title: Individual and environmental factors associated with the seroprevalence ofBorrelia burgdorferiin Belgian farmers and veterinarians.
abstract: BACKGROUND
  Lyme disease (LD) is a common tick-borne disease in Europe. Diverse factors at various scales determine the spatial distribution ofBorrelia burgdorferiinfection risk and a better understanding of those factors in a spatially explicit framework is needed for disease management and prevention. While the ecology of ticks and the landscape favoring their abundance have been extensively studied, the environmental conditions favoring an intense contact with susceptible humans, including groups at risk, are sparse. The aim of this study is to assess which individual and environmental factors can favorB. burgdorferiinfection in a Belgian group professionally at risk.
  
  
  METHODS
  Serological results of 127 veterinarians and farmers enrolled in this study were analyzed, taking into account their municipality of residence. Using binary logistic regression and considering interaction terms, the joint effects of landscape composition and configuration, and forest and wildlife management were examined.
  
  
  RESULTS
  Seven of the 127 workers were seropositive for LD, leading to a seroprevalence of 5.51%. Seropositivity was higher in older persons. The proportion of forest and semi-natural habitats and wetland had a positive impact on LD seroprevalence while arable land-grassland ecotones had a negative one. Our results confirmed the need to consider complex interactions between landscape variables in order to model risk.
  
  
  CONCLUSIONS
  Our data show that LD has to be considered as a risk for farmers and veterinarians. Rather than focusing either on ecological aspects of tick and pathogen distribution or on purely epidemiological aspects such as individual risk factors, our model highlights the role of human-environment interactions in LD risk assessment.
authors.affiliation: Earth and Life Institute (ELI), Georges Lemaitre Center for Earth and Climate Research, Université catholique de Louvain (UCL), Louvain-la-Neuve, Belgique.|Pôle Epidémiologie et Biostatistique, Institut de Recherche Expérimentale et Clinique (IREC), Faculté de Santé Publique (FSP), Université catholique de Louvain (UCL), Bruxelles, Belgique; mathilde.dekeukeleire@uclouvain.be.
authors.forename: Mathilde
authors.initials: M
authors.lastname: De Keukeleire
authors.affiliation: Pôle Epidémiologie et Biostatistique, Institut de Recherche Expérimentale et Clinique (IREC), Faculté de Santé Publique (FSP), Université catholique de Louvain (UCL), Bruxelles, Belgique.
authors.forename: Annie
authors.initials: A
authors.lastname: Robert
authors.affiliation: Division of Clinical Biology, Cliniques Universitaires Saint-Luc, Université catholique de Louvain (UCL), Bruxelles, Belgique.
authors.forename: Benoît
authors.initials: B
authors.lastname: Kabamba
authors.affiliation: ARSIA (Association Régionale de Santé et d'Identification Animales), Ciney, Belgique.
authors.forename: Elise
authors.initials: E
authors.lastname: Dion
authors.affiliation: Pôle Epidémiologie et Biostatistique, Institut de Recherche Expérimentale et Clinique (IREC), Faculté de Santé Publique (FSP), Université catholique de Louvain (UCL), Bruxelles, Belgique.
authors.forename: Victor
authors.initials: V
authors.lastname: Luyasu
authors.affiliation: Earth and Life Institute (ELI), Georges Lemaitre Center for Earth and Climate Research, Université catholique de Louvain (UCL), Louvain-la-Neuve, Belgique.
authors.forename: Sophie O
authors.initials: SO
authors.lastname: Vanwambeke
keywords: B. burgdorferi infection; Belgium; Lyme disease; risk assessment; spatial modeling