Symptoms, diagnosis and treatment of the most common helminthiasis in humans

In this article, we will try to understand what symptoms are more often observed in helminthiasis in adults, whether they can be asymptomatic, and also what types of helminthiasis are more common in our country.

Introduction to terminology

Helminth infections in humans are usually caused by parasitic worms belonging to three classes: Nematoda (nematodes) - roundworms, Cestoda (cestodes) - tapeworms, Trematoda (trematodes) - dark worms.According to the pathogenic class, all human helminthiasis are conventionally divided into:

1. Nematodes are helminth infections associated with infection with roundworms or their larvae.The most famous nematodes are enterobiosis, ascariasis, garkiliosis disease, toxocarosis and strongyloidosis.
2. Cestoids are caused by parasitism of tapeworms or their larval forms.The most common cestodiasis are diphyllobothriasis, taeniasis and teniarynchiasis, hymenolepiasis and echinococcosis.
3. Trematodes are helminth infections, caused by various types of flukes.The most common diseases in our country are opisthorchosis, clonorchosis, less common fascioliosis and very rarely paragonimiasis.

In relation to the territory of our country, all helminthiasis can be divided into the following:

1. Typical, that is, it is often found among the population of our country;
2. Exoticism is caused by population migration and tourism to other countries.

Detection and treatment of exotic helminth infections is a more complex and time-consuming process, as laboratories may not have the necessary reagents to perform laboratory tests.The following types of helminth infestation are typical for the territory of our country.

Which population groups are more susceptible to infection?

Helminthic infections occur more often in the following groups:

1. Young children due to active knowledge of the world and lack of personal hygiene skills.
2. Children organized in groups (kindergartens, schools, camps, sanatoriums, etc.).Close interaction, shared habitat and toy exchange contribute to the spread of geohelminthiasis with a simple life cycle.
3. Adults who work closely with children, including teachers and parents.
4. People with certain dietary habits: raw or undercooked meat, fish, seafood, greens, etc.consumption.Great importance is attached to national cuisine (sushi, stroganina, yukola, porsa and other dishes), drying, salting and smoking.
5. People living in endemic areas, tropics and subtropics.
6. People living in poor sanitation without access to quality water supplies and sanitation.
7. People who live close to animals, who are closely related to agriculture and animal husbandry.

When and who should be examined?

Depending on belonging to risk groups and the characteristics of the course of helminthic infestations, examination of helminthiasis should be carried out in the following cases:

1. Children, organized and unorganized, at least once a year in the absence of any symptoms.
2. Adults who work with children and in catering establishments, doctors, sellers of children's goods and food products.
3. Children and adults entering educational institutions, sanatoriums, hospitals, boarding houses, hospices and other institutions that ensure the presence of a large number of people in one area.
4. Children and adults with skin and bronchopulmonary allergic diseases are resistant to traditional methods of therapy and elimination diet.
5. Children and adults with signs of chronic damage to the gastrointestinal tract: nausea, vomiting, diffuse abdominal pain, diarrhea, pain in the epigastric and umbilical regions, malabsorption syndrome.
6. Children and adults with signs of damage to the hepatobiliary system - hepatosplenomegaly, jaundice, pain in the right hypochondrium, AST, ALT, GGTP, increased alkaline phosphatase, portal hypertension.
7. Children and adults with prolonged low-grade fever of unknown etiology.
8. Children and adults with severe asthenic syndrome: frequent headaches, weight loss, bulimia or loss of appetite, unmotivated weakness, fatigue, sleep disturbances.
9. Children and adults with microcytic and normocytic anemia resistant to conventional treatment.B12 deficiency anemia accompanies 2-4% of cases of diphyllobothriasis, less often teniarynchiasis, ascariasis and other helminthiasis.

Features of the course of helminthic infestations

The course of any helminthic infection can be divided into several periods:

1. Infection and its clinical manifestations.Most of the helminth infections have no symptoms of infection, but with strongyloidosis, hookworm and some others, the so-called cercarioses occur - diseases caused by the penetration of the larvae into the skin.
2. The incubation period is the time from the moment of infection to the first clinical manifestations.
3. The acute stage, which most often causes the migration of larvae in the human body, their molting, maturation into sexual adults, the first laying of eggs and the first meeting with antigens unknown to the human body.The duration of the acute phase usually varies from a few days to several weeks.Sometimes the acute phase is absent or weakly expressed, which is more often observed in local people with a low degree of invasiveness or "immune memory".
4. The chronic stage occurs in the absence of treatment or its ineffectiveness and is associated with the direct influence of sexually mature individuals.

The duration of infestation depends on the life of helminths and the possibility of self-infection.

In this regard, the course of all helminthiasis can be presented in the form of several main schemes.

1. Scheme 1: the course of the disease has a sinusoidal form.Initiation (moment of infection) - increase of symptoms to a certain level (severity) - transition to chronic phase with periodic exacerbation.This type of course is typical for opisthorchosis, clonorchosis, fascioliasis and strongyloidosis.
2. Scheme 2: the course of helminthosis has a plateau shape.Infection with a subsequent increase in symptoms up to a certain point, after which the patient notes that the symptoms remain stable or decrease and disappear.A similar course is characteristic of many invasions: trichinosis, taeniasis, diphyllobothriasis, ascariasis.
3. Scheme 3: the course of helminthiasis is characterized by a continuous increase in symptoms, which can eventually lead to the death of the patient.These are, as a rule, massive infestations or helminthiasis that occur with spread against the background of immunodeficiency (disseminated strongyloidosis).

Next, let's see where worms live in the human body.Helminth infections can affect any human body, but several main "favorite" localizations in the body of the host can be identified for systematization:

1. The intestine is home to many human worms, such as roundworms, roundworms, whipworms, corn worms, beef and pork tapeworms, etc.is the most logical place of residence forHere, the parasite attaches to the intestinal wall by one of the ways and carries out its "sabotage" activity, in most cases it steals nutrients.
2. The liver and bile ducts are a favorite habitat of opisthorchids, clonorchids and fasciolae.Also, the liver is often affected during the migration of helminth larvae, for example, lung fluke, exinococcus, etc.
3. Lungs and bronchi.The life cycle of many nematodes (ascarids, roundworms, intestinal eels) cannot continue without the migration of larvae through the bronchopulmonary system.For other helminths, the lungs are the final destination and habitat of adults (paragonimiasis).
4. Central nervous system.It is most often affected by cysticercosis, echinococcosis, toxocarosis, paragonimiasis and other infections.This is usually due to the migration of larval forms and their spread through the bloodstream.
5. The skin, as a rule, becomes the habitat of larval forms, as well as various filaria.
6. Eyes - filariasis, toxocariasis.
7. Venous plexuses of the bladder, uterus and intestines in schistosomiasis.

Symptoms of helminthiasis

In general, the clinical picture of helminthic infections consists of the following syndromes:

1. Toxic-allergic.The main reasons for the development of allergic and toxic reactions are the metabolic products of adults and larval forms and the release of toxins by them.In humans, worms can cause skin rashes such as urticaria, allergic and atopic dermatitis, and sometimes eczema.Rashes have a recurring course and are difficult to respond to conventional treatment.
2. Dyspeptic.Dyspeptic symptoms include nausea, vomiting, heartburn, belching, bitterness in the mouth, and flatulence.Diarrhea or loose stools are common without increasing the frequency of bowel movements.Dyspepsia is mostly characteristic of intestinal helminths (ascariasis, trichuriasis, etc.), rarely occurs with tissue helminthosis (echinococcosis, cysticercosis, toxocariasis, etc.).
3. Indigestion and malabsorption syndrome.It is also more typical for intestinal infections, especially those where adult parasites live in the small intestine and duodenum (teniasis, diphyllobothriasis, etc.).
4. Abdominal pain: in children - more often diffuse, in the umbilical region, in the right iliac region, simulating appendicitis.The localization of pain in adults is more specific.Sometimes the pain syndrome due to helminthic infections can imitate "acute abdomen".
5. Bronchopulmonary.It is most often caused by the migration of parasite larvae to the alveoli, and then to the bronchial tree, trachea and oropharynx.The main symptoms of this phase are cough usually accompanied by productive, mucous or mucous-purulent sputum, the appearance of wet and dry wheezing, the change of breathing in a harsh or harsh form with prolonged exhalation.Loeffler's syndrome can be observed with such invasions (ascaridosis, strongyloidosis, hookworm disease).In some invasions (for example, paragonimiasis), the lungs are the usual habitat of adults.In this case, the clinical manifestations are different.Chronic cough with sputum and blood, radiological changes such as hemoptysis, pneumofibrosis, cystic lesions of the lung tissue often imitate the picture of pulmonary tuberculosis.
6. In humans, worms can cause anemia syndrome.The development of anemia can occur as a result of direct consumption of the host's blood (ankylis), theft of the host (ascariasis, taeniasis, diphyllobothriasis, etc.), stomach and intestinal dysfunction (teniarinosis, taeniasis, etc.), exposure to toxins.Anemia is mostly due to microcytic iron deficiency, and in some helminthiasis, macrocytic and B-12 deficiency.
7. Asthenia, as a sign of the presence of worms in the human body, is characterized by sleep disorders, dyssomnia, increased irritability, aggressiveness, increased fatigue, hyperactivity and lack of attention in children.It is difficult for the patient to focus on work and concentrate.An infected person may have unexplained weight loss, loss of appetite (or vice versa, increased appetite).
8. Intoxication-inflammatory syndrome manifests itself in the form of an increase in temperature up to 38 degrees and above, myalgia and arthralgia, leukocytosis and an increase in ESR in CBC.The degree of its severity depends on the immune status of the patient and the stage of invasion.The acute phase occurs more often than the chronic phase with fever and a flu-like condition.The chronic stage is characterized mostly by low-grade fever or normal body temperature.
9. In humans, worms are often the cause of unexplained asymptomatic eosinophilia.Eosinophilia is most characteristic of nematodes and trematodes and may be accompanied by generalized leukocytosis.

In the table below, we tried to summarize the available information about the symptoms of worm infection accompanying the most common helminthic infestations in humans.

Helminthoses	Symptoms of infection	Incubation period	Acute phase	Chronic stage
Enterobiosis	no	10-15 days	Perianal itching, diffuse abdominal pain, rarely diarrhea, nausea, vomiting.Insomnia, night screams and crying in children.Persistent vulvovaginitis, synechiae of the lips. The total duration of the infestation is about one or two months (if there is no re-infection).
ascariasis	no	About a week	The acute phase of up to 2 weeks is caused by larval migration.Symptoms during this period are fever, muscle and joint pain, skin rash and itching, signs of bronchitis or pneumonia (eosinophilic infiltrative changes in lung tissue).Bronchoobstruction may occur.	Loss of appetite, nausea, vomiting, abdominal pain (near the navel, right iliac region), rumbling and bloating in the intestines.Symptoms of asthenia are constant headaches, weakness, fatigue.Symptoms of anemia and hypovitaminosis.The total duration of infection (in the absence of re-infection) - 1 year
Trichocephalosis	no	1-1.5 months	Pain along the large intestine, in the right iliac region, nausea, vomiting, salivation, flatulence, stool instability, presence of blood and mucus in the stool (the total duration of invasion is up to 5-7 years).
Diphyllobothriasis	no	It is removed because the clinical picture of the invasion develops gradually	There is no such acute stage.Symptoms occur and progress slowly.General asthenia, skin rash, diffuse abdominal pain, sometimes in the right iliac region, nausea, vomiting, loss of appetite and progressive weight loss, stool instability, signs of anemia, glossitis, hepatosplenomegaly, neurological symptoms (paresthesia, impaired motor function, sensitivity, etc.) The duration of the invasion is up to 10 years or more.
Taeniasis and teniarynchosis	no	It is removed because the clinical picture of the invasion develops gradually	There is no such acute stage.The following symptoms appear and increase: weakness, fatigue, headaches and other symptoms of asthenia, mild or moderate anemia, diffuse abdominal pain and discomfort, bulimia or anorexia, progressive weight loss, leakage, nausea, vomiting, urticaria-like rashes, rarely damage to the nervous system, semi-epilepsy syndrome.
Opisthorchosis	no	2-4 weeks	Increase in temperature, weakness, fatigue, eosinophilia and leukocytosis, abdominal and liver pain, loose stool, allergic rash, hepatosplenomegaly, jaundice.	Intestinal and hepatobiliary dyspepsia, hepatomegaly, jaundice, symptoms of pain in the liver, biliary colic, girdle pain (pancreatitis), gradual increase in liver failure may occur.
Clonorchosis	no	2-3 weeks	Same as opisthorchosis, but more pronounced	As for opisthorchosis.There is a high probability of developing cirrhosis and cholangiocarcinoma
Red worm and necatoriasis	2-3 days after infection, a papular or urticarial pruritic rash appears at the site of larval penetration, often resembling curved passages.The duration of this period is up to 1.5 - 2 weeks.	Actually no	About 2-4 weeks, depending on larval migration.Fever, skin rash, signs of bronchitis, bronchopneumonia - productive cough, wet, dry wheezing, sometimes bronchial obstruction.The formation of volatile eosinophilic infiltrates in the lung tissue (Leffler's syndrome) is characteristic.	The most important clinical symptom is moderate to severe iron deficiency anemia.The second important criterion is hypoalbuminemia, edema syndrome.Nausea, vomiting, epigastric pain, flatulence, fatigue, headache, general asthenia.The total duration of the invasion is up to 20 years.
Hymenolepiasis	no	It is indirectly stated that 2-3 weeks are enough for an adult to grow from a larva.	Thus, the acute stage is not pronounced;symptoms increase and are characterized by nausea, vomiting, salivation, diffuse abdominal pain, and loose stools.Damage to the nervous system in the form of headache, dizziness, fainting.Allergic manifestations - exanthema type rash, urticaria, Quincke's edema, allergic rhinitis.Pale skin with an icteric color.Body temperature is often normal.
Fascioliasis	no	1-8 weeks	Fever, liver and epigastric pain, jaundice, hepatomegaly, loose stools, allergic rash, eosinophilia and leukocytosis	Hepatomegaly, pain in the liver, hepatobiliary dyspepsia, increased liver failure, secondary cholecystitis and pancreatitis
Strongyloidiasis	On the 1st-2nd day, mild itching and papular rash appear at the site of penetration of the larvae, which quickly disappear.	Actually no	On the 3rd-4th day after infection, fever, myalgia, pain in the joints, cough with phlegm, moist and dry wheezing occur, bronchial obstruction is possible.Roentgenography reveals volatile eosinophilic infiltrates (Leffler's syndrome).An allergic rash often appears on the skin.	Pain in the epigastric, periumbilical regions, less often in the liver, belching, heartburn, nausea, vomiting, loss of appetite and weight loss, biliary dyspepsia, diarrhea (usually enteritis type, impurities in the stool are rare, usually massively invasive), hepatomegaly, jaundice.Due to regular self-infection, the infestation continues for years.
Trichinosis	Abdominal pain, nausea, vomiting, diarrhea may occur	From 1-2 days to 4-5 weeks, on average 10-25 days	After infection, first the intestinal phase begins - abdominal pain, nausea, diarrhea, then generalized - severe muscle pain, swelling of the eyelids, face, less often the trunk, rashes depending on the type. exanthema, hemorrhagic in severe cases, high fever (sometimes low grade) for several weeks.	Encapsulation of larvae and retention in skeletal muscle for 10 years or more.
Paragonimiasis	no	2-3 weeks, can be reduced to a few days	Abdominal pain, acute abdominal pain, diarrhea.Gastroenterological symptoms are replaced by symptoms of damage to the bronchi and lung tissue - cough with phlegm, chest pain, pneumonia, exudative pleurisy.	Fever or prolonged low-grade fever, prolonged cough with sputum and blood, hemoptysis, chest pain, dyspnea, weight loss, pulmonary fibrosis, pleural adhesions, thin-walled cysts in the lower parts of the lungs are visible on X-ray.

How to confirm the presence of worms in the body?

We have come to the most frequently asked questions when visiting a doctor.How to determine if there are worms in the human body?Is it possible to do it yourself without leaving home?

Thus, it is possible to determine the presence of helminthic infection at home only in the following cases:

1. Visualization of worms in feces (adult live or dead helminths, their fragments).Of course, only helminths living in human intestines can be found in feces.As a rule, helminths are detected during mass infestation.
2. Visualization of tapeworm segments in feces.

In all other cases, the diagnosis can be confirmed using 2 basic laboratory diagnostic methods:

1. Various modifications of ovoscopy.Worm eggs have morphological differences and microscopic dimensions;trying to test them with feces is useless.
2. Serological reactions, including PCR.

The range of laboratory tests for different invasions is different.It should be understood that standard stool analysis for helminth eggs and scraping for enterobiosis are the most common examination methods aimed at identifying intestinal helminth infections in risk groups.At the same time, a single microscope is only about 50% informative.In the picture below, you can see what worm eggs look like under a microscope.The vertical scale represents the size in µm.

Drug treatment and chemoprophylaxis

Treatment of human helminthiasis involves the appointment of appropriate anthelmintic, as well as symptomatic and pathogenetic agents.In this article, we will not go into detail about dosages and treatment regimens for individual helminthic infestations;we will only note that the prescription of drugs should be carried out by a doctor (pediatrician, therapist, infectious disease specialist, parasitologist) according to the clinical picture, laboratory examination data and the patient's condition.

Chemical prevention of helminthiasis is the preventive application of anthelmintic drugs active against geohelminthic infections in risk groups and endemic areas.Since the general frequency of geohelminthosis in the population as a whole is low, chemoprophylaxis can be carried out once a year, preferably in autumn or spring. 

Preventive measures

Measures to prevent infection with worms are conventionally divided into individual and public.Individual prevention includes:

1. Observing personal hygiene rules among family members and in groups, teaching children the rules and monitoring their implementation.
2. Thorough processing of greens, vegetables and fruits before direct consumption.
3. Refusal of raw, poorly cooked meat from pigs, cattle and other animals, salted, dried and smoked meat that has not passed sanitary-epidemiological control.
4. Rejection of consumption of fish that has not passed sanitary-epidemiological control, including salted, smoked, dried, caviar and other fish products.
5. Drink only high-quality water for drinking and cooking, including when traveling.
6. Before going to tropical and subtropical countries, it is necessary to consult an infectious disease specialist (parasitologist) and after returning, get recommendations for laboratory diagnostics.An infectious disease specialist also decides on the need for chemical prophylaxis.
7. Refusal to swim in fresh water, walk barefoot or sleep on grass in endemic tropical countries.
8. Refusal to eat on the street, in unverified cafes and other public catering facilities.
9. Annual clinical examination with scrapings for OAC, OAM, standard coproovoscopy and enterobiosis.These measures are especially useful in families with children, adults working in organized children's groups, hospitals, sanatoriums, etc.

Public prevention consists of organizing control of food products sold in stores and markets, timely detection and treatment of sick pets and people infected with the disease.Monitoring of water resources, beautification of populated areas, evaluation of the degree of infection of wild mammals, control of the borders of natural foci of helminthiasis, and the number of stray animals are of great importance.