New allergenic pollens of Delhi State, India, and their clinical significance.

Antigenic extracts of 26 new pollen types were assessed on 175 patients with respiratory allergy for their allergenicity, using the intradermal test. A total of 4,550 intradermal tests were performed in addition to 1,040 skin tests performed on 40 non-allergic healthy individuals as a control. Fisher's Extract Probability Test was used to determine the statistical significance of the allergenicity, expressed in percentages of markedly positive skin reactions (2+ and above). Only 13 of the 26 pollen types investigated proved to be statistically significant as possessing allergenicity. The relative sensitivity of different diagnostic tests was also assessed. Markedly positive reactions evaluated by Passive Transfer (P-K), conjunctival and bronchial challenge tests were found to be equally significant. The P-K and bronchial challenge tests gave significant correlation with markedly positive intradermal tests.