Transmission, start of symptom and morbidity among Danish COVID-19 patients admitted to hospital.

Meyer, Christian N

INTRODUCTION We explored transmission of the coronavirus disease 2019 (COVID-19) in severely ill patients and analysed the relationship between co-morbidity and mortality or the need for intensive care unit (ICU) care. METHODS Clinical data, treatment and outcome were analysed in this retrospective study of 101 consecutive patients with COVID-19 admitted to a regional Danish hospital from 2 March 2020, based on data from electronic medical records. RESULTS The mean age was 71.8 years, 33% were never smokers and 82% had one or more predefined chronic diseases. In-hospital mortality was 30%, and 20% of the patients were offered ICU care. In ICU patients, we found a male preponderance (88% versus 44%, p = 0.006), but death (50% versus 25%, p = 0.053) and other pre-defined co-morbidities did not differ significantly from non-ICU patients. The source of infection was unknown in 74% of patients, related to endemic travel in 10%, hospital acquired in 6% and related to close acquaintances in 11%. COVID-19-related symptoms were initially observed from February 21 (week 8 and week 9) in the first three patients who had no known source of infection. We found that 7% of cases had an increased risk of in-hospital transmission, based on a 7-16 days delay in coronavirus testing. CONCLUSIONS The frequency of co-morbidity in hospital-admitted COVID-19 patients and the correlation to death and ICU attendance were analysed. In all, 74% of the infection cases were of unknown source during the first weeks of the epidemic, which points to considerable community transmission and possibly pre- or asymptomatic transmission, also several weeks before 21 February 2020. FUNDING none. TRIAL REGISTRATION not relevant after correspondence with the Ethics Committee of Region Zealand. Furthermore, permission was granted from The Danish Data Protection Agency, Region Zealand (REG-070-2020).