjela;
- Sarkodie
- sporozoaries
- ciliat.
Within each group, there are species for which humans are the intermediate or final host.
The main types
Protozoa type parasites cause many diseases and parasitize various organs. For convenience, they are presented in the table.
| Name | Infected body parts | The mode of infection | Symptoms |
|---|---|---|---|
| Balantidia | lower intestines | Eating uncooked pork or water with cysts | Balantidiasis is often associated with diarrhea. White mucus and bloody discharge appear in the feces. The mucosa of the colon ulcers and in such cases, bleeding may increase. As the disease progresses, exhaustion of a person occurs, in rare cases it can lead to death. |
| amoeba of the mouth | Oral cavity, gum pockets, dental plaque | A person becomes infected by kissing a carrier, using dirty dishes, and eating contaminated food. | Rarely affects people who do not have pathological lesions in the oral cavity. In inflammation, the oral amoeba feeds on epithelium, microbes, leukocytes, and erythrocyte cells. May cause periodontal disease. |
| dysenteric ameba | Through the bloodstream it penetrates the lungs, liver, heart, genitals, kidneys. It is located in the intestinal lumen | Ingestion with food or water | In some cases, the disease is asymptomatic. If the dysenteric amoeba attacks the intestinal walls, then the pathogenic phase begins. Characterized by colitis, tissue necrosis, liver damage, abscesses may appear. Very serious consequences cause metastases to the brain and other organs. Potential fatal outcome. Sometimes the disease gets a recurrent course. Self-healing is rare |
| Intestinal giardia | Duodenum and bile ducts. | oral route | Giardia attaches to the mucous epithelium and impairs the absorption of nutrients. Inflammation of the mucosa and persistent diarrhea develop. If the infection covers the bile ducts, yellowing of the skin appears. Some people develop immunity to intestinal Giardia, especially in countries with tropical climates. |
| Trichomonas vaginalis | In women - in the vaginal mucosa, in men - in the prostate epidermis and urethra | During sexual intercourse, as well as during birth from mother to child | Trichomoniasis is manifested by foamy discharge, itching and burning in the mucosa of the genitals, pain during sex, appearance of bloody discharge from the urethra, etc. A complication of trichomoniasis is inflammation of the vulva due to protozoan activity. cystitis, prostatitis and infertility |
| Trypanosoma brussei | Cerebrospinal fluid and brain | Once bitten by a ceci fly, which is an intermediate host | It starts with fever and swelling of the lymph nodes, continues with apathy, irresistible desire to sleep, muscle paralysis and exhaustion. If left untreated, coma and death occur. |
| Leishmania cutaneous | Contact a sick person or animal | On the skin, most often on the face or hands | The incubation period lasts from 2 months to 5 years, after which a dense brown nodule appears at the site of the insect bite. It grows, and then a purulent ulcer opens in its place. The disease lasts up to several years, and then the final scarring of the wounds occurs. Complications can be disorders of the heart, kidneys and adrenal glands. |
| Toxoplasma | Infected pets, mainly cats, sometimes infection occurs when eating protozoan food | Liver, heart, eyes, brain | In congenital form - multiple pathologies of fetal development, infant death, mental retardation, multiple infections. Acquired toxoplasmosis provokes high fever, enlarged liver, headache, vomiting, convulsions. Often takes a chronic course with added fatigue and eye damage. Rarely occurs in latent form |
| Isospora | From a person infected with fecal-oral transmission | small intestinal epithelium | The incubation period lasts about 10 days. Then the body temperature rises, vomiting and diarrhea appear. The disease is acute for a week or two, after which recovery occurs |
| Crypto sporidia | oral route | Intestinal epithelial tissue | The incubation lasts about a week, then diarrhea begins, possibly with the inclusion of spots. Stomach may ache, fever appears, signs of dehydration are possible. With insufficient immune status of the patient, the infection can affect other organs: lungs, pancreas, stomach, etc. |
Are worms the simplest
Sometimes you can hear the expression that the patient is infected with the simplest worms. It should be understood that protozoa are exclusively unicellular microorganisms, in extreme cases, organizing colonies. But they are never multicellular like worms and helminths.
In protozoa, all processes take place within the cytoplasm and cell nuclei, while in worms the anatomical organization is much more complex: they have differentiated organs that perform specific physiological functions. Therefore, it is fundamentally wrong to classify worms as protozoa.
Sometimes helminths are called the simplest parasites compared to insects: bedbugs, lice, etc. , Since the latter are much higher in evolutionary scales. In this interpretation, the name of the worm is allowed as protozoan.