title: Improved correlation of human Q fever incidence to modelled C. burnetii concentrations by means of an atmospheric dispersion model.
abstract: BACKGROUND
  Atmospheric dispersion models (ADMs) may help to assess human exposure to airborne pathogens. However, there is as yet limited quantified evidence that modelled concentrations are indeed associated to observed human incidence.
  
  
  METHODS
  We correlated human Q fever (caused by the bacterium Coxiella burnetii) incidence data in the Netherlands to modelled concentrations from three spatial exposure models: 1) a NULL model with a uniform concentration distribution, 2) a DISTANCE model with concentrations proportional to the distance between the source and residential addresses of patients, and 3) concentrations modelled by an ADM using three simple emission profiles. We used a generalized linear model to correlate the observed incidences to modelled concentrations and validated it using cross-validation.
  
  
  RESULTS
  ADM concentrations generally correlated the best to the incidence data. The DISTANCE model always performed significantly better than the NULL model. ADM concentrations based on wind speeds exceeding threshold values of 0 and 2 m/s performed better than those based on 4 or 6 m/s. This might indicate additional exposure to bacteria originating from a contaminated environment.
  
  
  CONCLUSIONS
  By adding meteorological information the correlation between modelled concentration and observed incidence improved, despite using three simple emission profiles. Although additional information is needed - especially regarding emission data - these results provide a basis for the use of ADMs to predict and to visualize the spread of airborne pathogens during livestock, industry and even bio-terroristic related outbreaks or releases to a surrounding human population.
authors.affiliation: Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, P.O. Box 80163, 3508, TD, Utrecht, The Netherlands. jeroen.van.leuken@rivm.nl.|Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands. jeroen.van.leuken@rivm.nl.
authors.forename: Jeroen P G
authors.initials: JP
authors.lastname: van Leuken
authors.affiliation: Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands. jan.van.de.kassteele@rivm.nl.
authors.forename: Jan
authors.initials: J
authors.lastname: van de Kassteele
authors.affiliation: Environmental Safety (M&V), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands. ferd.sauter@rivm.nl.
authors.forename: Ferd J
authors.initials: FJ
authors.lastname: Sauter
authors.affiliation: Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands. wim.van.der.hoek@rivm.nl.
authors.forename: Wim
authors.initials: W
authors.lastname: van der Hoek
authors.affiliation: Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, P.O. Box 80163, 3508, TD, Utrecht, The Netherlands. d.heederik@uu.nl.
authors.forename: Dick
authors.initials: D
authors.lastname: Heederik
authors.affiliation: Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, P.O. Box 80163, 3508, TD, Utrecht, The Netherlands. ariehavelaar@icloud.com.|Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands. ariehavelaar@icloud.com.|Emerging Pathogens Institute, University of Floriday, Gainesville, Florida, USA. ariehavelaar@icloud.com.
authors.forename: Arie H
authors.initials: AH
authors.lastname: Havelaar
authors.affiliation: Centre for Infectious Disease Control (CIb), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720, BA, Bilthoven, The Netherlands. arno.swart@rivm.nl.
authors.forename: Arno N
authors.initials: AN
authors.lastname: Swart
mesh_terms: D001272:Atmosphere / Q000032:analysis*; D016997:Coxiella burnetii / Q000302:isolation & purification*; D006801:Humans; D015994:Incidence; D008962:Models, Theoretical; D009426:Netherlands / Q000453:epidemiology; D011156:Population Density; D011778:Q Fever / Q000175:diagnosis / Q000453:epidemiology*