title: Efficacy of surface disinfectant cleaners against emerging highly resistant gram-negative bacteria.
abstract: BACKGROUND
  Worldwide, the emergence of multidrug-resistant gram-negative bacteria is a clinical problem. Surface disinfectant cleaners (SDCs) that are effective against these bacteria are needed for use in high risk areas around patients and on multi-touch surfaces. We determined the efficacy of several SDCs against clinically relevant bacterial species with and without common types of multidrug resistance.
  
  
  METHODS
  Bacteria species used were ATCC strains; clinical isolates classified as antibiotic-susceptible; and multi-resistant clinical isolates from Klebsiella oxytoca, Klebsiella pneumoniae, and Serratia marcescens (all OXA-48 and KPC-2); Acinetobacter baumannii (OXA-23); Pseudomonas aeruginosa (VIM-1); and Achromobacter xylosoxidans (ATCC strain). Experiments were carried out according to EN 13727:2012 in quadruplicate under dirty conditions. The five evaluated SDCs were based on alcohol and an amphoteric substance (AAS), an oxygen-releaser (OR), surface-active substances (SAS), or surface-active-substances plus aldehydes (SASA; two formulations). Bactericidal concentrations of SDCs were determined at two different contact times. Efficacy was defined as a log10 ≥ 5 reduction in bacterial cell count.
  
  
  RESULTS
  SDCs based on AAS, OR, and SAS were effective against all six species irrespective of the degree of multi-resistance. The SASA formulations were effective against the bacteria irrespective of degree of multi-resistance except for one of the four P. aeruginosa isolates (VIM-1). We found no general correlation between SDC efficacy and degree of antibiotic resistance.
  
  
  CONCLUSIONS
  SDCs were generally effective against gram-negative bacteria with and without multidrug resistance. SDCs are therefore suitable for surface disinfection in the immediate proximity of patients. Single bacterial isolates, however, might have reduced susceptibility to selected biocidal agents.
authors.forename: Mirja
authors.initials: M
authors.lastname: Reichel
authors.forename: Anastasija
authors.initials: A
authors.lastname: Schlicht
authors.forename: Christiane
authors.initials: C
authors.lastname: Ostermeyer
authors.affiliation: Bode Science Center, Bode Chemie GmbH, Melanchthonstr, 27, 22525 Hamburg, Germany. guenter.kampf@bode-chemie.de.
authors.forename: Günter
authors.initials: G
authors.lastname: Kampf
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004202:Disinfectants / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000302:isolation & purification; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D004202:Disinfectants