Sit bath systems: A new source of Legionella infection

Abstract

Sit Bath Systems (SBSs) are the most common hygiene method for patients who are not self-sufficient. Therefore, the water quality of SBSs in the nosocomial environment plays a fundamental role in controlling infections for both patients and health-care workers. A long-term study on Legionella and Pseudomonas aeruginosa (P . aeruginosa ) contamination was performed in SBSs (n = 20) of six Health Care Facilities (HCFs). A total of 254 water samples were analyzed following ISO procedures. The samples were positive for P . aeruginosa (46.85%) and Legionella (53.54%), respectively, both over the directive limits. Legionella isolates were identified as: Legionella pneumophila ( L . pneumophila ) serogroups 1, 3, and 6 and Legionella non- pneumophila species ( L . anisa , L . londiniensis , L . rubrilucens , and L . nagelii ). Moreover, the contamination found was studied with respect to median temperature measured (42 °C), from which two groups (A and B) could be distinguished. P . aeruginosa was found in both groups (100% of SBSs), while a higher percentage of Legionella positive samples was found in group A (75% of SBSs), compared to group B (50% of SBSs), showing how Legionella control could be carried out by using temperatures above 42 °C. An analysis of SBS water pipelines, maintenance, and disinfection treatments indicates SBSs as a new source of infection risk for both patients and health-care workers.

Environmental Monitoring of Legionella in Hospitals in the Campania Region: A 5-Year Study

“…Serogroups 3 and 6 were found in environmental water samples in several studies [ 54 , 80 , 81 , 82 , 83 ]. Particularly, serogroup 3 was isolated in hospitals in Iran [ 84 ], while Pignato et al revealed the prevalence of this serogroup in Italian hospitals, which was sometimes associated with serogroup 6 [ 85 ].…”

Multi-criterion analysis of the effect of physico-chemical microbiological agents on Legionella detection in hotel water distribution systems in Crete

“…However, these pathogens' presence or absence fails to determine the growth of opportunistic pathogens (OPs), which are usually not of Enteric or Fecal origin (Felfoldi et al, 2010;Mapili et al, 2020). It has also been suggested that the presence of certain other opportunistic pathogen species or other Legionella species in biofilms promote Legionella growth through increased resistance to temperature and disinfectants by horizontal gene transfer (Girolamini et al, 2022). This however is still controversial as studies suggest both an association and a lack thereof between the growth of Legionella and other OPs such as P. aeruginosa (Masaka et al, 2021;Atnafu et al, 2022).…”

“…and extracellularly by harvesting carbon and energy sources excreted by other bacteria (Declerck et al, 2009;Stojek and Dutkiewicz, 2011). Biofilms also provide protection from disinfectants and temperature while serving as a substrate for exchange of genetic material and play a pivotal role in the maintenance of Legionella through the water system as parts of them get detached as a result of many factors such as temperature (Whiley et al, 2019;Calero Preciado et al, 2021;Girolamini et al, 2022).…”

“…Other studies have revealed that the age and height of a building are positively correlated with Legionella contamination of the water distribution system, possibly because they make it difficult for proper water temperatures to be maintained throughout the entirety of its extent, especially at higher floors. An age of 20 or more years and a number of floors over 10 are also considered risk factors (Masaka et al, 2021;Atnafu et al, 2022;Girolamini et al, 2022). On the contrary, a newer study failed to exhibit a correlation with Legionella growth with the age of a water distribution system pipes (Wingender and Flemming, 2004).…”