AUTHOR=Chavignon Marie , Kolenda Camille , Medina Mathieu , Bonhomme Mélanie , Blazere Leslie , Legendre Tiphaine , Tristan Anne , Laurent Frédéric , Butin Marine 

TITLE=Bacteriophage-based decontamination to control environmental colonization by Staphylococcus capitis in neonatal intensive care units: An in vitro proof-of-concept

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.1060825

DOI=10.3389/fcimb.2022.1060825

ISSN=2235-2988

ABSTRACT=<sec><title>Introduction</title><p>In neonatal intensive care units (NICUs), the standard chemical-based disinfection procedures do not allow a complete eradication of pathogens from environmental surfaces. In particular, the clone <italic>Staphylococcus capitis</italic> NRCS-A, a significant pathogen in neonates, was shown to colonize neonatal incubators. The aim of this study was to evaluate the <italic>in vitro</italic> effect of a bacteriophage cocktail on NRCS-A eradication.</p></sec><sec><title>Methods</title><p>Three bacteriophages were isolated, genetically characterized and assessed for their host range using a collection of representative clinical strains (n=31) belonging to the clone NRCS-A. The efficacy of a cocktail including these three bacteriophages to eradicate the reference strain <italic>S. capitis</italic> NRCS-A CR01 was determined in comparison or in combination with the chemical disinfectant Surfanios Premium on either dry inoculum or biofilm-embedded bacteria. The emergence of bacterial resistance against the bacteriophages alone or in cocktail was evaluated by growth kinetics.</p></sec><sec><title>Results</title><p>The three bacteriophages belonged to two families and genera, namely <italic>Herelleviridae/Kayvirus</italic> for V1SC01 and V1SC04 and <italic>Rountreeviridae/Andhravirus</italic> for V1SC05. They were active against 17, 25 and 16 of the 31 tested strains respectively. Bacteriophage cocktails decreased the bacterial inoculum of both dry spots and biofilms, with a dose dependent effect. The sequential treatment with bacteriophages then Surfanios Premium did not show enhanced efficacy. No bacterial resistance was observed when using the bacteriophage cocktail.</p></sec><sec><title>Discussion</title><p>This study established a proof-of-concept for the use of bacteriophages to fight against <italic>S. capitis</italic> NRCS-A. Further investigations are needed using a larger bacterial collection and in real-life conditions before being able to use such technology in NICUs</p></sec>