The Effects of Treating Multispecies Biofilms with Bacteriophage

Biofilms can be found in any environment within proximity to water and are problematic in an assortment of industries. Numerous efforts have been employed to dislodge biofilms including bacteriophages (viruses that infect bacteria). Phage remediation is a promising solution for combatting biofilms that form on catheters in long term use patients. These biofilms often result in catheter-associated urinary tract infections (CAUTIs) and are the most common type of healthcare related infection reported. Additionally, they result in longer hospital stays and increased morbidity. To date, most of the research on the topic focuses on single species biofilms, despite their rarity in nature. Here we assess the efficacy of five phages and a phage cocktail to treat both homogeneous as well as heterogeneous, multispecies biofilms. The effects of phage treatment were assessed looking at both the absorbance and colony counts of the biofilm as well as the planktonic fraction. Two phages, Greedy and phiKZ, had the greatest success in lysing bacterial cells and were thus selected for a phage cocktail treatment regimen. By evaluating the effects on both monoculture and heterogeneous biofilms, phage species can more accurately be assessed for their potential use in treating CAUTIs