1 Divisions of Critical Care and Pulmonology, Department of Medicine, Charlotte Maxeke Johannesburg Academic Hospital and Faculty of Health Sciences, University of Witwatersrand, Johannesburg, South Africa.
2 Division of Infection and Immunity, University College London Medical School and NIHR Biomedical Research Center, University College of London Hospitals, London, UK.
3 Department of Anesthesiology and Intensive Care Medicine, Kepler University Hospital, Johannes Kepler University Linz, Linz, Austria. Martin.Duenser@kepleruniklinikum.at.