Who is the dust mite and how do its by‑products affect humans? - briefly
Dust mites are microscopic arachnids inhabiting household textiles and feeding on human skin debris. Their fecal particles and body fragments act as potent allergens that provoke respiratory inflammation and skin irritation in sensitive people.
Who is the dust mite and how do its by‑products affect humans? - in detail
Dust mites are microscopic arachnids belonging to the family Pyroglyphidae. Adult individuals measure 0.2–0.3 mm, possess eight legs, and thrive in warm, humid environments such as bedding, upholstered furniture, and carpet fibers. They feed on shed human skin cells, reproducing rapidly when relative humidity exceeds 50 % and temperature remains between 20 °C and 25 °C. A female can lay up to 100 eggs in her lifetime, completing a life cycle in 2–3 weeks under optimal conditions.
The primary substances released by these organisms include:
- Fecal pellets containing digested skin proteins, notably Der p 1 and Der f 1 enzymes.
- Body fragments shed during molting.
- Allergenic proteins present in saliva and secretions.
When inhaled or contacted, these particles trigger immune responses in susceptible individuals. The mechanisms involve:
- IgE-mediated sensitization – specific antibodies recognize mite allergens, leading to mast cell activation and release of histamine, prostaglandins, and leukotrienes.
- Inflammatory cascade – cytokines such as IL‑4, IL‑5, and IL‑13 promote eosinophil recruitment and airway hyper‑responsiveness.
- Skin irritation – direct contact with allergen‑laden debris can exacerbate atopic dermatitis and provoke urticaria.
Clinical manifestations range from intermittent sneezing and nasal congestion to chronic asthma, characterized by wheezing, bronchial obstruction, and reduced lung function. Dermatological effects include intensified itching, erythema, and secondary infections due to scratching. In occupational settings, prolonged exposure may aggravate allergic rhinitis and contribute to decreased productivity.
Control strategies focus on reducing environmental loads:
- Maintain indoor humidity below 45 % using dehumidifiers.
- Wash bedding weekly in water hotter than 60 °C.
- Employ allergen‑impermeable mattress and pillow encasements.
- Vacuum with HEPA‑filtered equipment regularly.
- Replace carpet with hard flooring where feasible.
Implementing these measures lowers mite populations, diminishes allergen concentrations, and mitigates the health impact on exposed individuals.