DNA evidence of Legionella bacteria is present in 164 cooling towers throughout eight of the nine climate regions in the United States, according to an article on the Becker's Clinical Leadership and Infection Control website.
In a study published in PLOS One, researchers took water samples from 196 cooling towers between July and September 2016 — 84 percent (164) contained DNA evidence of Legionella.
Researchers conducted culture tests on Legionella isolates from 78 of the towers.
The team identified 144 isolates, about half of which of which were Legionella pneumophilia.
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