title: Health Care Professionals' Evidence-Based Medicine Internet Searches Closely Mimic the Known Seasonal Variation of Lyme Borreliosis: A Register-Based Study.
abstract: BACKGROUND
  Both health care professionals and nonprofessionals seek medical information on the Internet. Using Web-based search engine searches to detect epidemic diseases has, however, been problematic. Physician's databases (PD) is a chargeable evidence-based medicine (EBM) portal on the Internet for health care professionals and is available throughout the entire health care system in Finland. Lyme borreliosis (LB), a well-defined disease model, shows temporal and regional variation in Finland. Little data exist on health care professionals' searches from Internet-based EBM databases in public health surveillance.
  
  
  OBJECTIVE
  The aim of this study was to assess whether health care professionals' use of Internet EBM databases could describe seasonal increases of the disease and supplement routine public health surveillance.
  
  
  METHODS
  Two registers, PD and the register of primary health care diagnoses (Avohilmo), were used to compare health care professionals' Internet searches on LB from EBM databases and national register-based LB diagnoses in order to evaluate annual and regional variations of LB in the whole country and in three selected high-incidence LB regions in Finland during 2011-2015.
  
  
  RESULTS
  Both registers, PD and Avohilmo, show visually similar patterns in annual and regional variation of LB in Finland and in the three high-incidence LB regions during 2011-2015.
  
  
  CONCLUSIONS
  Health care professionals' Internet searches from EBM databases coincide with national register diagnoses of LB. PD searches showed a clear seasonal variation. In addition, notable regional differences were present in both registers. However, physicians' Internet medical searches should be considered as a supplementary source of information for disease surveillance.
authors.affiliation: University of Helsinki, Helsinki, Finland.|National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Samuli
authors.identifier: http://orcid.org/0000-0002-6090-1367
authors.initials: S
authors.lastname: Pesälä
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Mikko J
authors.identifier: http://orcid.org/0000-0003-4120-4432
authors.initials: MJ
authors.lastname: Virtanen
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Jussi
authors.identifier: http://orcid.org/0000-0001-6590-9520
authors.initials: J
authors.lastname: Sane
authors.affiliation: Duodecim Medical Publications Ltd, Helsinki, Finland.
authors.forename: Jukkapekka
authors.identifier: http://orcid.org/0000-0003-0007-5494
authors.initials: J
authors.lastname: Jousimaa
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Outi
authors.identifier: http://orcid.org/0000-0002-6449-1721
authors.initials: O
authors.lastname: Lyytikäinen
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Satu
authors.identifier: http://orcid.org/0000-0001-8842-9570
authors.initials: S
authors.lastname: Murtopuro
authors.affiliation: Duodecim Medical Publications Ltd, Helsinki, Finland.
authors.forename: Pekka
authors.identifier: http://orcid.org/0000-0002-5077-7788
authors.initials: P
authors.lastname: Mustonen
authors.affiliation: Public Health Medicine, Helsinki University Hospital, University of Helsinki, Helsinki, Finland.
authors.forename: Minna
authors.identifier: http://orcid.org/0000-0002-9645-4925
authors.initials: M
authors.lastname: Kaila
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.|Children's Hospital, Helsinki University Hospital, University of Helsinki, Helsinki, Finland.
authors.forename: Otto
authors.identifier: http://orcid.org/0000-0001-6254-3180
authors.initials: O
authors.lastname: Helve
keywords: Lyme borreliosis; evidence-based medicine; information systems; public health surveillance; search engine