Farm residence and exposures and the risk of allergic diseases in New Zealand children

Abstract

Despite finding a protective effect of early-life animal exposures, we found a greater prevalence of allergic disease on farms.

Asthma and atopy – the price of affluence?

“…The discrepant results in this study were partly explained by small, if any, differences e.g. in animal contacts, socioeconomic status and in the use of coal and wood fuels between farm and nonfarm residents in New Zealand (122).…”

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

“…The children of farmers have less allergic rhinitis than other children, suggesting that a countryside lifestyle could possibly protect children from the development of allergy (855,(965)(966)(967)(968)(969). Most consistently, the ÔprotectiveÕ farm effect was related to livestock farming and thus to microbial exposure (753).…”

Protective effects of farming on allergies and asthma: have we learnt anything since 1873?

“…Consumption of unpasteurized farm milk in farmers' and nonfarmers' children has also been shown to be protective in several of the farmers' studies [10,14,17,56,57]. The etiological mechanisms are unclear, but probiotic bacteria or other currently unidentified non-microbial components in farm milk may play a role.…”

“…A related issue is that a number of studies have found consistently low prevalences of allergies and asthma in farmers' children, both in high-income countries such as Canada, the USA, Australia, New Zealand and Europe [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], and in lowincome countries including Mongolia and Southern Africa [21,22]. These protective effects for allergies and asthma have also been observed in adult farmers [23][24][25][26][27][28][29][30][31][32][33][34][35][36], despite the increased risks of other respiratory conditions, such as chronic obstructive pulmonary disease, reduced lung function and farmers' lung [37].…”