title: Farmer's lung disease and microbiological composition of hay: a case-control study.
abstract: Previous studies performed in France have suggested that handling hay contaminated with high amounts of moulds, and especially Absidia corymbifera and Eurotium amstelodami, may favour farmer's lung disease. The circumstances favouring farmer's lung disease and the distinctive microbiological composition of hay samples that provoke attacks need to be specified. We present a case-control study which investigates the agricultural practices and the microbiological composition of hay handled in patients with farmer's lung disease as compared to those of a representative control population. Ten cases identified the hay they were handling at the onset of symptoms. The location, type of farm and working conditions were similar to those of the control farms. Conversely, the microbiological composition of hay differed, with significantly higher amounts of E. amstelodami (P < 0.01), A. corymbifera (P = 0.003), mesophilic Streptomyces (P < 0.01), thermophilic Streptomyces (P < 0.01) and Saccharomonospora viridis (P < 0.01) than in the control population. Our results demonstrate that hay identified by patients as having a harmful effect is characterized by a higher total amount of microorganisms, notably five microorganisms that seem discriminative. Mean concentrations are 2- to 115-fold higher in hay suspected to cause symptoms than in hay from a representative panel of farms. Handling hay with high amounts of these five microorganisms constitutes a risk factor for farmer's lung disease that should be considered for the development of prophylactic measures.
authors.affiliation: Department of Mycology, Laboratory of Parasitology and Mycology, University Hospital J. Minjoz, Boulevard Fleming, 25030 Besancon, France. sandrine.roussel@univ-fcomte.fr
authors.forename: Sandrine
authors.initials: S
authors.lastname: Roussel
authors.forename: Gabriel
authors.initials: G
authors.lastname: Reboux
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Dalphin
authors.forename: Didier
authors.initials: D
authors.lastname: Pernet
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Laplante
authors.forename: Laurence
authors.initials: L
authors.lastname: Millon
authors.forename: Renaud
authors.initials: R
authors.lastname: Piarroux
mesh_terms: D000383:Agriculture; D016022:Case-Control Studies; D005203:Farmer's Lung / Q000382:microbiology*; D006801:Humans; D016273:Occupational Exposure; D006109:Poaceae / Q000382:microbiology*; D018709:Statistics, Nonparametric