Persistence of <i>L. pneumophila</i> in monospecies biofilms formed by <i>K. pneumoniae, Flavobacterium sp., P. aeruginosa</i>, or <i>P. fluorescens</i>.

<p>A base biofilm of either <i>K. pneumoniae</i> strain DMDS 92-08-28a (□) (A), <i>Flavobacterium</i> sp. strain CDC-65 (Δ) (B), <i>P. aeruginosa</i> ATCC strain 7700 (◊) (C), or <i>P. fluorescens</i> ATCC strain 17569 (Δ) (D) pre-formed on stainless steel coupons was exposed to <i>L. pneumophila</i> strain 130b (▪) on day 3 and flow of 1∶100 R2A began at 1–2 ml/min. Each data point represents the averages and standard deviations of CFU obtained from the coupons within a single rod. The experiments shown are representative of four experiments for (A) and at least two for (B–D). In a repeat of the experiment using <i>P. aeruginosa</i> base biofilms, no legionellae were recovered at the initial sampling point.</p>