There are various parasites that live in the human body, disrupting the functioning of internal organs and the entire body as a whole. People knew about helminths in ancient times, and for the first time they and the diseases associated with them were described by Hippocrates.
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 development and reproduction they need to enter the human body.
According to the type of structure, all parasites in humans are divided into several categories:
- nematodes;
- trematodes;
- tape
Let us consider in more detail the listed types of parasites in the human body.
Characteristics of nematodes
These parasites are so-called nematodes. Externally, they resemble earthworms, but differ in sharper ends. Their sizes vary from one millimeter to 130 centimetres.
Many nematodes have a simple life cycle. After infection of the human body by roundworms, parasite eggs emerge from the intestine, invisible to the naked eye.
When released into the environment, the eggs mature and then return to the human body through dirty food, water, or dirty hands. Nematodes 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 is easily transmitted between people through shared objects. The development of these roundworms in the body creates severe discomfort in the form of itching around the anus.
- Nematodes. If massively infected, they are dangerous to your health. They are worms that reach a length of 25 cm and after maturation the larvae spread throughout the body and into the internal organs in the blood.
- Trichinella. These small roundworms are up to 5 mm long. Developing in the intestine, they lay larvae. They then enter the blood vessels and spread throughout the body.
- Filaria. They are distributed mainly in warm countries and their carriers are insects.
Parasites - trematodes
The so-called trematodes are parasites of the human body, the symptoms of which are not always clearly visible. These are flatworms up to 8 centimeters long, which have suckers on their bodies to feed the parasites.
Trematodes have a complex life cycle and change hosts multiple times. The eggs develop in bodies of water, after which they enter the body of the mollusk for metamorphosis. When the modified larvae emerge from the molluscs, they enter the body of the crustacean or fish, where they are modified again.
Flukes enter the body of their final host, which is a person, with raw or undercooked meat of cancerous species or fish.
Among the most popular trematodes are:
- Opisthorchis. People become infected with these parasites by eating lightly salted or undercooked carp or stroganina.
- Chinese stroke of luck. It affects many fish and crustaceans living in Primorye and the waters of Japan. The parasite affects 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 undercooked crabs and freshwater prawns become infected.
- Schistosomiasis. The parasites are usually found in tropical countries, and the larvae actively enter through human skin when swimming, as well as when water from a reservoir enters the mouth.
Ribbon parasites (worms)
We have almost figured out what parasites are in the human body, but there are still tapeworms, also of different types:
- Bull tapeworm. It can reach 10 meters in length and people become infected by eating beef that has undergone low-temperature treatment. Housewives sometimes get infected by testing the amount of spices or salt added to raw minced meat. 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 in size (up to 2 meters long) and can be infected by eating undercooked pork.
- Broad tapeworm. The length of this parasite varies between 6-15 meters. It is usually contracted by eating raw freshwater fish. Weakness, vomiting, nausea, abdominal pain, and other symptoms occur.
- Echinococcus. A dangerous helminth that can be contracted by dogs and cats carrying the parasite. In the human body, the larvae emerge from the eggs and are transported with the blood to the various organs, especially the liver. Subsequently, echinococcal cysts form, which are dangerous for health and require surgery.
We looked at what parasites live in the human body, but these are not all known helminths. Study the symptoms of parasite infestation and, if you find any, go to the doctor for diagnosis.