The rise in prevalence of allergic diseases has continued in the industrialized world for more than 50 years and Worldwide, sensitization rates to one or more common allergens among school children are currently approaching 40%-50%
With the changes in the weather conditions, the hypersensitive disorder of the immune system of the body appears to reach its peak.
Allergic diseases including asthma are common conditions and develop as a result of complex interactions between environmental, genetic and epigenetic factors. Approximately 20-30% of the population suffers from at least one of these allergic diseases in India. Prevalence rate of Asthma in children in India has also been studied & the mean prevalence has been found to be 7.2 +/- 5.4%. Childhood asthma among children 13 to 14 years of age has been lower than that in younger children of 6-7 years of age.
“When we see along with socio-economic status, the prevalence was 27.1% in lower class, 33.3% in middle class, 28.6% in upper class in urban area and 11.1% in village area in Delhi. In an Indian study from Bihar in 1972, 38% of Dermatology OPD cases were Atopic Dermatitis in infants. Cow’s Milk Protein Allergy prevalence is 2-7.5%. Dr Waqar Sheikh reported prevalence as 16.48% for food allergies and 15-25% for Ocular allergies in the Indian population”, said Dr. Swati, Fortis Hospital, Mohali during a talk at Millennium School, Mohali.
Although almost any tissue in the body may be affected by allergy, yet it has a predilection for respiratory tissue and skin. The commonest manifestations are Asthma, Allergic Rhinitis, Allergic Conjunctivitis, Drug allergy, Food allergy, Insect allergy, Eczema, Urticaria, Angioedema and Anaphylaxis.
Speaking about the major sources of allergic symptoms Dr. Swati said, “Airborne dust and its particles, which include pollen grains, fungal spores, animal dander, mites and other allergens in indoor air, are major sources of allergic symptoms. They enter into the respiratory tract of human beings and trigger hypersensitivity reaction which is manifested in the form of allergic rhinitis, bronchial asthma, atopic dermatitis, eczema, gastrointestinal and autoimmune diseases.”
“Pollen grains are amongst the earliest known allergens and are found to be the major causes of bronchial asthma and allergic rhinitis. Seasonal allergic rhinitis usually caused by pollen grains of those plants which flower in a particular season for a short duration. Pollens can also irritate the eyes causing Allergic conjunctivitis”, she further added.
There are several reports from Europe and USA that climate change (global warming) increases the duration and concentration of pollens in the air because of early flowering and late finish during the season. Increased cabondioxide enhances the growth of plants and productivity of pollens. The sufferers of seasonal allergy know that some days will be worse than the others depending upon the prevailing weather conditions.
“People usually complain of catching cold soon in every season. That may be because he or she may be suffering from nasal allergy due to pollen grains which is perennial and may last for weeks or months. Whereas, cold usually lasts for 7-10 days”, stated Dr. Swati.
If one parent is atopic, then the chances of the child getting atopy are 50%. If both the parents are atopic then the chances of the child getting affected are 75%. Small houses, inadequate ventilation, dusty environment, usage of carpets and upholstery are recorded to know that dust mites may be the probable allergen. Wet environment and water seepage favors the growth of molds. Day care centers can be the source of recurrent viral and bacterial infections in children.
Speaking about the dire need for an evaluation of suspected allergy Dr. Swati said, “It must include a detailed history, thorough physical examination and appropriate diagnostic tests which include blood tests like complete blood counts, IgE levels, absolute eosinophilic count, allergy skin test, RAST and radiological investigations.”
“With the advent of new standardized tests and tools, the quest for allergy has found new horizons and success in finding out the allergen and curing the patient completely. But unlike other diseases, allergist needs to be thorough with the patient’s past and present history, family history as well as his diet, lifestyle, outdoor and indoor environments, drugs and so on”, she further added.
Irrespective of the type of allergic symptoms, allergies are chronic diseases seriously affecting the quality of life and may even sometimes be fatal. Sufferer has disruptive impact on the life affecting performance at office, home or school. Therefore, fighting with them may demand change of lifestyle, or even profession, maintaining allergy avoidance, long term pharmacotherapy and even immunotherapy which gives very promising results.