1. Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialities, University of Palermo, 90127 Palermo, Italy
2. Legionella Reference Laboratory, University of Palermo, 90127 Palermo, Italy
3. Sicilian Health Department, Public Health and Environmental Risks Service, 90127 Palermo, Italy
4. Laboratory of Microbiology, A. O. Ospedali Riuniti “Villa Sofia-Cervello”, 90100 Palermo, Italy