TY  - JOUR
AU  - Denis, Fabrice
AU  - Galmiche, Simon
AU  - Dinh, Aurélien
AU  - Fontanet, Arnaud
AU  - Scherpereel, Arnaud
AU  - Benezit, Francois
AU  - Lescure, François-Xavier
PY  - 2020
DA  - 2020/6/11
TI  - Epidemiological Observations on the Association Between Anosmia and COVID-19 Infection: Analysis of Data From a Self-Assessment Web Application
JO  - J Med Internet Res
SP  - e19855
VL  - 22
IS  - 6
KW  - COVID-19
KW  - anosmia
KW  - epidemiological surveillance
KW  - self-assessment
KW  - web application
KW  - outbreak
KW  - symptoms
KW  - surveillance
KW  - epidemiology
AB  - 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 
SN  - 1438-8871
UR  - http://www.jmir.org/2020/6/e19855/
UR  - https://doi.org/10.2196/19855
UR  - http://www.ncbi.nlm.nih.gov/pubmed/32496206
DO  - 10.2196/19855
ID  - info:doi/10.2196/19855
ER  -