Parasitic diseases caused by roundworms (nematodes), the number of affected, diversity and breadth of the spread of diseases surpass all other narazitarnye disease.They are distributed on all continents and in all climatic zones.The total number of people affected by nematodes, close to 3 billion people.
common property of all the parasites belonging to this class is fairly complicated structure of the body.
All nematodes are threadlike or fusiform body with pointed ends, not divided into separate segments (segments).The body on the cut round (hence the name).Most round of parasites capable of active movement, but more than adults, to "travel" tend to the larvae, which are often moving from one body to another host, until they reach final maturity.
Round dioecious parasites, breed or lay eggs from which the output is actively moving larva, or give birth to live larvae immediately.The larvae do not differ from the adult parasite, apart from the lack of the reproductive system.In general, the priority d
All parasites produce specific substances that protect them from the action of digestive enzymes and the host make "invisible" to the immune system.
We must understand that these parasites are highly organized organisms, to develop an effective and complex system attempts to confront a host organism to get rid of their presence.Consider the most common representatives.
From roundworms are the most common: Ascaris, pinworm, whipworm and Trichinella.Roundworms are called nematodami.Po number of diseases caused by the spread and breadth of this most numerous worms, at least in our latitudes.
Ascaris - it roundworms, the most highly organized.In addition, it is the largest representatives of roundworms.Ascaris are restless helminths: they are active, mobile and can penetrate, if they wish, in any human organ.Strunovidnoe body of Ascaris even able to drill holes in the walls of the intestines and other tubular organs.The body of a live roundworm strong and elastic.The impression is that the body wall are under high internal pressure.The body of the worm in the cross-section is round, hence the name.
person "familiar" with the roundworm since antiquity.The mention of this parasite is found in the famous papyrus Ebert (VI century BC) and in the writings of Hippocrates.The first scientific description of the parasite gave Linnaeus in 1758.How to use folk remedies in this illness, see here.
It is usually dioecious worms, with well-developed digestive and excretory channels, as well as the nervous system.Females of Ascaris can reach 30-45 cm in length, shorter than the males - 15-25 cm, and the rear end of the body is usually bent and sometimes even curled.
thickness of Ascaris an average of 6 mm.Their color can be all shades - from white to orange-red.With the death of roundworm are pale whitish color.
inside the skin and muscle of the bag has a fluid-filled body cavity.In it are the internal organs of Ascaris.
Covers ascarids are strong cuticle, not amenable to the action of digestive enzymes.This fact is an obstacle to the pharmacologic effects when attempting their expulsion.Only dead worms may be susceptible to the action of digestive enzymes and pharmacologic agents.
the front and back areas of the body are sensitive papillae, which serve as a mechanical perception.Ascaris human - geohelminthes, this means that it infests only in humans.
Adults roundworm live in the small intestine.In certain cases, can affect the liver, lungs, and also penetrate into the brain and eyes.
in the gut roundworm "foraged" ingestion of intestinal contents.Then, they are parasites.
they are fleeing, penetrate into the other tubular organs such as the cecum (the appendix) in the digestive gland ducts and so on. D. Then, already without surgery can not do under adverse conditions.
Ascaris have no organ of attachment and accessories.In this they differ greatly from the flat and tapeworms.But what keeps them and why they are not thrown together with excrement during defecation?And how can they resist the incessant peristaltic movements of the intestines?
Firstly, it is quite large worms.Dimensions help them not only well-digest food, but also to counteract the peristalsis.Kept them and because, as we have already mentioned, the body elastic and muscular activity.Ascaris retain their position, being bent into an arc, while the ends are supported in the intestinal wall.Also, to be thrown outwardly, they do anastaltic coordinated movement.Ascaris
in large quantities in a limited area normally intestine arranged in rows parallel to each other.Such strategic group parasites apparently optimal for their supply, as this roundworm partially block the intestine, allowing them longer delay their intestinal contents for nutrition and absorption of nutrients they need.
Ascaris differ enormous fecundity.Females lay up to 250 thousand. Eggs daily.It is estimated that the weight of eggs laid per female during one year of 1500 times the weight of the worm.It turns out that a person infected with Ascaris, together with the faeces allocates a huge amount of eggs.And the last feature is very thick shell that protects them from the effects of adverse environmental factors.They have almost no effect bleach and other disinfectants.
Ascaris eggs start to allocate after puberty.For the full development of eggs they require oxygen, therefore they can not develop in the human gut.Therefore, despite the huge number of eggs in the gut, infected by ascarids own impossible.
For further development they need to get out into the environment.Eggs develop into larvae, depending on the temperature and humidity in the period of from several days to several months.The optimum temperature for their development - 24-30 ° C.Human infection occurs by ingestion of mature eggs.
After swallowing and come in contact with the small intestine of these larvae, which penetrate into the intestinal wall and penetrate into the blood vessels.Hence larvae migrate from the blood to the liver and lungs (migration stage - 6-7 weeks).The larva gnaws lung alveolar wall, then turns together with sputum in the oral cavity.
Most likely, it turns out that the owner will swallow it again.Thus larva enters the intestine.And so the circle can be repeated again and again.
In 7-8 weeks after contact with human larvae reach maturity and lay eggs.We have described a circle in which it is better not to fall.Hence the conclusion: never swallow the phlegm and mucus, you can periodically spotted in his mouth.
adult Ascaris lives in the small intestine.The lifespan of the parasite for about a year.If during this time there was no reinfestation, perhaps spontaneous rid of the parasite.However, in contrast, describes cases when mass reproduction of the parasite led to the blockage of the intestine and bile ducts, bowel perforation with peritonitis and other deadly complications.Cases larvae penetrate the placenta and the fetus.
Clinical manifestations of "residence" in the body of Ascaris are very diverse.This is due to the fact that in fact we are not dealing with one type of parasite, and at least two: the adult parasite and its larvae behave in our bodies in very different ways.
source of human infection with Ascaris is the people themselves, already infested with worms.As soon as the feces of an infected person get into the environment - they have become potentially dangerous in terms of contracting.of Ascaris eggs into the soil and then into the air, carried by wind, rain and streams, etc. A little imagination -.., and the picture is clear.Home these "gifts" can bring on outdoor shoes.
After drying of Ascaris eggs have become a major component of house dust.And on the street is quite possible to breathe in the eggs of Ascaris with street dust.
Compost - a popular fertilizer applied vacationers on garden plots.Since the eggs can get on fruits and vegetables.
roundworm eggs are hardy, they can suffer long-term drop in temperature to -30 ° C.They may be in the soil in a viable state to three years.They are resistant to various chemicals, but die quickly under the action of heat.The temperature of +60 ° C kills them for 1-2 minutes, +70 ° C - for a few seconds.
Once again in the human intestine, roundworm larvae in 2,5-3 months turns into a sexually mature form.Number ascarids, both in the human gut parasites may reach several hundred.
If we talk about the features of Ascaris infestation age, children are infected more often than adults.But this is understandable, given that children are more likely to be on the street, their games are often associated with soil and sand.Hygiene skills absent in children.
disease caused by Ascaris is called ascariasis . natural immunity against ascarids in humans is not available, so the primary infection can occur quite sharply.
Allocated Ascaris waste products, which inevitably get into the human body, it is very toxic.Therefore, both the pulmonary stage of development of Ascaris, and in the intestinal phase of infection there are allergic reactions such as skin rashes, also can develop symptoms of poisoning organism.
When parasite in the intestine of Ascaris are observed various intestinal disorders caused by a mechanical action of worms in the intestines, and the action of toxins.Toxins can lead to intestinal obstruction due to intestinal spasm.Toxins ascarids depressing effect on the hematopoietic system and cause anemia, which may occur so acute that diagnosed blood cancer.
impact of toxins on the nervous system leads to various neurological disorders, such as insomnia, headaches and, in extreme cases, to a violation of muscle tone.
Even with a small number of parasites and the absence of expressed symptoms of ascariasis roundworm deplete the body, weaken the immune system, thereby aggravating for other diseases.
When mature egg roundworm enters the human digestive tract, the larva comes out of it, that needs oxygen for further development.For this purpose, it intrudes into the capillaries of the small intestine, where the liver via the portal system and the inferior vena cava into the right atrium falls.Then with blood larva penetrates into the lungs where it leaves the bloodstream and "breathe out" into the lumen of the alveoli.During the trip, the larva feeds on the blood serum first and then - red blood cells, and which eats and defecates there - ie,into our bloodstream.During this same time, it fades and grows in size almost two times.From the lumen of the alveoli the larvae climb the airway in the throat, where the newly ingested with food or saliva, and returned to the intestines.Here it is after one more turn molt into an adult parasite and the cycle repeated.The duration of travel or migration phase of 2-3 weeks.
Then begins a long cycle of parasitism friendly team of parasites in the gut with all the ensuing consequences.This intestinal phase.Each of these phases is accompanied by a picture of a specific reaction of the human organism to the parasite.
The migration phase of Ascaris larvae have a mechanical action, causing bleeding and the formation of eosinophilic infiltration in the tissues of various organs, most often in the intestine, liver and lungs, at least - in the brain, eyes and other organs (!).A young child, each of these manifestations may be fatal!
In addition, there is a stimulation of the body decay products of metabolism and larvae, leading to the development of a cough, runny nose, hives, itching, pain in muscles and joints, fever.If we join the pulmonary effects, there may be signs of pneumonia and bronchitis, asthma attacks, increase the temperature to 38 ° C or more, chills, abdominal pain, nausea, stool disorders.
When infecting a small number of larvae of this stage can proceed almost or completely invisible.
The intestinal phase are distinguished:
Except all listed in the intestinal roundworm stage behave quietly - eating, nibbling the intestinal wall and multiply.However, sometimes there is an increased tendency of adult parasites to travel.The reasons for this increased activity of several high fever, the effect of drugs or narcotics, and especially - the search for sexual partners during infection by parasites of the same sex (this happens when infecting a small number of parasites).As a result of these "migrations" may occur complications:
diagnosis migration phase of ascariasis is based on the detection of larvae in the sputum and antibodies in the blood, intestinal phase - of Ascaris eggs in faeces.But as you can see, the migration phase of the clinic may not appear at all, and intestinal not so characteristic, that doctors usually think of parasites comes, if not in the last instance, the very long.And well, if you come at all ...
While in the mouth, the larvae penetrate into the salivary ducts and glands penetrate into themselves.That is why children appear salivation, drooling after sleep are found on the pillow, perleches formed in the corners of the mouth or white patches of saliva on the lips.With long-term lesion occurs atrophy lobules glands in the infected person to suffer the taste buds and disturbed digestion, appetite is reduced or, on the contrary, increased hunger.During sleep, the mature large roundworm of baby intestine can penetrate into the stomach, esophagus, pharynx, then the larynx, the trachea and cause death by suffocation.Out of Ascaris during vomiting - a very common phenomenon.It causes anxiety and fear not only the patient, but also for others.
consequences of intestinal phase of ascarids especially dangerous for expectant mothers.Larvae of Ascaris cross the placenta and can inhabit the body of the fetus.If they take up residence in the brain of the embryo, the young mother provided a difficult birth with tears, as will increased fetal head.A further establish close contact with the pediatric neurologist, or worse, a neurosurgeon about the diagnosis "hydrocephalus" - an increase in the head, brain edema of varying degrees, until the differences of cranial bone joints.If the parasites get into the baby's lungs, is already in infancy are endless SARS, bronchitis and pneumonia, are resistant to antibiotics.Women who want to give birth to healthy children, should be previously checked for worms.
Living in the salivary glands, the larvae of Ascaris from time to time (in spring and autumn off-season, the full moon, and in the days of magnetic storms) are stepping up their activities.As a result of enhanced general intoxication of the organism, and infected, especially children, become irritable, moody, they have disturbed sleep.In the dream, man shudders, groans, grinds his teeth, with the age of these symptoms can be added to snoring.Once in the nasal cavity, the larvae can crawl in the sinuses and cause both acute and chronic inflammation of the mucous membrane.
There is a direct way for the penetration of larvae on the Eustachian tube from the nasopharynx into the cavity of the middle ear: right, left or both.l.