A person is exposed to the risk of infection with various parasites throughout his life. The most common are helminths (worms in humans). These parasites in the human body lead to many complications, including: gastrointestinal tract disorders, physical damage to internal organs and helminthiasis. Helminthiasis is not a single disease, but a group of diseases caused by parasites living in humans. All helminths are divided into 3 main types:
- nematodes (belonging to roundworms), prominent representatives - roundworms, pinworms, whipworms;
- tapeworms, or cestodes (an order of flatworms), represent tapeworms, beef tapeworms;
- flukes, or trematodes (an order of flatworms), are represented by the liver fluke.
Since helminths leave the body of the host during the reproduction period in order to preserve the species, moving to another host or to the environment, they are also divided according to the type of transmission:
- Mechanical transmission involves movement over long distances, until the worm develops in the body of the carrier. This includes most arthropods (crabs, spiders and centipedes), often carried on the legs of common flies.
- An intermediate host is a specific mode of transmission in which one of the developmental stages occurs in the body of the vector. For example, for bovine tapeworm, the carrier (intermediate host) is cattle, and humans are the final carriers.
Helminths also differ in the way they are transmitted:
- active (contact);
- passive (food).
Contact helminths can enter the human body through the mucous membrane and skin (schistosomes, hookworms). Diseases transmitted by food are more common, they develop in a person after eating unwashed food, during contact with sick people or non-observance of personal hygiene rules.
In total, there are more than 250 species of lower worms in the world that parasitize humans. Since the symptoms of the presence of worms in people are manifested in different ways, at the slightest suspicion you should contact a specialist and get tested.
Life cycle of worms, their reproduction and development
An example of helminth development is the classic diagram of the life cycle of a roundworm. Parasite eggs are extremely resistant to external harmful influences and can remain in the ground for up to six months. The development of the larva itself takes from 2 weeks to 2 months, depending on the environmental conditions: temperature, humidity, availability of oxygen. A mature egg with food enters the stomach, where gastric juice eats away the eggshell, releasing the larva.
After that, the roundworm enters the bloodstream through the intestinal wall and begins to move through the entire system of blood vessels until it enters the alveoli of the lungs. The roundworm larva is aerobic, only here it becomes active and continues to develop. They feed on blood, grow up to 3-4 mm in length. Having reached primary maturity 4-5 days after invasion, the roundworm begins to move towards the bronchi. Its movement causes a person to cough, as a result of which the larva, together with mucus, enters the oral cavity and again into the intestines. This is where the last stage of the larva's transformation into an adult occurs.
The life cycle of an adult roundworm lasts about a year, during which time it lays up to 250, 000 eggs. Human health, and sometimes even life, directly depends on the presence of worms in the body and their quantity, which is why it is important to start treatment as soon as possible. Ascariasis is accompanied by intoxication, and the complication will be intestinal obstruction, which in some cases requires urgent surgical intervention.
Reproduction of helminths takes place in 2 ways, based on which worms are divided into biohelminths and geohelminths. Typically, parasite eggs end up in the external environment, where they mature. Then the egg must enter the host, where it either fully develops (geohelminths) or undergoes a stage of transformation into a larva (biohelminths).
For biohelminths, the development process is more complex; the stages of development into an adult and reaching maturity are separated from the stage of larval appearance. That is, from the external environment, the egg first enters the middle carrier, where the larva hatches. It then needs to be swallowed by its final host to reach its adult form. Sometimes biohelminths change up to 4 intermediate hosts before reaching their final host.
Symptoms
How to determine the presence of worms? Polymorphic symptoms and the absence of painful sensations in the first stages of the disease make diagnosis difficult. Often the reasons for the appearance of worms in humans are related to the consumption of stale or contaminated food, and the parasites themselves live directly in the gastrointestinal tract, so the signs of their presence in the human body in most cases relate to the functioning of the intestines:
- loose (unstable) stool;
- pain and bloating;
- allergic skin rash;
- flatulence;
- nausea;
- to throw up;
- lack or excess of appetite;
- at night - sleep disorders, throwing up, teeth grinding, salivation;
- itching in the anus;
- the presence of mucus or blood in the stool.
These symptoms appear after infection and last for a short time (about 7 days). In case of reinfestation, they are repeated after 2-3 weeks. In the absence of treatment or due to the appearance of an acute or chronic form of the disease, some symptoms do not disappear, and to them are added the consequences of a long stay of parasites in the body:
- Intoxication occurs almost simultaneously with infection, but in the early stages it is not so noticeable. The greater the number of worms in the human body, the stronger the symptoms of poisoning - from morning sickness to vomiting and abdominal pain.
- Congestion in the lungs (infiltrates), bronchial spasms, pneumonia. The main culprits are parasites that develop in the alveoli of the lungs and damage them, which causes inflammatory processes.
- Inflammation of the heart muscle (myocarditis). An infectious disease, the result of the vital activity of helminths and subsequent intoxication.
- Meningoencephalitis is a dangerous inflammation of the brain and its membranes caused by bacteria and protozoa.
Different pathogens have their own manifestations and consequences, but most of the symptoms are common to all helminths.
Diagnostics
The diagnosis is made in laboratory conditions. Only in this case, with the presence of worm eggs and their signs in blood or feces, helminthiasis can be reliably diagnosed. However, stool analysis is not always enough - some types of parasites do not manifest themselves in it. A special method for determining the presence of worms is a serological blood test for antibodies. For the diagnosis of helminthiasis, the following is used:
- bile studies;
- macroscopy (to identify roundworms and pinworms);
- biopsy of muscle tissue to check for trichinosis;
- X-ray and ultrasound.
Trichinosis is a parasitic disease in which the larvae of the pathogen spread throughout the host's body, causing much destruction to the organs and the central nervous system, after which they settle in the muscle tissue. Parasites in human muscles gradually create a capsule of infiltrates around themselves, and the symptoms of their presence in the body decrease, but by then serious damage has already been done to the host's health.
One of the main symptoms can be considered eosinophilia, in which the number of eosinophils in the patient's blood increases sharply. Eosinophils are a subtype of leukocytes that react to the presence of the smallest foreign objects in the circulatory system. In places where parasite larvae accumulate, internal swelling and spots on the skin quickly appear - traces of infiltration. They also remain in sputum and lung fluid.
Since the symptoms of helminthic diseases are extensive and largely overlap with the signs of other diseases, self-diagnosis cannot be completely reliable. There are cases when people after eating bananas noticed dark threads in their stool, which they mistakenly mistook for worms. Before starting the treatment, it is necessary to undergo all tests to determine the presence and type of parasites.
Treatment of helminthiasis
When treating parasitic diseases, it is necessary to follow several general rules:
- Thorough disinfection of bed linen of the sick person and the room where he is located. Minimize contact, separate dishes.
- A strict diet that excludes alcohol. It is recommended to drink carrot juice and an infusion of birch buds.
- Maintenance of personal hygiene, frequent washing of hands and laundry, cleaning of residential premises.
- Monitoring the progress of treatment and its effectiveness.
Modern methods of treatment exclude the use of a separate drug, as this does not guarantee complete coverage of all types of helminths. Most often, the doctor prescribes an initial drug that weakens the parasites. After 3 days, depending on the age of the patient and the severity of the infection, anthelmintic drugs are prescribed. Pregnant women or people with drug contraindications are prescribed a non-toxic drug from the tetrahydropyrimidine group.
If it is not possible to see a doctor, use folk remedies. A good anthelmintic effect has:
- garlic infusion enema, taking garlic on an empty stomach;
- tansy infusion on an empty stomach 4 times a day before meals;
- wormwood tincture in alcohol, taken 20 mg 3 times a day.
Today, helminth infections are diagnosed and treated in a short time. If you do not ignore the disease and start treatment in time, it will help to avoid complications and re-invasion. Parasitic diseases are the biggest danger for children: there is a halt in mental development, complications arise in the form of chronic diseases, inflammatory processes. It is extremely important that you explain to your child as soon as possible the need to wash hands and follow the rules of personal hygiene. Adults are also required to observe other preventive measures.
Prevention of helminthiasis
In addition to personal hygiene, there are a number of factors that affect the removal of the causative agent of worms:
- washing vegetables and fruits in hot water;
- keeping the house clean, regular wet cleaning;
- a balanced diet that provides the body with a sufficient amount of vitamins of all groups;
- monitoring the condition of pets, annual visits to the veterinarian;
- proper thermal processing of fish and meat;
- fight against insects living in the house;
- refraining from swimming and resting in areas where cattle are grazing.
Compliance with preventive measures and timely consultation with a doctor in case of infection will help avoid complications. Correct dosage of medicines prescribed by a doctor will quickly get rid of parasites, and folk remedies can be used in combination with prescribed medicines.