1 Department of Respiratory Medicine, Hospital Universitario de Gran Canaria Dr. Negrín, Las Palmas de Gran Canaria, Spain. Electronic address: jvalgal@gmail.com.
2 Professor of Medicine, Department of Medical and Surgical Sciences, School of Medicine, University of Las Palmas de Gran Canaria, Spain.
3 Intensive Care Unit, Hospital Universitario de Gran Canaria Dr. Negrín, Las Palmas de Gran Canaria, Spain.
4 Department of Immunology, Hospital Universitario de Gran Canaria Dr. Negrín, Las Palmas de Gran Canaria, Spain.