Characterization of Bacteria and Inducible Phages in an Intensive Care Unit

Abstract

Intensive care units (ICUs) are critical locations for the transmission of pathogenic and opportunistic microorganisms. Bacteria may develop a synergistic relationship with bacteriophages and more effectively resist various stresses, enabling them to persist despite disinfection and antimicrobial treatment. We collected 77 environmental samples from the surroundings of 12 patients with infection/colonizations by Escherichia coli, Staphylococcus aureus or Klebsiella spp. in an ICU in Austria. Surface swabs were tested for lytic phages and bacterial isolates for mitomycin C-inducible prophages. No lytic bacteriophages were detected, but S. aureus was isolated from the surroundings of all patients. About 85% of the colonies isolated from surface samples were resistant to antimicrobials, with 94% of them multidrug resistant. Two inducible temperate bacteriophages—myovirus vB_EcoM_P5 and siphovirus vB_SauS_P9—were recovered from two clinical isolates. Staphylococci phage vB_SauS_P9 lysed S. aureus isolates from the surface swabs collected from the surroundings of three patients. No transductants were obtained on propagation in phage-sensitive antimicrobial-resistant isolates. The two phages were sensitive to 0.25% (v/v) of the disinfectant TPH Protect, which eliminated viable phages after 15 min. Coliphage vB_EcoM_P5 was inactivated at 70 °C and staphylococci phage vB_SauS_P9 at 60 °C after 60 min.

Antimicrobial Resistance in Escherichia coli and Resistance Genes in Coliphages from a Small Animal Clinic and in a Patient Dog with Chronic Urinary Tract Infection

“…Antibiotic resistance can be spread by a number of mechanisms, and will take place between pets and their owners, or between patients and medical staff [ 13 , 14 ]. Good disinfection regimes with appropriate agents (with virucidal components) will reduce this spread [ 12 ]. Nevertheless, interventions with colonized patients may bear a hazard not to be underestimated.…”

“…One of the issues to be considered is how to avoid the transfer of resistant bacteria and resistance genes using adequate disinfection regimes. Recently, we were able to show that phages are important in resistance transfer; some phages withstand certain disinfectants, and that inadequate disinfection may lead to the possibility of resistance spread by phages [ 11 , 12 ].…”

Nasal decolonization of Staphylococcus aureus and the risk of surgical site infection after surgery: a meta-analysis

“…Staphylococcus aureus (S. aureus), which is normally presented in the microbiota of the human skin and is generally asymptomatic. It remains one of the most common drug-resistant pathogens that causes infection in hospitalized patients [1,2]. Investments in infection reduction have been posed in intensive care units, which has been defined as an "epicenter" of nosocomial infections, by measurements of skin decolonization involving daily chlorhexidine bathing [3].…”

Nasal decolonization of Staphylococcus aureus and the risk of surgical site infection after surgery: a meta-analysis

“…Staphylococcus aureus (S. aureus), which is normally presented in the microbiota of the human skin and is generally asymptomatic. It remains one of the most common drug-resistant pathogens that causes infection in hospitalized patients 1,2 . Investments in infection reduction have been posed in intensive care units, which has been de ned as an "epicenter" of nosocomial infections, by measurements of skin decolonization involving daily chlorhexidine bathing 3 .…”