%0 Journal Article
%@ 1438-8871
%I JMIR Publications
%V 22
%N 6
%P e19855
%T Epidemiological Observations on the Association Between Anosmia and COVID-19 Infection: Analysis of Data From a Self-Assessment Web Application
%A Denis,Fabrice
%A Galmiche,Simon
%A Dinh,Aurélien
%A Fontanet,Arnaud
%A Scherpereel,Arnaud
%A Benezit,Francois
%A Lescure,François-Xavier
%+ Inter-regional Cancer Institut Jean Bernard, 9, rue Beauverger, Le Mans, 72100, France, 33 243475810, f.denis@cjb72.org
%K COVID-19
%K anosmia
%K epidemiological surveillance
%K self-assessment
%K web application
%K outbreak
%K symptoms
%K self-assessment
%K surveillance
%K epidemiology
%D 2020
%7 11.6.2020
%9 Original Paper
%J J Med Internet Res
%G English
%X Background: We developed a self-assessment and participatory surveillance web application for coronavirus disease (COVID-19), which was launched in France in March 2020. Objective: Our objective was to determine if self-reported symptoms could help monitor the dynamics of the COVID-19 outbreak in France. Methods: Users were asked questions about underlying conditions, sociodemographic status, zip code, and COVID-19 symptoms. Depending on the symptoms reported and the presence of coexisting disorders, users were told to either stay at home, contact a general practitioner (GP), or call an emergency phone number. Data regarding COVID-19–related hospitalizations were retrieved from the Ministry of Health. Results: As of March 29, 2020, the application was opened 4,126,789 times; 3,799,535 electronic questionnaires were filled out; and 2,477,174 users had at least one symptom. In total, 34.8% (n=1,322,361) reported no symptoms. The remaining users were directed to self-monitoring (n=858,878, 22.6%), GP visit or teleconsultation (n=1,033,922, 27.2%), or an emergency phone call (n=584,374, 15.4%). Emergency warning signs were reported by 39.1% of participants with anosmia, a loss of the sense of smell (n=127,586) versus 22.7% of participants without anosmia (n=1,597,289). Anosmia and fever and/or cough were correlated with hospitalizations for COVID-19 (Spearman correlation coefficients=0.87 and 0.82, respectively; P<.001 for both). Conclusions: This study suggests that anosmia may be strongly associated with COVID-19 and its severity. Despite a lack of medical assessment and virological confirmation, self-checking application data could be a relevant tool to monitor outbreak trends. Trial Registration: ClinicalTrials.gov NCT04331171; https://clinicaltrials.gov/ct2/show/NCT04331171 
%M 32496206
%R 10.2196/19855
%U http://www.jmir.org/2020/6/e19855/
%U https://doi.org/10.2196/19855
%U http://www.ncbi.nlm.nih.gov/pubmed/32496206