Symptoms, diagnosis, and treatment of the most common human helminthiasis

In this article we will try to find out the most common symptoms of helminthiasis in adults, whether it can be asymptomatic, and the most common types of helminth infections in our country.

Introduction to terminology

Human helminth infections are usually caused by three classes of parasitic helminths: Nematoda (nematodes) - roundworms, Cestodea (tapeworms) - tapeworms, Trematodes (trematodes) - flukes.Based on the class of pathogen, all human helminthiasis are generally divided into:

1. Nematodes are helminth infections related to infection with roundworms or their larvae.The best-known nematode diseases are pinwormiasis, ascariasis, hookworm disease, toxocariasis, and strongyloidiasis.
2. Taeniasis is caused by parasitic tapeworms or their larvae.The most common taeniasis are dilofilariasis, taeniasis and taeniasis, hymenoderma and hydatid disease.
3. Flukes are helminth infections caused by different types of flukes.The most common diseases in my country are opiates and clonorchiasis, less common is fascioliasis, and extremely rare is paragonimiasis.

As far as our territory is concerned, all helminth diseases can be divided into:

1. Typical, that is, often found in our population;
2. Exoticism, caused by population migration and travel to other countries.

Detection and treatment of exotic helminth infections is a more complex and time-consuming process because laboratories may not have the reagents needed to perform laboratory tests.The following types of worm infections are typical on our territory.

Which groups are most vulnerable to infection?

Worm infections are more common in people who:

1. Young children have an active understanding of the world and lack personal hygiene skills.
2. Grouping of children (kindergarten, school, camp, nursing home, etc.).Close interactions, shared habitats and exchange of toys contribute to the spread of soil worms, whose life cycle is simple.
3. Adults who have close contact with and work with children, including teachers and parents.
4. People with certain dietary habits: eating raw or unprocessed meat, fish, seafood, herbs, etc.Great emphasis on ethnic cuisine (sushi, stroganina, yukola, porsa and other dishes), a fondness for drying, pickling and smoking.
5. People living in endemic areas, the tropics and subtropics.
6. People who live in poor sanitary conditions and lack access to high-quality water and sanitation facilities.
7. A person closely associated with agriculture and cattle raising, and with animal life.

When and who needs to be tested?

According to the risk groups and the characteristics of the course of helminth infection, helminth disease examination must be carried out in the following situations:

1. Children, both organized and disorganized, develop symptoms at least once a year without any symptoms.
2. Adults who work with children and in catering establishments, doctors, sellers of children's products and food.
3. Children and adults attend educational institutions, nursing homes, hospitals, boarding houses, hospices and other institutions that house large numbers of people in an area.
4. Children and adults with cutaneous and bronchopulmonary allergic diseases that are resistant to conventional treatments and elimination diets.
5. Children and adults with symptoms of chronic damage to the gastrointestinal tract: nausea, vomiting, diffuse abdominal pain, diarrhea, pain in the epigastric and periumbilical region, malabsorption syndromes.
6. Children and adults with symptoms of damage to the hepatobiliary system - hepatosplenomegaly, jaundice, right rib pain, AST, ALT, GGTP, elevated alkaline phosphatase, portal hypertension.
7. Prolonged, unexplained, low-grade fever in children and adults.
8. Children and adults with severe frailty syndrome: Frequent headaches, weight loss, bulimia or loss of appetite, unexplained weakness, fatigue, sleep disturbances.
9. Children and adults with microcytic and normocytic anemia are resistant to conventional treatments.Vitamin B12 deficiency anemia is associated with 2-4% of cases of dilofilariasis and, less commonly, taeniasis, ascariasis, and other helminthiasis.

Characteristics of the worm infection process

The process of any worm infection can be divided into several stages:

1. Infection and its clinical manifestations.Most helminth infections have no symptoms, but strongyloidiasis, hookworm, and some other helminthiasis present with something called cercariasis, a disease caused by larvae that invade the skin.
2. The incubation period is the time from the moment of infection to the first clinical manifestations.
3. The acute phase is most often caused by the migration of larvae in the human body, molting, maturation into sexually mature individuals, first egg laying, and the first encounter of the body with unfamiliar antigens.The acute phase usually lasts from a few days to a few weeks.Sometimes the acute phase is absent or less expressed, this is more common in low-grade attacks or in Aboriginal people with "immune memory".
4. The chronic phase occurs in the absence or ineffectiveness of treatment and is associated with direct effects in sexually mature individuals.

The duration of infection depends on the lifespan of the worm and the likelihood of self-infection.

From this point of view, the course of all helminthiasis can be represented in the form of several basic schemes.

1. Option 1: The course of the disease is sinusoidal.Onset (moment of infection) - symptoms increase to a certain level (severity) - transition to the chronic phase, with periodic worsening.This type of course is characteristic of opiodriasis, clonorchiasis, fascioliasis, and strongyloidiasis.
2. Option 2: The course of helminthiasis takes the form of a plateau.After infection, symptoms increase to a certain level, after which the patient notices that the symptoms remain the same or decrease and disappear.Many invasions follow a similar process: trichinellosis, taeniasis, diye filariasis, ascariasis.
3. Option 3: The course of helminthiasis is characterized by worsening symptoms, which can eventually lead to death.These are usually large-scale invasions or helminthiasis that occur with transmission in the context of immunodeficiency (disseminated strongyloidiasis).

Next, let’s look at where worms live in the human body.Helminth infection can affect any human organ, however, for the sake of systematization, several main "favorite" localizations within the host can be identified:

1. The intestines are the most logical habitat for many human worms, such as roundworms, pinworms, whipworms, hookworms, and cattle and pork tapeworms.In one of these ways, the parasite attaches to the intestinal wall and carries out its "subversive" activities, most commonly by stealing nutrients from the host's food.
2. The liver and bile ducts are favorite habitats of Opisthorchis, Clonorchis, and Fasciolopsis.In addition, the liver is often affected during the migration of worm larvae such as paragonimiasis and Echinococcus tapeworms.
3. Lungs and bronchi.The life cycle of many nematodes (roundworms, hookworms, intestinal eels) cannot proceed without larvae migrating through the bronchopulmonary system.As with other worms, the lungs are the ultimate target and habitat for adult individuals (paragonimiasis).
4. central nervous system.It is most commonly affected by cysticercosis, hydatid disease, toxocariasis, paragonimiasis and other invasions.This is usually due to migration of the larval form and its spread through the bloodstream.
5. Often, the skin becomes a habitat for larvae as well as various filarial worms.
6. Eyes - Filariasis, toxocariasis.
7. The venous plexus of the bladder, uterus, and intestines in patients with schistosomiasis.

Symptoms of helminthiasis

In general, clinical manifestations of helminth infection include the following syndromes:

1. Toxic allergies.The main causes of allergic and toxic reactions are the metabolites of adult and larval insects and the toxins they release.Worms in humans can cause skin rashes such as hives, allergic and atopic dermatitis, and sometimes eczema.The rash is relapsing and traditional treatments are ineffective.
2. indigestion.Symptoms of indigestion include nausea, vomiting, heartburn, burping, bitter mouth, and gas.It is common to have diarrhea or loose stools without increasing the frequency of bowel movements.Indigestion is more common with intestinal helminths (ascariasis, whipworm, etc.) and rarely occurs with tissue helminths (hydatid, cysticercosis, toxocariasis, etc.).
3. Dyspepsia and malabsorption syndromes.It is also more common with intestinal invasions, especially those where sexually mature parasites live in the small intestine and duodenum (taeniasis, dilofilariasis, etc.).
4. Abdominal Pain: Children - More common is diffuse abdominal pain, localized in the umbilical area, right iliac area, similar to appendicitis.In adults, the localization of pain is more specific.Sometimes, the pain syndrome caused by a helminth infection may resemble an "acute abdomen."
5. Bronchopulmonary.The most common cause is migration of parasitic larvae into the alveoli and then to the bronchial tree, trachea, and oropharynx.The main symptoms of this stage are cough, usually sputum, accompanied by mucus or mucopurulent sputum, wet and dry wheezing, and the nature of breathing changes to forced or heavy, accompanied by prolonged expiration.With such attacks (ascariasis, strongyloidiasis, hookworm disease), Loeffler's syndrome can be observed.In some invasions, such as paragonimiasis, the lungs are the usual habitat for adults.The clinical manifestations of this case are somewhat different.Chronic cough with bloody sputum, hemoptysis, and radiological changes such as pulmonary fibrosis and cystic lung tissue lesions often resemble tuberculosis.
6. Worms in humans can cause anemia syndromes.Anemia may occur due to direct consumption of the host's blood (hookworms), theft of the host's blood (ascariasis, taeniasis, taeniasis, etc.), gastrointestinal dysfunction (taeniasis, taeniasis, etc.), and exposure to toxins.Anemia is more commonly caused by microcytic iron deficiency and, in some helminthiasis, by macrocytic iron deficiency and B-12 deficiency.
7. Weakness is a sign of the presence of worms in the body and is characterized by sleep disturbances, sleep disturbances, irritability, increased aggression, increased fatigue, hyperactivity and attention deficit in children.Patients have difficulty concentrating on work and concentrating.Infected people may experience unexplained weight loss, loss of appetite (or, conversely, increased appetite).
8. Toxic inflammatory syndrome is manifested by an increase in body temperature to 38 degrees and above, myalgia and arthralgia, leukocytosis, and increased ESR in CBC.Its severity depends on the patient's immune status and the stage of invasion.Fever and flu-like symptoms are more common in the acute phase than in the chronic phase.The chronic phase is characterized by low-grade fever or normothermia.
9. Helminths in humans are often responsible for unexplained asymptomatic eosinophilia.Eosinophilia is the most characteristic feature of nematodes and flukes and may be accompanied by a general leukocytosis.

In the table below we have tried to summarize the available information on the symptoms of helminth infections that accompany the most common helminth infections in humans.

helminthiasis	symptoms of infection	incubation period	acute phase	Chronic phase
pinworm disease	no	10-15 days	Perianal itching, diffuse abdominal pain, and rarely diarrhea, nausea, and vomiting.Sleep disturbances, nighttime screaming, and crying in children.Persistent vulvovaginitis and labial adhesion. The total time of invasion is about one or two months (if there is no reinfection)
Ascariasis	no	about a week	Up to 2 weeks, the acute phase is caused by the migration of larvae.Symptoms during this period include fever, muscle and joint pain, rash and itching, and signs of bronchitis or pneumonia (eosinophilic infiltrative changes in lung tissue).Bronchial obstruction may occur.	Loss of appetite, nausea, vomiting, abdominal pain (near navel, right iliac area), intestinal gurgling, and bloating.Symptoms of weakness are persistent headaches, weakness, and fatigue.Symptoms of anemia and vitamin deficiency.Total duration of invasion (without reinfection) - 1 year
Trouble	no	1-1.5 months	Pain in the large intestine and right iliac area, nausea, vomiting, salivation, flatulence, unsteady stools, blood and mucus in the stool (the total invasion time is 5-7 years).
Diphyllia filariasis	no	As the clinical manifestations of the invasion gradually develop, are erased	There is no such acute phase.Symptoms occur and progress slowly.Generalized weakness, gradually worsening over time, rash, diffuse abdominal pain, sometimes in the right iliac region, nausea, vomiting, loss of appetite and progressive weight loss, unstable stools, signs of anemia, glossitis, hepatosplenomegaly, neurological symptoms (paresthesia, impaired sensitivity and motor function, etc.). Invasions can last up to 10 years or more.
Taeniasis and Taeniasis	no	As the clinical manifestations of the invasion gradually develop, are erased	There is no such acute phase.The following symptoms appear and worsen: weakness, fatigue, headache and other symptoms of weakness, mild or moderate anemia, diffuse abdominal pain and discomfort, overeating or loss of appetite, progressive weight loss, drooling, nausea, vomiting, rashes such as urticaria, and rarely damage to the nervous system, such as Ménière syndrome, epileptiform seizures.
Metatesticular disease	no	2-4 weeks	Increased body temperature, weakness, fatigue, eosinophilia and leukocytosis, abdominal and liver pain, loose stools, allergic rash, hepatosplenomegaly, jaundice.	Symptoms include intestinal and hepatobiliary indigestion, hepatomegaly, jaundice, liver pain, biliary colic, and low back pain (pancreatitis), which may gradually aggravate liver failure.
clonorchiasis	no	2-3 weeks	Same as metatesticular disease, but more pronounced	Same as opioditis.High likelihood of developing cirrhosis and cholangiocarcinoma
Hookworms and nematodes	2-3 days after infection, a papular or urticarial itchy rash appears at the site of larval invasion, often resembling a tortuous tunnel.The duration of this period is up to 1.5-2 weeks.	almost non-existent	Approximately 2-4 weeks due to larval migration.Fever, rash, bronchitis, bronchopneumonia symptoms - cough, wet cough, dry wheezing, sometimes bronchial obstruction.The development of volatile eosinophilic infiltrates in 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 and edema syndrome.Nausea, vomiting, upper abdominal pain, flatulence, fatigue, headache, and general weakness.The total duration of the invasion was 20 years.
membranous dermatosis	no	Implicitly expressed, 2-3 weeks are enough for the maturation from larva to adult	Therefore, the acute phase is not obvious; symptoms worsen and manifest as nausea, vomiting, salivation, diffuse abdominal pain, and loose stools.Damage to the nervous system manifests as headache, dizziness, and fainting.Manifestations of allergies - exanthematous rash, urticaria, Kunkel's edema, allergic rhinitis.The skin is pale with a jaundiced tint.Body temperature is usually normal.
Fascioliasis	no	1-8 weeks	Fever, liver and epigastric pain, jaundice, hepatomegaly, loose stools, allergic rash, eosinophilia, and leukocytosis	Hepatomegaly, liver pain, hepatobiliary dyspepsia, exacerbation of liver failure, secondary cholecystitis and pancreatitis
strongyloidiasis	On days 1-2, slight itching and pimples will appear at the site where the larvae invade, which will disappear soon.	almost non-existent	On the 3rd to 4th day after infection, fever, myalgia, arthralgia, cough with phlegm, wet and dry wheezing, and bronchial obstruction may occur.X-ray shows volatile eosinophilic infiltrate (Leffler syndrome).Allergic rashes often appear on the skin.	Pain in the upper abdomen and around the umbilicus, less commonly in the liver, belching, heartburn, nausea, vomiting, loss of appetite, weight loss, biliary indigestion, diarrhea (usually enteritis type, with few impurities in the feces, usually with a large amount of invasion), hepatomegaly, and jaundice.Infections can persist for years due to regular self-infections.
trichinellosis	Abdominal pain, nausea, vomiting, and diarrhea may occur	1-2 days to 4-5 weeks, average 10-25 days	After infection, first the intestinal phase begins - abdominal pain, nausea, diarrhea, and then all over the body - severe muscle pain, swelling of the eyelids, face, and (less often) the trunk (less often), rash depending on the type Rash, bleeding in severe cases, and high (sometimes low) fever for several weeks.	Larvae are encapsulated and maintained in skeletal muscle for 10 years or more.
paragonimiasis	no	2-3 weeks, can be shortened to a few days	Abdominal pain, acute abdominal pain, diarrhea.Gastrointestinal symptoms are replaced by symptoms of bronchial and pulmonary tissue damage—phlegmous cough, chest pain, pneumonia, effusion pleurisy	Fever or low-grade fever for a long time, long-term cough with bloody sputum, hemoptysis, chest pain, shortness of breath, weight loss, X-ray visible pulmonary fibrosis, pleural adhesions, and thin-walled cysts in the lower part of the lungs

How to confirm that there are parasites in the body?

We discuss the most common questions asked when visiting the doctor.How to tell if there are bugs in a human body?Can you do it yourself without leaving home?

Therefore, it is possible to determine whether a worm infestation is present in your home only if:

1. Visualization of worms in feces (adult live or dead worms, their fragments).Of course, only those worms that live in the human intestine can be found in feces.Typically, worms are discovered during mass infections.
2. Visualization of tapeworm segments in feces.

In all other cases, 2 main laboratory diagnostic methods can be used to confirm the diagnosis:

1. Various modifications of oophoroscopy.Eggs vary in morphology and microscopic size; trying to check for them in stool is useless.
2. Serological reactions, including PCR.

For different intrusions, the scope of laboratory testing is different.It is important to understand that standard stool analysis for worm eggs and scraping for enterobiasis are screening methods designed to identify the most common intestinal helminth infections in at-risk populations.At the same time, a single microscopic examination only provides about 50% of the information.You can see what the eggs look like under a microscope in the picture below.Vertical scale indicates size in microns.

Drug therapy and chemoprevention

Treatment of human helminthiasis includes prescribing appropriate anthelmintic drugs as well as symptomatic and causative drugs.In this article we will not consider in detail the dosage and treatment options for individual helminth infections; we will only note that the drug prescription should be made by a doctor (pediatrician, therapist, infectious disease specialist, parasitologist) based on the clinical situation, laboratory test data and the patient's profile.

Chemoprevention of helminthiasis refers to the preventive administration of anthelmintic drugs effective against terrestrial helminth infections in at-risk populations and endemic areas.Because the overall incidence of geohelminths is low in the entire population, chemical prophylaxis can be administered annually, preferably in the fall or spring. 

Precautions

Measures to prevent helminth infection are generally divided into two categories: personal and public.Personal prevention includes:

1. Observe personal hygiene rules for family members and groups, teach children the rules and monitor their implementation.
2. Process vegetables, greens and fruits thoroughly before eating them directly.
3. Refuse to eat raw, undercooked pig, cow and other animal meat, as well as cured, dried and smoked meat that has not been controlled by hygiene and epidemiology.
4. Refuse to eat fish that has not been subject to sanitary and epidemiological controls, including salted, smoked, dried, caviar and other fish products.
5. Use only high-quality water for drinking and cooking, including when traveling.
6. Before traveling to tropical and subtropical countries, it is necessary to obtain the advice of an infectious disease specialist (parasitologist) as well as advice on laboratory diagnosis upon return.Infectious disease specialists also determine whether chemoprophylaxis is necessary.
7. In popular tropical countries, avoid swimming in fresh water, walking barefoot or lying on the grass.
8. Refuse to eat food on the streets, in unverified cafes and other public dining venues.
9. Annual clinical examination including OAC, OAM, standard fecal enteroscopy and curettage of pinworms was performed.These activities are especially important for families with children, adults working in organized children's groups, hospitals, nursing homes, etc.

Public prevention includes organizing the control of food sold in stores and markets, timely identification and treatment of sick livestock and infected persons.Very important among these are monitoring of water resources, improvement of densely populated areas, assessment of infection levels in wild mammals, control of the extent of natural foci of helminthiasis and the number of stray animals.