Prevalence and Virulence Profiles of Legionella Species: Isolated from Cancer Patients Hospital Environments

Legionella pneumophila serogroup 1 is the leading cause of human legionellosis and is associated with intracellular survival in alveolar macrophages. This study investigated the occurrence and characteristics of Legionella spp. among cancer patients and hospital environments at the Oncology Center of Al-Sadr Hospital, Basra, Iraq. A total of 360 samples (271 clinical and 89 environmental) were collected between January and March 2020. Presumptive isolates were identified using culture on BCYE agar, biochemical and physiological tests, biofilm assays, serotyping, and molecular methods. One hundred Legionella isolates were recovered. Latex agglutination testing identified 85 isolates as L. pneumophila serogroup 1 and 15 as serogroups 2-15. Antimicrobial susceptibility testing of 93 isolates against nine antibiotics revealed 23 resistant isolates, with selected strains further evaluated by MIC determination. Molecular confirmation using species-specific primers (JFP/JRP, 360 bp) detected 95 positive isolates, including 24 from blood, 17 from urine, and 24 from sputum samples.