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Participatory surveillance systems provide rich crowdsourced data, profiling individuals and their health status at a given time. We explored the usefulness of data from GrippeNet.fr, a participatory surveillance system, to estimate influenza-related illness incidence in France. GrippeNet.fr is an online cohort since 2012 averaging ca. 5,000 weekly participants reporting signs/symptoms suggestive of influenza. GrippeNet.fr has flexible criteria to define influenza-related illness. Different case definitions based on reported signs/symptoms and inclusions of criteria accounting for individuals’ reporting and participation were used to produce influenza-related illness incidence estimates, which were compared to those from sentinel networks. We focused on the 2012/13 and 2013/14 seasons when two sentinel networks, monitoring influenza-like-illness (ILI) and acute respiratory infections (ARI) existed in France. : GrippeNet.fr incidence estimates agreed well with official temporal trends, with a higher accuracy for ARI than ILI. The influenza epidemic peak was often anticipated by one week, despite irregular participation of individuals. The European Centre for Disease Prevention and Control ILI definition, commonly used by participatory surveillance in Europe, performed better in tracking ARI than ILI when applied to GrippeNet.fr data. : Evaluation of the epidemic intensity from crowdsourced data requires epidemic and intensity threshold estimations from several consecutive seasons. The study provides a standardised analytical framework for crowdsourced surveillance showing high sensitivity in detecting influenza-related changes in the population. It contributes to improve the comparability of epidemics across seasons and with sentinel systems. In France, GrippeNet.fr may supplement the ILI sentinel network after ARI surveillance discontinuation in 2014.


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  1. World Health Organization (WHO). WHO global technical consultation: global standards and tools for influenza surveillance, 8-10 March 2011. Geneva: WHO; 2011. [Accessed 3 May 2017]. Available from: http://www.who.int/influenza/resources/documents/technical_consultation/en/
  2. Influenzanet. 2013. [Accessed 6 Sep 2016]. Available from: http://www.influenzanet.eu/
  3. Flu Tracking. 2007. [Accessed 6 Sep 2016]. Available from: http://www.flutracking.net/
  4. Reporta. 2009. [Accessed 6 Sep 2016]. Available from: http://reporta.c3.org.mx/
  5. Smolinski MS, Crawley AW, Baltrusaitis K, Chunara R, Olsen JM, Wójcik O, et al. Flu Near You: Crowdsourced Symptom Reporting Spanning 2 Influenza Seasons. Am J Public Health. 2015;105(10):2124-30.  https://doi.org/10.2105/AJPH.2015.302696  PMID: 26270299 
  6. Salud Boricua. 2012. [Accessed 6 Sep 2016]. Available from: https://saludboricua.org/
  7. Dugas AF, Jalalpour M, Gel Y, Levin S, Torcaso F, Igusa T, et al. Influenza forecasting with Google Flu Trends. PLoS One. 2013;8(2):e56176.  https://doi.org/10.1371/journal.pone.0056176  PMID: 23457520 
  8. Salathé M, Bengtsson L, Bodnar TJ, Brewer DD, Brownstein JS, Buckee C, et al. Digital epidemiology. PLOS Comput Biol. 2012;8(7):e1002616.  https://doi.org/10.1371/journal.pcbi.1002616  PMID: 22844241 
  9. Wójcik OP, Brownstein JS, Chunara R, Johansson MA. Public health for the people: participatory infectious disease surveillance in the digital age. Emerg Themes Epidemiol. 2014;11(1):7.  https://doi.org/10.1186/1742-7622-11-7  PMID: 24991229 
  10. Guerrisi C, Turbelin C, Blanchon T, Hanslik T, Bonmarin I, Levy-Bruhl D, et al. Participatory syndromic surveillance of influenza in Europe. J Infect Dis. 2016;214(suppl_4):S386-92.  https://doi.org/10.1093/infdis/jiw280  PMID: 28830105 
  11. Paolotti D, Carnahan A, Colizza V, Eames K, Edmunds J, Gomes G, et al. Web-based participatory surveillance of infectious diseases: the Influenzanet participatory surveillance experience. Clin Microbiol Infect. 2014;20(1):17-21.  https://doi.org/10.1111/1469-0691.12477  PMID: 24350723 
  12. Friesema IHM, Koppeschaar CE, Donker GA, Dijkstra F, van Noort SP, Smallenburg R, et al. Internet-based monitoring of influenza-like illness in the general population: experience of five influenza seasons in The Netherlands. Vaccine. 2009;27(45):6353-7.  https://doi.org/10.1016/j.vaccine.2009.05.042  PMID: 19840672 
  13. Vandendijck Y, Faes C, Hens N. Eight years of the Great Influenza Survey to monitor influenza-like illness in Flanders. PLoS One. 2013;8(5):e64156.  https://doi.org/10.1371/journal.pone.0064156  PMID: 23691162 
  14. Kjelsø C, Galle M, Bang H, Ethelberg S, Krause TG. Influmeter - an online tool for self-reporting of influenza-like illness in Denmark. Infect Dis (Lond). 2016;48(4):322-7.  https://doi.org/10.3109/23744235.2015.1122224  PMID: 26654752 
  15. Adler AJ, Eames KT, Funk S, Edmunds WJ. Incidence and risk factors for influenza-like-illness in the UK: online surveillance using Flusurvey. BMC Infect Dis. 2014;14(1):232.  https://doi.org/10.1186/1471-2334-14-232  PMID: 24885043 
  16. Casalegno JS, Eibach D, Valette M, Enouf V, Daviaud I, Behillil S, et al. Performance of influenza case definitions for influenza community surveillance: based on the French influenza surveillance network GROG, 2009-2014. Euro Surveill. 2017;22(14):30504.  https://doi.org/10.2807/1560-7917.ES.2017.22.14.30504  PMID: 28422004 
  17. Jiang L, Lee VJ, Lim WY, Chen MI, Chen Y, Tan L, et al. Performance of case definitions for influenza surveillance. Euro Surveill. 2015;20(22):21145.  https://doi.org/10.2807/1560-7917.ES2015.20.22.21145  PMID: 26062645 
  18. Aguilera JF, Paget WJ, Mosnier A, Heijnen ML, Uphoff H, van der Velden J, et al. Heterogeneous case definitions used for the surveillance of influenza in Europe. Eur J Epidemiol. 2003;18(8):751-4.  https://doi.org/10.1023/A:1025337616327  PMID: 12974549 
  19. Debin M, Turbelin C, Blanchon T, Bonmarin I, Falchi A, Hanslik T, et al. Evaluating the feasibility and participants’ representativeness of an online nationwide surveillance system for influenza in France. PLoS One. 2013;8(9):e73675.  https://doi.org/10.1371/journal.pone.0073675  PMID: 24040020 
  20. Ariza M, Guerrisi C, Souty C, Rossignol L, Turbelin C, Hanslik T, et al. Healthcare-seeking behaviour in case of influenza-like illness in the French general population and factors associated with a GP consultation: an observational prospective study. BJGP Open.2017;1(4).
  21. Boiron K, Sarazin M, Debin M, Raude J, Rossignol L, Guerrisi C, et al. Opinion about seasonal influenza vaccination among the general population 3 years after the A(H1N1)pdm2009 influenza pandemic. Vaccine. 2015;33(48):6849-54.  https://doi.org/10.1016/j.vaccine.2015.08.067  PMID: 26322844 
  22. Flahault A, Blanchon T, Dorléans Y, Toubiana L, Vibert JF, Valleron AJ. Virtual surveillance of communicable diseases: a 20-year experience in France. Stat Methods Med Res. 2006;15(5):413-21.  https://doi.org/10.1177/0962280206071639  PMID: 17089946 
  23. Mosnier A, Caini S, Daviaud I, Bensoussan JL, Stoll-Keller F, Bui TT, et al. GROG network. Ten influenza seasons in France: distribution and timing of influenza A and B circulation, 2003-2013. BMC Infect Dis. 2015;15(1):357.  https://doi.org/10.1186/s12879-015-1056-z  PMID: 26289794 
  24. Vergu E, Grais RF, Sarter H, Fagot JP, Lambert B, Valleron AJ, et al. Medication sales and syndromic surveillance, France. Emerg Infect Dis. 2006;12(3):416-21.  https://doi.org/10.3201/eid1203.050573  PMID: 16704778 
  25. European Centre for Disease Prevention and Control (ECDC). Influenza case definitions. 2016. [Accessed 6 Sep 2016]. Stockholm: ECDC. Available from: http://ecdc.europa.eu/en/healthtopics/influenza/surveillance/Pages/influenza_case_definitions.asp
  26. Bayer C, Remschmidt C, an der Heiden M, Tolksdorf K, Herzhoff M, Kaersten S, et al. Internet-based syndromic monitoring of acute respiratory illness in the general population of Germany, weeks 35/2011 to 34/2012. Euro Surveill. 2014;19(4):20684.  https://doi.org/10.2807/1560-7917.ES2014.19.4.20684  PMID: 24507468 
  27. Core R. Teal and contributors worldwide. The R Stats Package. Available from: https://stat.ethz.ch/R-manual/R-devel/library/stats/html/filter.html.
  28. Vega T, Lozano JE, Meerhoff T, Snacken R, Beauté J, Jorgensen P, et al. Influenza surveillance in Europe: comparing intensity levels calculated using the moving epidemic method. Influenza Other Respi Viruses. 2015;9(5):234-46.  https://doi.org/10.1111/irv.12330  PMID: 26031655 
  29. Wenham C, Gray ER, Keane CE, Donati M, Paolotti D, Pebody R, et al. Self-Swabbing for Virological Confirmation of Influenza-Like Illness Among an Internet-Based Cohort in the UK During the 2014-2015 Flu Season: Pilot Study. J Med Internet Res. 2018;20(3):e71.  https://doi.org/10.2196/jmir.9084  PMID: 29496658 
  30. Jackson ML, Nguyen M, Kirlin B, Madziwa L. Self-Collected Nasal Swabs for Respiratory Virus Surveillance. Open Forum Infect Dis. 2015;2(4):ofv152.  https://doi.org/10.1093/ofid/ofv152  PMID: 26613095 
  31. Goyal S, Prasert K, Praphasiri P, Chittaganpitch M, Waicharoen S, Ditsungnoen D, et al. The acceptability and validity of self-collected nasal swabs for detection of influenza virus infection among older adults in Thailand. Influenza Other Respi Viruses. 2017;11(5):412-7.  https://doi.org/10.1111/irv.12471  PMID: 28741903 
  32. World Health Organization (WHO). WHO Regional Office for Europe guidance for sentinel influenza surveillance in humans. 2011. Geneva: WHO. [Accessed 15 Apr 2015]. Available from: http://www.euro.who.int/__data/assets/pdf_file/0020/90443/E92738.pdf?ua=1
  33. Rehn M, Carnahan A, Merk H, Kühlmann-Berenzon S, Galanis I, Linde A, et al. Evaluation of an Internet-based monitoring system for influenza-like illness in Sweden. PLoS One. 2014;9(5):e96740.  https://doi.org/10.1371/journal.pone.0096740  PMID: 24824806 

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