Lessons from COVID-19 syndromic surveillance through emergency department activity: a prospective time series study from western Switzerland.

OBJECTIVE: We aimed to assess if emergency department (ED) syndromic surveillance during the first and second waves of the COVID-19 outbreak could have improved our surveillance system. DESIGN AND SETTINGS: We did an observational study using aggregated data from the ED of a university hospital and public health authorities in western Switzerland. PARTICIPANTS: All patients admitted to the ED were included. PRIMARY OUTCOME MEASURE: The main outcome was intensive care unit (ICU) occupancy. We used time series methods for ED syndromic surveillance (influenza-like syndrome, droplet isolation) and usual indicators from public health authorities (new cases, proportion of positive tests in the population). RESULTS: Based on 37 319 ED visits during the COVID-19 outbreak, 1421 ED visits (3.8%) were positive for SARS-CoV-2. Patients with influenza-like syndrome or droplet isolation in the ED showed a similar correlation to ICU occupancy as confirmed cases in the general population, with a time lag of approximately 13 days (0.73, 95% CI 0.64 to 0.80; 0.79, 95% CI 0.71 to 0.86; and 0.76, 95% CI 0.67 to 0.83, respectively). The proportion of positive tests in the population showed the best correlation with ICU occupancy (0.95, 95% CI 0.85 to 0.96). CONCLUSION: ED syndromic surveillance is an effective tool to detect and monitor a COVID-19 outbreak and to predict hospital resource needs. It would have allowed to anticipate ICU occupancy by 13 days, including significant aberration detection at the beginning of the second wave.

Emergency department : COVID-19 crisis and organizational aspects / Urgences hospitalieres : crise COVID-19 et aspects organisationnels

Emergency departments are on the front line in the management of COVID-19 cases, from screening to the initial management of the most severe cases. The clinical presentation of COVID-19 range from non-specific symptoms to adult acute respiratory distress syndrome (ARDS). Diagnosis is based on PCR from a nasopharyngeal swab and emergency treatment rely on oxygen therapy. Patient's orientation (home, hospitalization, admission in intensive care unit) is a central aspect of emergency management. The shift from a strategy of systematic recognition of potential cases to the one of epidemic mitigation required hospital emergency medicine services to implement crisis management measures, to guarantee admission and hospitalization capacity. Les services durgences sont en premiere ligne dans la gestion des cas de COVID-19, quil sagisse du depistage ou de la prise en charge des cas les plus severes. La clinique associee au COVID-19 va de symptomes non specifiques au syndrome de detresse respiratoire aigue de ladulte. Le diagnostic repose sur la PCR a partir dun frottis nasopharynge et le traitement durgence sur loxygenotherapie. Lorientation du patient (retour a domicile, hospitalisation, indication aux soins intensifs) est un aspect central de la prise en charge aux urgences. Le passage de la strategie de reconnaissance systematique des cas potentiels a celle de la mitigation de lepidemie a implique pour les services durgences hospitaliers la mise en place de mesures exceptionnelles afin de garantir une capacite daccueil et dhospitalisation.