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Background: Acinetobacter baumannii is a gram-negative, opportunistic pathogen. Its ability to form biofilm and increasing resistance to antibiotic agents present challenges for infection control. A better understanding of the influence of biofilm formation and antibiotic resistance on environmental persistence of A baumannii in hospital settings is needed for more effective infection control., Methods: A baumannii strains isolated from patients and the hospital environment were identified via Matrix Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF) mass spectrometry (Bruker Daltonics, Bellerica, MA), repetitive extragenic palindromic polymerase chain reaction genotyped, and antibiotic resistance was determined using Vitek 2 (bioMérieux, Inc, Durham NC). Biofilm mass was quantified via microtiter plate method and desiccation tolerance determined up to 56 days., Results: High biofilm forming, clinical, multidrug-resistant- (MDR) positive strains were 50% less likely to die of desiccation than low biofilm, non-MDR strains. In contrast, environmental, MDR-positive, low biofilm forming strains had a 2.7 times increase in risk of cell death due to desiccation compared with their MDR-negative counterparts. MDR-negative, high biofilm forming environmental strains had a 60% decrease in risk compared with their low biofilm forming counterparts., Conclusion: The MDR-positive phenotype was deleterious for environmental strains and the high biofilm phenotype was critical for survival. This study provides evidence of the trade-off between antibiotic resistance and desiccation tolerance, driven by condition-dependent adaptation, and establishes rationale for research into the genetic basis of the variation in fitness cost between clinical and environmental isolates., (Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Acinetobacter baumannii is a significant health care-associated pathogen because it is easily transmitted via fomites, extremely difficult to eradicate from the environment, and highly drug resistant. Understanding the environmentally mediated transmission dynamics of A baumannii is critical for more effective infection control. However, transfer efficiency of pathogen pick-up and deposit remains poorly understood. Our study estimates the transfer efficiency of A baumannii with and without latex glove use from the fingerpad to a fomite and from a fomite to the fingerpad., Methods: Fomite-fingerpad transfer efficiencies were determined for 6 materials (glass, stainless steel, porcelain, polypropylene, polycarbonate, and rubber)., Results: For A baumannii, the fomite-to-fingerpad transfer efficiency was 24.1%, and the fingerpad-to-fomite transfer efficiency was 5.6%. When latex gloves were worn, the fomite-to-fingerpad transfer efficiency was reduced by 55.9% (to 10.6%) and the fingerpad-to-fomite transfer efficiency was reduced by 47.1% (to 3.0%). The average transfer efficiency between 2 skin surfaces was 32.5%., Conclusions: The fomite-to-fingerpad transfer efficiency of A baumannii was statistically significantly higher than the fingerpad-to-fomite transfer efficiency, regardless of glove use. There was no significant difference in transfer efficiency by material type, except for rubber, which resulted in marginally higher transfer efficiencies. Our results underscore the importance of frequently changing gloves during patient care and frequent handwashing-hand hygiene during bare-handed care for the reduction of pathogen transmission., (Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)