title: The role of fungal spores in thunderstorm asthma.
abstract: OBJECTIVE
  To document the existence and investigate the etiology of "thunderstorm asthma," which has been reported sporadically over the past 20 years.
  
  
  METHODS
  We assessed the relationship between thunderstorms, air pollutants, aeroallergens, and asthma admissions to a children's hospital emergency department over a 6-year period.
  
  
  RESULTS
  During thunderstorm days (n = 151 days) compared to days without thunderstorms (n = 919 days), daily asthma visits increased from 8.6 to 10 (p < 0.05), and air concentrations of fungal spores doubled (from 1,512 to 2,749/m(3)), with relatively smaller changes in pollens and air pollutants. Daily time-series analyses across the 6 years of observation, irrespective of the presence or absence of thunderstorms, demonstrated that an increase in total spores, equivalent to its seasonal mean, was associated with a 2.2% (0.9% SE) increase in asthma visits.
  
  
  CONCLUSIONS
  Our results support a relationship between thunderstorms and asthma, and suggest that the mechanism may be through increases in spores that exacerbate asthma. Replication in other climates is suggested to determine whether these findings can be generalized to other aeroallergen mixes.
authors.affiliation: University of Ottawa Health Research Institute, Ottawa, Ontario, Canada. rdales@ottawahospital.on.ca
authors.forename: Robert E
authors.initials: RE
authors.lastname: Dales
authors.forename: Sabit
authors.initials: S
authors.lastname: Cakmak
authors.forename: Stan
authors.initials: S
authors.lastname: Judek
authors.forename: Tom
authors.initials: T
authors.lastname: Dann
authors.forename: Frances
authors.initials: F
authors.lastname: Coates
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Brook
authors.forename: Richard T
authors.initials: RT
authors.lastname: Burnett
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000276:immunology*; D001249:Asthma / Q000453:epidemiology / Q000382:microbiology*; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D006801:Humans; D009864:Ontario / Q000453:epidemiology; D011058:Pollen; D011891:Rain; D012044:Regression Analysis; D012307:Risk Factors; D012621:Seasons; D013172:Spores, Fungal / Q000276:immunology*
chemical_list: D000393:Air Pollutants