Parasites and allergies – interrelationship and mechanisms of influence on the human body

Allergies are one of the most common diseases of our time and are considered an epidemic in developed countries. Millions of people around the world experience allergic reactions to everything from dust and pollen to certain foods. However, few are aware that intestinal parasites may be behind these allergies.

The global impact of allergies

Allergies affect an increasing number of people worldwide. Approximately 4 million people suffer from allergies and their prevalence has increased significantly in recent decades, especially in developed countries. This alarming increase has led to the phenomenon being called an “allergy epidemic”.

Studies by the World Health Organization (WHO) have shown that up to 80% of diseases in modern humans can be caused by various forms of helminths or are a consequence of parasitism. According to parasitologists, allergies are often the first and main sign of helminth (worm) infestation in internal organs and tissues, including the skin. Helminths can be found not only in the intestines, but also in vital organs: liver, heart, lungs, bronchi, throat, skin, and brain.

Conventional causes of allergies

Conventional causes of allergies

Although the mechanisms of allergies are complex, the main known cause is exposure to allergens, substances that trigger an exaggerated immune response. Allergens can range from pollen and dust to specific foods, dust mites and even pets. Repeated exposure to these allergens sensitizes the immune system, which produces specific IgE antibodies to fight the ‘invader’. On re-exposure, these antibodies bind to mast cells, immune cells that release histamines and other inflammatory chemicals, causing allergic symptoms.

A hidden cause: intestinal parasites

In addition to classic allergens, an often overlooked factor plays a major role in triggering and exacerbating allergies: intestinal parasite infections. Studies have shown that both adult helminths and their larvae can cause allergic reactions. These tiny invaders, invisible to the naked eye, can significantly disrupt the immune system and contribute to allergies through several mechanisms:

• Release of toxins and metabolites. Intestinal parasites produce toxins and metabolites (chemicals) that can overstimulate the immune system, causing a state of chronic low-grade inflammation. This inflammation can sensitize the body to allergens, increasing allergic reactions;
• Imbalance of intestinal flora. Parasites can disrupt the balance of the intestinal flora, destroying beneficial bacteria and favoring the proliferation of pathogenic bacteria. Intestinal flora plays a crucial role in modulating the immune system, and the imbalance created by parasites can increase allergic reactions;
• Impairment of the intestinal barrier. Parasites can damage the intestinal barrier, allowing food allergens to enter the body more easily. This increased permeability of the gut can increase allergic reactions to certain foods;
• Tissue damage. Helminth larvae can enter the bloodstream or lymphatic vessels and migrate from one organ to another, causing toxic stress and tissue damage. These parasites feed and release the toxic products of their metabolism directly into the internal environment, substances that spread through the bloodstream throughout the body. They can poison the central nervous system and cause hormonal deficiencies or imbalances. Even helminth eggs attached to the intestinal wall can cause inflammation and swelling, the first signs of an allergic reaction.
• Increased sensitivity to allergens. Toxic substances (products of helminth metabolism and decomposition), as foreign bodies to the body, increase sensitivity to various allergens – food, pollen, mites, animal hair, down, medicines, etc.

Manifestations of allergic reactions to parasitic infections

Symptoms of helminth-mediated allergic reactions may vary depending on the type of helminth, the site of infection, and the individual susceptibility of the host. Common symptoms may include:

1.Increased sensitivity to allergens. Patients with parasitic infections may have an increased sensitivity to various allergens, such as pollen, dust, certain foods, and other substances, which can lead to an exacerbation of allergic symptoms.

2.Skin rashes and itching. The appearance of rashes accompanied by severe itching may be the result of an allergic reaction to the presence of parasites in the body.

3.Respiratory problems. Some parasites can cause inflammation of the respiratory tract, resulting in symptoms such as coughing, dyspnea, wheezing, and other manifestations of an allergic reaction.

4.Edema and rashes. Swelling of the face, lips, throat, or other parts of the body combined with the appearance of a rash, dermatitis, or eczema may indicate an allergic reaction secondary to a parasitic infection.

5.Gastrointestinal disorders. Some parasites can cause digestive problems such as diarrhea, constipation, and other gastrointestinal symptoms that can worsen the body’s allergic response.

6.Neurological disorders. Fatigue, headaches, and sleep disturbances may be present with parasitic infections, adversely affecting overall health and exacerbating allergic reactions.

7.Other symptoms. Fever, weight loss, and iron deficiency may occur as a result of parasitic infections, affecting the body’s ability to cope with allergens and exacerbating allergic symptoms.

Micronutrient deficiencies and allergies

The development of allergic reactions is favored by parasite-induced suppression of enzyme activity in the gastrointestinal tract. Enzymes function and are produced by the body with the help of trace elements – zinc, silicon, chromium, selenium, manganese and copper. Parasites also require these micronutrients for growth, development and reproduction. As long as a person is able to replace the nutrient losses caused by parasite growth, they remain healthy. However, once the body is weakened (e.g., by stress), micronutrient deficiencies hinder its ability to respond effectively to parasitic, viral, bacterial, etc. attacks.

It is hypothesized that immediate-type allergic reactions evolved during phylogenetic development as defense reactions against parasites, involving effector cells such as eosinophils, mast cells, basophils, B lymphocytes and IgE antibodies. In the absence of adequate exposure to antigens, atopy does not provide protection but leads to the development of allergic disease.

The authors believe that the main reason for the increased prevalence of allergic diseases, including bronchial asthma, is the improved epidemiological situation. According to the theory of infectious diseases, the bacterial and viral spectrum in the environment has changed in the last 30-40 years due to the widespread use of antibiotics and the success in combating infectious diseases such as tuberculosis, malaria, etc., as well as improved sanitary and hygienic living conditions.

Interaction of allergic and parasitic diseases

Despite the fact that many of the mechanisms of immune regulation in helminthic diseases have been studied, the question of the reciprocal influence of allergic and parasitic diseases remains controversial. Based on epidemiologic, experimental and clinical studies, there are mutually exclusive views:

1.Atopic predisposition prevents helminth infections. The theory suggests that people with atopic predisposition (predisposition to allergies) have a Th2-oriented immune system that protects them from helminth infections. Th2 cytokines can induce mastocytosis, eosinophilia, IgE synthesis, and prevent infection with some intestinal helminths.

2.Helminthiases prevent/reduce the development of atopic diseases. Evidence for the second theory comes from experimental and epidemiological data showing a reduction in bronchoconstriction symptoms after schistosomiasis infection. The theory suggests that the influence of parasitic pathogens reduces the development of atopic diseases by modulating the immune system.

3.Helminthiases favor the development of atopic diseases or increase their manifestations. A contrary theory suggests that helminth infections may favor the development of atopic diseases or increase their manifestations.

Confirmation of these theories could lead to the discovery of new ways to treat allergies or the identification of new causative allergens or allergy triggers.

It is important to note that the interaction between parasitic infections and allergies requires further research to fully understand the mechanisms of this process. A thorough understanding of this relationship could contribute to the development of new therapeutic strategies for the treatment of allergic diseases.

Allergies are no longer just a problem of exposure to conventional allergens.Intestinal parasite infections play a significant role in triggering and exacerbating allergies and are an often overlooked cause.A holistic approach that combines allergen avoidance with identification and treatment of parasite infections can provide an effective solution to combat allergies and improve overall health.