Clinical Burden associated with Different Viruses
The median LOS, the proportion of subjects admitted to an ICU, the ICU LOS, and in-hospital mortality for each virus are shown in Table 2. As the burden was similar in each year, data for both years were combined. The overall median LOS was 4.2 days (interquartile range [IQR] 2.3, 7.8 days) and similar for each virus. Overall, 14.4% of patients had an ICU admission with a median ICU LOS of 4.0 days (IQR 2.1, 8.4 days). Compared to other viruses, CoV229E (p=0.01) and AV (p=0.02) were each associated with a significantly larger proportion of ICU admissions and AV was associated with the longest ICU LOS (p=0.03). Of the 225 ICU admissions associated with RV/EV, 19 (8.4%) had another virus co-detected. Four percent of patients died during hospitalization. RV/EV was associated with 31.8% of deaths and CoV229E was associated with the highest mortality rate (12.3%, p < 0.001). The median LOS among those who died was 9.7 days (IQR 5.0, 19.8 days) and was longest for AV (38.0 days, p=0.03).
Those with RV/EV (n=1,667 patients) and those with influenza/non-influenza co-detection (n=67 patients) were excluded from the analysis comparing the burden of influenza viruses (784 patients) to that of the non-influenza viruses (1,714 patients). Compared to patients with influenza, a significantly higher proportion of patients with the non-influenza viruses CoV, RSV, PIV, hMPV, and AV were admitted to the ICU (11.0% vs. 16.7%, respectively, p=0.002). Compared to patients with influenza, a significantly higher proportion of patients with the non-influenza respiratory viruses died (3.2% and 5.2%, respectively, p=0.025).