The R3 ends with "These conditions can promote the development of biofilms and opportunistic pathogens such as Legionella, nontuberculous mycobacteria (NTM), and Pseudomonas species."  In a situation [current, ongoing] where a possibly false positive reportable UAT drives an HAI investigation, it is possible that sampling will not return with evidence of legionella, but other opportunistic premise plumbing pathogens just as capable of causing pneumonias, but below the "reportable" radar.  Should we be mindful of alternative organisms and address such situations, in line with the R3?