Throughout his life, a person is exposed to the risk of infection by various parasites. The most common are helminths (worms in humans). These parasites in the human body lead to many complications, including: disruption of the gastrointestinal tract, physical damage to internal organs and helminthiasis. Helminthiasis is not one disease, but a group of diseases caused by parasites living inside a person. All helminths are divided into 3 main types:
- nematodes (belong to the order of roundworms), prominent representatives - roundworms, pinworms, whipworms;
- tapeworms, or cestodes (an order of flatworms), are represented by tapeworms, bovine tapeworms;
- flukes, or trematodes (order of flatworms), are represented by the liver fluke.
Since helminths leave the host's body during the reproduction period in order to preserve the species, transferring to another host or into the environment, they are also distributed according to the type of transfer:
- Mechanical transfer involves movement over long distances, without any worm development occurring in the carrier's body. These include most arthropods (crustaceans, arachnids and centipedes), often carried on the legs of ordinary flies.
- An intermediate host is a specific mode of transmission in which one of the developmental stages takes place within the body of the vector. For example, for bovine tapeworm, the carrier (intermediate host) is livestock and humans are the final carrier.
Helminths also differ in their mode of transmission:
- active (contact);
- passive (food).
Contact helminths are capable of entering the human body through mucous membranes and skin (schistosomes, hookworms). Foodborne diseases are more common: they develop in a person after eating unwashed food, during contact with sick people or in case of non-compliance with personal hygiene rules.
In total, there are more than 250 species of lower worms parasitizing humans worldwide. Since the symptoms of the presence of worms in humans have different manifestations, at the slightest suspicion you should contact a specialist and get tested.
Life cycle of worms, their reproduction and development
An example of the development of helminths is the classic roundworm life cycle diagram. The eggs of the parasite are extremely resistant to harmful external influences and can remain in the soil for up to six months. The development of the larva itself requires 2 weeks to 2 months, depending on environmental conditions: temperature, humidity, oxygen availability. A ripe egg enters the stomach with food, where gastric juice eats away the egg shell, releasing the larva.
After that, the roundworm enters the bloodstream through the intestinal wall and begins to move throughout the vascular system until entering the pulmonary alveoli. The roundworm larva is aerobic, only here it becomes active and continues to develop. Feeding on blood, it reaches 3 to 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 cough in a person, as a result of which the larva, along with mucus, enters the oral cavity and then into the intestines. Here the final stage of the formation of the larva into an adult occurs.
The life cycle of an adult roundworm lasts approximately one 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 early as possible. Ascariasis is accompanied by intoxication and a complication will be intestinal obstruction, in some cases requiring urgent surgical intervention.
Reproduction of helminths occurs in 2 ways, on the basis of which worms are divided into biohelminths and geohelminths. Typically, parasite eggs end up in the external environment, where they mature. Next, the egg must enter the host, where it fully develops (geohelminths) or goes through the stage of transformation into a larva (biohelminths).
For biohelminths, the development process is more complex: the stages of development until adulthood and the attainment of maturity are separated from the stage of emergence of the larva. That is, from the external environment, the egg first enters an intermediate medium, where the larva hatches. It must then be ingested by its final host to reach its adult form. Sometimes biohelminths change up to 4 intermediate carriers before reaching their final host.
Symptoms
How to determine the presence of worms? Polymorphic symptoms and the absence of painful sensations in the early stages of the disease complicate the diagnosis. Often, the reasons for the appearance of worms in humans are associated with the consumption of stale or contaminated food, and the parasites themselves live directly in the gastrointestinal tract, so signs of their presence inthe human body are in most cases linked to the functioning of the intestines:
- loose (unstable) stools;
- pain and bloating;
- allergic skin rashes;
- flatulence;
- nausea;
- to vomit;
- lack or excess of appetite;
- at night - sleep disturbances, tremors, teeth grinding, salivation;
- itching in the anus;
- the presence of mucus or blood in the stools.
These symptoms appear after infection and last a short time (around 7 days). In the event of reinfestation, they are repeated after 2-3 weeks. In the absence of treatment or due to the occurrence of an acute or chronic form of the disease, certain symptoms do not disappear, and to this are added the consequences of a long stay of parasites in the body:
- Intoxication appears 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 greater the symptoms of poisoning - from morning sickness to vomiting and abdominal pain.
- Congestion of the lungs (infiltrates), bronchial spasms, pneumonia. The main culprits are parasites that develop in the alveoli of the lungs and damage them, causing 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.
Diagnostic
The diagnosis is made in the laboratory. Only in this case, in the presence of worm eggs and their signs in the blood or feces, can helminthiasis be diagnosed with confidence. However, stool analysis is not always enough - some types of parasites are not manifested there. A special method for determining the presence of worms is a serological blood test for antibodies. For the diagnosis of helminthiasis, the following are used:
- biliary studies;
- macroscopy (to identify roundworms and pinworms);
- muscle tissue biopsy 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 numerous destruction of organs and the central nervous system, after which they settle in muscle tissues. Parasites in human muscles gradually create a capsule of infiltrates around them and the symptoms of their presence in the body decrease, but at this stage serious damage to the health of the host has already been caused.
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 respond to the presence of smaller foreign bodies in the circulatory system. In places where parasite larvae accumulate, internal swellings 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 widespread and largely overlap with the signs of other diseases, self-diagnosis cannot be completely reliable. There are cases where, after eating bananas, people noticed dark threads in their stools, which were mistaken for worms. Before starting treatment, it is necessary to undergo all tests to determine the presence and type of parasites.
Treatment of helminthiasis
When treating parasitic diseases, several general rules must be followed:
- Thorough disinfection of the patient's linen and the room in which they are located. Reduce contact to a minimum, separate dishes.
- Strict diet excluding alcohol. It is recommended to drink carrot juice and infusion of birch buds.
- Maintain personal hygiene, frequent hand washing and laundry, cleaning of living quarters.
- Monitoring the progress of the treatment and its effectiveness.
Modern treatment methods exclude the use of a separate drug, as this does not guarantee complete coverage of all types of helminths. Most often, the doctor prescribes a drug with an initial action that weakens the parasites. After 3 days, depending on the patient's age and the severity of the infection, anthelmintic drugs are prescribed. Pregnant women or people with contraindications to medications are prescribed a non-toxic drug from the tetrahydropyrimidine group.
If it is not possible to consult a doctor, use folk remedies. The following have a good anthelmintic effect:
- enema with garlic infusion, taking garlic on an empty stomach;
- infusion of tansy on an empty stomach 4 times a day before meals;
- wormwood tincture in alcohol, taken 3 times a day, 20 mg.
Nowadays, helminth infections are diagnosed and treated in a short time. If you do not neglect the disease and start treatment on time, this will avoid complications and re-invasion. Parasitic diseases pose the greatest danger to children: there is a delay in mental development, complications arise in the form of chronic diseases and inflammatory processes. It is extremely important to quickly explain to your child the need to wash their hands and follow the rules of personal hygiene. Adults are also required to follow other preventive measures.
Helminthiasis prevention
In addition to personal hygiene, a number of factors influence the elimination of the cause of worms:
- wash vegetables and fruits with hot water;
- keep 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 heat treatment of fish and meat;
- fight against insects living in the house;
- refrain from swimming and resting in areas where cattle graze.
Compliance with preventive measures and prompt consultation with a doctor in the event of infection will help avoid complications. The correct dosage of medications prescribed by a specialist doctor will quickly eliminate parasites, and folk remedies can be used in combination with prescribed medications.