In a study released late last year, the Center for Disease Control and Prevention found that cooling towers (CTs) were found to be a leading source of Legionnaires’ disease outbreak across the United States. These results were obtained by obtaining aliquots from various water samples collected during routine Legionella testing from approximately 196 cooling towers across eight of the nine continental US climate regions in order to control for regional differences. After examining these 196 samples, Legionella spp were found in 78 of the samples, L. pneomophila were isolated in approximately 53 of the samples, and L. pneumophila serogroup 1 (lp1) was found from 40 of the samples. As such, overall 144 unique Legionella isolates were identified across the samples with 53% of these unique Legionella isolates being Legionella pneumophila.
A couple of important caveats are worth noting. First and foremost, the numbers discussed above were particular incidents were Legionella isolates were identified; as such, there may be some overlap between samples, such as one sample having more than one Legionella isolate. If this is the case, then it would imply that there was not, in fact, Legionella isolates found in 144 of the 196 samples but rather a potentially far smaller number. Even so, the particularly frequent presence of Legionella isolates within the samples across the United States should make individuals, particularly commercial and residential building owners cautious.
Indeed these results should not necessarily scare people so much as make individuals more precautious. This means ensuring that a proper water distribution system is in place, particularly in buildings or rooms where water systems may not be frequently used or left unused for long periods at a time. Coupled with regular testing and flushing of pipes, there are numerous ways to ensure that an institution or homeowner is properly prepared and protected from potentially exposing oneself to Legionella bacteria or ultimately contracting Legionnaires’ disease.
Jules Zacher is an attorney in Philadelphia who has tried Legionnaires’ disease cases across the U.S. Please visit LegionnaireLawyer.com again for updates.