Aeroallergens in clinical practice of allergy in India- ARIA Asia Pacific Workshop report.

Allergic diseases such as bronchial asthma, allergic rhinitis and atopic dermatitis are dramatically increasing all over the world including developing countries like India. Today, more than 30% of the population is known to suffer from one or other allergic ailment. Major causative agents implicated are pollen grains, fungal spores, dust mites, insect debris, animal epithelia, etc. Several aerobiological studies have been conducted in different parts of the country to ascertain aerial concentration and seasonality of pollen grains and fungi. Recently, an "All India Coordinated Project on Aeroallergens and Human Health" was undertaken by us to discover the quantitative and qualitative prevalence of aerosols at 18 different centers in the country. Allergenically important airborne pollen identified by clinico-immunologic evaluation are Alnus, Amaranthus, Argemone, Brassica, Cannabis, Cassia, Cedrus, Chenopodium, Cocos, Holoptelia, Mallotus, Morus, Parthenium, Prosopis juliflora, Quercus, Ricinus communis, and grasses such as Cenchrus, Cynodon, Imperata, Pennisetum etc. Cross-reactivity of the IgE antibodies is a common phenomenon among various pollen allergens. Ricinus communis pollen a commonly growing weed/shrub in India, cross-reacts with latex (Hevea brasiliensis), Mercurialis annua and also with seeds of Ricinus communis--all belonging to family Euphorbiaceae but geographically distantly located. Areca catechu cross-reacts with other members of Arecaceae such as Phoenix sylvestris, Cocos nucifera and Borassus flabelifer while pollen of Holoptelia integrifolia from India cross reacts with pollen of Parietaria judaica from Mediterranean Europe, both of which are members of family Urticaceae. Several reports on pollen and fruit syndrome have been analyzed. Experiments conducted by us revealed that pollutants (NO2 and SO2) not only affect pollen morphology but also changes its allergenic potency.