ABSTRACT
BackgroundSince the onset of the COVID-19 pandemic, the disease has frequently been compared with seasonal influenza, but this comparison is based on little empirical data.AimThis study compares in-hospital outcomes for patients with community-acquired COVID-19 and patients with community-acquired influenza in Switzerland.MethodsThis retrospective multi-centre cohort study includes patients > 18 years admitted for COVID-19 or influenza A/B infection determined by RT-PCR. Primary and secondary outcomes were in-hospital mortality and intensive care unit (ICU) admission for patients with COVID-19 or influenza. We used Cox regression (cause-specific and Fine-Gray subdistribution hazard models) to account for time-dependency and competing events with inverse probability weighting to adjust for confounders.ResultsIn 2020, 2,843 patients with COVID-19 from 14 centres were included. Between 2018 and 2020, 1,381 patients with influenza from seven centres were included; 1,722 (61%) of the patients with COVID-19 and 666 (48%) of the patients with influenza were male (p < 0.001). The patients with COVID-19 were younger (median 67 years; interquartile range (IQR): 54-78) than the patients with influenza (median 74 years; IQR: 61-84) (p < 0.001). A larger percentage of patients with COVID-19 (12.8%) than patients with influenza (4.4%) died in hospital (p < 0.001). The final adjusted subdistribution hazard ratio for mortality was 3.01 (95% CI: 2.22-4.09; p < 0.001) for COVID-19 compared with influenza and 2.44 (95% CI: 2.00-3.00, p < 0.001) for ICU admission.ConclusionCommunity-acquired COVID-19 was associated with worse outcomes compared with community-acquired influenza, as the hazards of ICU admission and in-hospital death were about two-fold to three-fold higher.
Subject(s)
COVID-19 , Influenza, Human , Cohort Studies , Hospital Mortality , Hospitalization , Hospitals , Humans , Influenza, Human/diagnosis , Influenza, Human/epidemiology , Intensive Care Units , Male , Pandemics , Retrospective Studies , SARS-CoV-2 , Switzerland/epidemiologyABSTRACT
The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.