Various parasites live in the human body that disrupt the functioning of internal organs and the body as a whole. People already knew about helminths in ancient times, and Hippocrates first described them and the diseases associated with them.
Today, science knows many parasites, but some of them are particularly common in the human body. They differ from each other in structure and mode of existence, but for their development and reproduction they must enter the human body.
Based on the nature of their structure, all parasites in humans are divided into several categories:
- roundworms;
- leeches;
- tape
Let's consider the listed types of parasites in the human body in more detail.
Characteristics of roundworms
These parasites are so-called nematodes. Externally they resemble earthworms, but differ in sharper ends. Their size varies between one millimeter and 130 centimeters.
Many roundworms have a simple life cycle. After the human body is infected with roundworms, parasitic eggs hatch from the intestines and are invisible to the naked eye.
When released into the environment, the eggs mature and then return to the human body via dirty food, water or dirty hands. Roundworms hatch from them and begin to actively develop.
All round parasites in the human body are divided into several subspecies, including:
- Pinworms. The most common parasite that can be easily transmitted between people through shared objects. The development of these nematodes in the body leads to severe discomfort in the form of itching in the anus area.
- Roundworms. In the event of massive infection, they are dangerous to health. These are worms that reach a length of 25 cm. After maturation, the larvae spread in the blood throughout the body and internal organs.
- Trichinae. These small roundworms are up to 5 mm long. They develop in the intestines and lay larvae. They then penetrate the blood vessels and spread throughout the body.
- Filaria. They are mainly widespread in hot countries and are transmitted by insects.
Parasites - leeches
So-called trematodes are parasites in the human body whose symptoms are not always clearly visible. These are flatworms up to 8 centimeters long that have suction cups on their bodies for feeding on parasites.
Leeches have a complex life cycle and change hosts several times. The eggs develop in water and then enter the body of the mollusk for metamorphosis. When the modified larvae hatch from the mollusks, they enter the body of crustaceans or fish, where they are modified again.
Leeches enter the body of their final host, humans, with raw or undercooked meat of carcinogenic species or fish.
The most popular trematodes include:
- Opisthorchis. Humans become infected with these parasites by consuming lightly salted or undercooked/undercooked carp fish or stroganina.
- Chinese coincidence. It affects many fish and crustaceans living in Primorye and the waters of Japan. The parasite attacks the bile and bile ducts, the pancreas and the liver.
- Paragonimiasis. It causes a dangerous disease that affects the lungs, liver, pancreas, kidneys and even the brain. People who eat uncooked freshwater crabs and crayfish become infected with it.
- Schistosomiasis. Parasites are usually found in tropical countries and the larvae actively penetrate human skin during swimming, as well as when water enters the mouth from a reservoir.
Ribbon parasites (worms)
We have almost figured out what parasites exist in the human body, but there are still tapeworms, which also come in different types:
- Bull tapeworm. It can reach 10 meters in length and people become infected with it when they eat beef that has undergone low heat treatment. Housewives sometimes become infected by testing raw minced meat for the amount of added spices or salt. After entering the body, the larva turns into saltpeter, which attaches to the intestinal wall and causes weight loss, loss of appetite, insomnia and dizziness in humans.
- Pork tapeworm. It is smaller (up to 2 meters long) and can be infected by eating poorly cooked pork.
- Wide tapeworm. The length of this parasite varies between 6 and 15 meters. Infection usually occurs through consumption of raw freshwater fish. Weakness, vomiting, nausea, abdominal pain and other symptoms occur.
- Echinococci. A dangerous helminth that can be transmitted by cats and dogs that carry the parasite. In the human body, the eggs hatch into larvae, which are transported in the blood to various organs, especially the liver. Echinococcal cysts then form, which are dangerous to health and require surgical intervention.
We have studied what parasites live in the human body, but these are not all known helminths. Examine the symptoms of a parasite infestation and, if you notice any, see a doctor for a diagnosis.