Neonatal birch‐pollen contact and subsequent allergy to birch pollen

Abstract

Summary It is shown by regression analysis that the risk of immediate hypersensitivity to birch pollen, as measured by a skin test, is positively correlated with the quantity of birch male flowers and the number of non‐rainy days in the first birch flowering season (May) met in infancy. The risk is also dependent on the month of birth, with maximal risk associated with birth in Februarys–April. The results suggest that early pollen contacts, particularly during the first 6 months of life, increase the risk of pollen allergy for a period of 20 years. We estimate that elimination of early birch pollen contacts could have reduced the prevalence of immediate hypersensitivity to birch by 28% in our age group 0–19 years.

The control of allergens of dust mites and domestic pets: a position paper

“…Early infancy has been identified as the critical period for primary sensitization to occur [4], and children born just before the birch pollen season in Scandinavia have a higher risk of sensitization to birch pollen than those born after the season [5]. Similar observations have been made in relation to house-dust mite exposure received by children born in the autumn when mite numbers tend to be higher than at other times of the year [6,7], and cat and dog allergen exposure in infancy [8,9].…”

Allergic Rhinitis and its Impact on Asthma (ARIA) 2008*

“…The month of birth has been related to allergic rhinitis but findings could have been biased because negative studies have not been published (267)(268)(269)(270)(271).…”

Cord blood cytokines and chemokines and development of allergic disease

“…Exposure to allergens early in life may have an impact on the incidence of allergy many years later (1)(2)(3). The initial exposures to ubiquitous allergens invariably occur during the first year of life, or even before birth (4).…”