[Sensitization and occupational asthma in poultry workers]

A high prevalence of asthma has been reported in poultry farmers. Our aim was to determine air contaminants in poultry confinement buildings and the prevalence of occupational asthma in these workers.

Spanish poultry farmers who participated in the European Study Prevalence and Risk Factors for Airway Obstruction in Farmers, who worked inside confinement buildings, were enrolled in a cross-sectional study that included the measurement of air contaminants (ammonia, total dust, endotoxin and microorganisms), symptoms, skin testing with common and poultry-related allergens, and a specific bronchial challenge. The Spearman correlation coefficient was used to assess the correlation between air contaminants.

14/15 poultry farmers participated in the study (response index: 93.3%). Concentrations of air contaminants in the confinement buildings [median (interquartile range)] were: 7.5 (5-20) ppm for ammonia, 2.6 (1.8-4.6) mg/m3 for total dust, 137.1 (58.6-243.9) ng/m3 for endotoxin and 7,600 (907-27,750) colony-forming units/m3 * 103 for bacteria. Endotoxin correlated with bacterial concentration (r = 0.69, p < 0.01). 5/14 poultry farmers reported wheezing and/or asthma within the last year (35.7%), and in 2 of them spirometry demonstrated current asthma (14.3%). Specific bronchial provocation confirmed the diagnosis of occupational asthma in one subject with current asthma sensitized to the storage mite Lepidoglyphos destructor (7.1%).

One third of poultry farmers working inside confinement buildings reported wheezing, that is partly attributable to occupational asthma caused by storage mites.