Enhanced surveillance of COVID-19 in secondary care in Europe: a tale of two waves

Background: The I-MOVE-COVID-19 Consortium was established to conduct surveillance of hospitalised COVID-19 cases in nine European countries, aiming to describe the clinical and epidemiological characteristics of severe COVID-19 in order to inform public health response. Methods: Data are pooled from 11 participating sites; two (England and Scotland) submitting national data, with the remainder being from a selection of hospitals. Descriptive analysis is performed on the pooled dataset overall and comparing data on patients admitted from week 5 to 28 of 2020 (“first wave”) vs those admitted later (“second wave”). Results: Data on 84,297 hospitalised patients were submitted for 01 February 2020 - 31 January 2021. Fifty-six percent of cases (46,907/84,193) were male and median age was 69 years. Where information was available, 44% (25,344 /57,769) patients were recorded as having at least one chronic condition. Ninety-five percent (7,868/8,270 and 90% (5,606/6,231) were reported with respiratory and febrile presentations respectively. Twenty-four percent (18,795/78,955) were admitted to intensive care units (ICU) and 26% (19,805/76,764) died in hospital (all sites); 12% (3,305/28,262) and 20% (5,454/27,066) respectively for all sites except England (where ICU reporting is mandated, biasing the dataset towards more severe outcomes as this site represents >50% of all cases). As a percentage of all hospital admissions, both ICU admissions and deaths decreased significantly between the first and second waves in both sexes and across all age- groups, apart from the over 75s. Conclusions: Results from this multicentre European surveillance system suggest that about one in 10 hospitalised COVID-19 patients are admitted to ICU and one in five have fatal outcomes. Fatality and ICU admission were lower in the second wave compared with the first.The I-MOVE-COVID-19 network has received funding from the European Commission (from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 101003673).N/