Correspondence Address:
Prof. Raj Kumar
Department of Pulmonary Medicine, National Centre of Respiratory Allergy, Asthma and Immunology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi - 10 007
India

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Allergy is an immediate Type I hypersensitivity reaction to an allergen. It may affect different organs of the body, particularly the respiratory system. Allergic diseases are a major health concern worldwide. Common respiratory allergic diseases are asthma and allergic rhinitis (AR). Overall, about 300 million people have been found to be suffering from asthma and about 200–250 million people suffer from food allergies. One tenth of the population suffers from drug allergies. Estimated prevalence of rhinitis in the general population is 10%–30% worldwide and 20%–30% of the Indian population. In 1964, a study carried in Delhi reported around 10% of the people are suffering from AR and 1% from asthma.[1] Recently, Indian study on epidemiology of asthma, respiratory symptoms, and chronic bronchitis has also been conducted and covered 12 centers comprising of both rural and urban areas of different parts of India. The prevalence of bronchial asthma for all the 12 centers was reported 2.05% (range, 0.4%–4.8%).[2] Kumar et al. reported asthma prevalence as 8.8% in school girls between the age 4 and 17 years.[3] In another study, pointing socio-economic status of family, the prevalence of asthma in children was found to be 9.4% in lower class, 7.3% in middle class, 9.4% in upper class in urban area of Delhi and 3.9% in the village area of Delhi.[4] Although, recent study showed, asthma and rhinitis often co-exist in the same patient, in children as well as in adults. Asthma is found in up to 38% of patients with AR and nasal symptoms are present in 6%–85% patients with asthma.[5] A wide inter-regional variation in prevalence of asthma has also been observed. The prevalence of allergic airway disease including asthma and AR is on the rise, and air pollution, global warming, and climate change are the main contributing factors.

Aeroallergens play a significant role in the pathogenesis of asthma and rhinitis. Ambient aeroallergens are associated with emergency department visits, hospital admission, and death caused by asthma.[6],[7],[8] The common aeroallergens causing respiratory allergy are pollen grains, fungal spores, house dust mites, animal, and insect allergens. The clinical suspicion of allergic sensitization can be confirmed by demonstrating the presence of allergen specific IgE antibodies in-vivo (skin tests) or in-vitro methods.[9] Although there were many attempts to identify and characterise the clinically relevant pollen in India, the process has not been completed and the information that is available is not up to-date in most places in India. This is mainly because of the vast diversity in terms of flora and fauna, culture and traditions, and the need for expensive equipment for pollen identification and characterization, as well as lack of availability of expert aerobiologists who can accurately identify the pollens and fungi. Pollen causing allergies are quite different in various ecozones which makes it vital to identify pollinosis causing species from all regions and prepare extracts from them for diagnosis and immunotherapy for the benefit of allergic individuals.[10] Therefore, the evidence-based Indian guidelines for the diagnosis of allergic respiratory diseases were prepared by the Vallabhbhai Patel Chest Institute (VPCI) and duly endorsed by the Indian College of Allergy, Asthma and Applied Immunology; South Asia Association of Allergy, Asthma and Clinical Immunology; and National Center of Respiratory Allergy, Asthma and Immunology (NCRAAI). The guideline was framed in a scientific manner to guide and help clinicians for better diagnosis and management of respiratory allergic diseases. The guideline has tried to come out of the different pollen prevalent in different parts of the country.[11]

To control, it is essential to monitor pollen counts so that people can limit the exposure on days the counts are high. Establishing pollen monitoring stations will enable people with allergies to be better prepared and warned about pollen concentrations in different weather conditions and adopt allergen avoidance measures. It will also help to create awareness about pollen concentration in the air, which is one of the major reasons for repeated attacks in asthma patients. Developing a health forecasting system for acute allergic diseases and climate variables will help in providing knowledge for the allergic population.

Pollen levels coupled with seasonal meteorological changes are found to be a better correlate for predicting allergy. The rise in respiratory allergy parallels the rise in indoor and outdoor air pollution. Gases such as SO2 and NO2 affect pollen, and these gases can modify the morphology of the antigen-carrying agents and alter their allergenic potential.[12] A combination of three critical information, pollens and fungi, meteorological changes and air pollution in real time is likely to be the cornerstone of personalised allergy management in the future.

Worldwide the pollen sampling is done by the gold standard volumetric Hirst type sampler, and the gold standard currently is the Burkard sampler.[13] The device involves fully manual operation from the collection to classification of pollen. Since allergen avoidance remains the cornerstone in the management of allergy and asthma. Reliable, accurate, real-time details on the occurrence and abundance of airborne pollen are needed to practice allergen avoidance. Hence, an artificial intelligence and machine learning powered solution to this problem wherein pollen will be automatically identified, classified and the pollen burden in the atmosphere broadcasted to the public on a real time basis.[14]

Once this is established, then these systems can be deployed across the country to update the database of pollen in the various parts of the country. This is very essential because clinically relevant pollen in the north region may not be relevant in southern, as the case may be different in the eastern and western terminus of the country. It is also important to do clinical studies in the community to identify the most clinically relevant allergenic pollen from all the regions of India.

The pollen monitoring stations promote the common proverb prevention is better than cure and will have various long-term implications in the form of improving access to local pollen data and benefit those with allergies. VPCI, Delhi conducted several atmospheric surveys/studies on airborne pollen from time to time for qualitative and quantitative variations over the last three decades in Delhi. Recently, Kumar et al. in 2015, 2017, 2018, reported prevalence in asthma and rhinitis,[15] atmospheric pollen count[16] and Identification of airborne pollen in Delhi[17] and also correlated pollen with a patient's hospital visit.[7] Shivpuri in 1962, 1971, Nair in 1963, Singh et al. in 2003, 1981, 1982 have surveyed airborne in various parts of India.[18],[19],[20],[21]

Vallabhbhai Patel Chest Institute, a renowned medical institute devoted to research, teaching and patient care in the field of chest diseases since its inception. The Institute fulfils the national need for providing relief to a large number of patients in the community suffering from chest diseases. To work in the area of allergy and immunotherapy, this was need to establish the NCRAAI at V. P. Chest Institute, Delhi in 2011. The Centre is fully equipped with latest technology in the field of research, allergy testing for proper diagnosis and efficient management of respiratory allergic diseases through different modalities including immunotherapy. In 2013, the center established pollen count station at the roof of the VPCI and started pollen count collection regularly on a daily basis by using Burkard 1-day and 7-day air samplers. The collected pollen counts are displayed digitally for the public, who are predisposed to allergy caused by pollen and can take precautions. In this area till now, 46th workshops on "Respiratory Allergy: Diagnosis and Management" have been conducted and many physicians have been trained. The Government of India is promoting various activities to increase awareness, impart education and update knowledge about allergic diseases. National level programme with the aim to train doctors in diagnosis and management of allergic disease is being conducted at V. P. Chest Institute, Delhi at frequent intervals.

Furthermore, establishing pollen count station at different parts of the county, we will be able to know the common pollens in different parts of country, update the database of pollen registry, prepare pollen calendars for region specific, measure the levels of pollens which trigger allergy symptoms and require hospitalization and improving access to quality allergen extracts for immunodiagnostics[22] and development for safe delivery of allergen specific immunotherapies.

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