Kaplan-Meier curve on length of ICU stay in IAPA (blue) and non-IAPA patients (red). Probability to stay in the ICU is shown on x-axis, time after admission to ICU are shown on y-axis, p<0.001. IAPA = influenza-associated pulmonary aspergillosis, non-IAPA = influenza infection without IAPA, ICU = intensive-care unit