Legionella contamination in hospitals of the Campania Region: five years of environmental surveillance results.
[legionellosis]
The purpose of this study was to assess the presence and the distribution of Legionella serotypes in 50 hospital facilities in the Campania Region (Italy) through the sampling of their waters.From January 2008 to December 2012, in compliance with the Italian Monitoring Guidelines for Legionellosis, 4.842 water samples were collected from the end points of hot water distribution networks, air conditioning systems, boilers and cooling towers.1.426 (29.4%) of the 4.842 samples resulted positive for Legionella spp, with a bacterial average of 3.40 log10 cfu/L. The frequency of Legionella isolation in the specimens progressively decreased during the study (43.8% in 2008 vs 22.9% in 2012). Samples from cooling towers (32.7%), showers and taps (31.9%) revealed a more frequent presence of the microorganism, although considerable bacterial concentration variability was found in all examined points. A bacterial average of 3.33 + 0.88 log10 cfu/L was detected in cooling towers, whereas the lowest values (2.89 + 0.92 cfu/L) were found in ACSs. The most frequently isolated species were L. pneumophila 2-14, detected in 60.6% of positive samples. Within serotypes, types 6 (23.8%), 8 (21.9%) and 3 (21.4%) resulted as being the most representative.A significant contamination was found in examined centers. It is therefore advisable to systematically implement currently available surveillance and monitoring strategies through the scrupulous monitoring of systems as well as through the application of validated and effective procedures.
