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Henny C. Van Der Mei - One of the best experts on this subject based on the ideXlab platform.

  • Transmission of Monospecies and Dual-Species Biofilms From Smooth to Nanopillared Surfaces
    Applied and environmental microbiology, 2018
    Co-Authors: Gusnaniar, Henny C. Van Der Mei, Henk J. Busscher, Titik Nuryastuti, Jelmer Sjollema, Ferdi Hizal, Chang-hwan Choi, Minie Rustema-abbing, René T. Rozenbaum, Stefan W. Wessel
    Abstract:

    ABSTRACT The Transmission of bacteria in biofilms from donor to receiver surfaces precedes the formation of biofilms in many applications. Biofilm Transmission is different from Bacterial adhesion, because it involves biofilm compression in between two surfaces, followed by a separation force leading to the detachment of the biofilm from the donor surface and subsequent adhesion to the receiver surface. Therewith, the Transmission depends on a balance between donor and receiver surface properties and the cohesiveness of the biofilm itself. Here, we compare Bacterial Transmission from biofilms of an extracellular-polymeric-substance (EPS)-producing and a non-EPS-producing staphylococcal strain and a dual-species oral biofilm from smooth silicon (Si) donor surfaces to smooth and nanopillared Si receiver surfaces. Biofilms were fully covering the donor surface before Transmission. However, after Transmission, the biofilms only partly covered the donor and receiver surfaces regardless of nanopillaring, indicating Bacterial Transmission through adhesive failure at the interface between biofilms and donor surfaces as well as through cohesive failure in the biofilms. The numbers of bacteria per unit volume in EPS-producing staphylococcal biofilms before Transmission were 2-fold smaller than in biofilms of the non-EPS-producing strain and of dual species. This difference increased after Transmission in the biofilm left behind on the donor surfaces due to an increased Bacterial density for the non-EPS-producing strain and a dual-species biofilm. This suggests that biofilms of the non-EPS-producing strain and dual species remained compressed after Transmission, while biofilms of the EPS-producing strain were induced to produce more EPS during Transmission and relaxed toward their initial state after Transmission due to the viscoelasticity conferred to the biofilm by its EPS. IMPORTANCE Bacterial Transmission from biofilm-covered surfaces to surfaces is mechanistically different from Bacterial adhesion to surfaces and involves detachment from the donor and adhesion to the receiver surfaces under pressure. Bacterial Transmission occurs, for instance, in food processing or packaging, in household situations, or between surfaces in hospitals. Patients admitted to a hospital room previously occupied by a patient with antibiotic-resistant pathogens are at elevated infection risk by the same pathogens through Transmission. Nanopillared receiver surfaces did not collect less biofilm from a smooth donor than a smooth receiver, likely because the pressure applied during Transmission negated the smaller contact area between bacteria and nanopillared surfaces, generally held responsible for reduced adhesion. Biofilm left behind on smooth donor surfaces of a non-extracellular-polymeric-substance (EPS)-producing strain and dual species had undergone different structural changes than an EPS-producing strain, which is important for their possible further treatment by antimicrobials or disinfectants.

  • Physico-chemistry of Bacterial Transmission versus adhesion.
    Advances in colloid and interface science, 2017
    Co-Authors: Niar Gusnaniar, Henny C. Van Der Mei, Johanna M. M. Hooymans, Titik Nuryastuti, Jelmer Sjollema, Henk J. Busscher
    Abstract:

    Abstract Bacterial adhesion is a main problem in many biomedical, domestic, natural and industrial environments and forms the onset of the formation of a biofilm, in which adhering bacteria grow into a multi-layered film while embedding themselves in a matrix of extracellular polymeric substances. It is usually assumed that Bacterial adhesion occurs from air or by convective-diffusion from a liquid suspension, but often bacteria adhere by Transmission from a Bacterially contaminated donor to a receiver surface. Therewith Bacterial Transmission is mechanistically different from adhesion, as it involves Bacterial detachment from a donor surface followed by adhesion to a receiver one. Transmission is further complicated when the donor surface is not covered with a single layer of adhering bacteria but with a multi-layered biofilm, in which case bacteria can be transmitted either by interfacial failure at the biofilm-donor surface or through cohesive failure in the biofilm. Transmission through cohesive failure in a biofilm is more common than interfacial failure. The aim of this review is to oppose surface thermodynamics and adhesion force analyses, as can both be applied towards Bacterial adhesion, with their appropriate extensions towards Transmission. Opposition of surface thermodynamics and adhesion force analyses, will allow to distinguish between Transmission of bacteria from a donor covered with a (sub)monolayer of adhering bacteria or a multi-layered biofilm. Contact angle measurements required for surface thermodynamic analyses of Transmission are of an entirely different nature than analyses of adhesion forces, usually measured through atomic force microscopy. Nevertheless, Transmission probabilities based on Weibull analyses of adhesion forces between bacteria and donor and receiver surfaces, correspond with the surface thermodynamic preferences of bacteria for either the donor or receiver surface. Surfaces with low adhesion forces such as polymer-brush coated or nanostructured surfaces are thus preferable for use as non-adhesive receiver surfaces, but at the same time should be avoided for use as a donor surface. Since Bacterial Transmission occurs under a contact pressure between two surfaces, followed by their separation under tensile or shear pressure and ultimately detachment, this will affect biofilm structure. During the compression phase of Transmission, biofilms are compacted into a more dense film. After Transmission, and depending on the ability of the Bacterial strain involved to produce extracellular polymeric substances, biofilm left-behind on a donor or transmitted to a receiver surface will relax to its original, pre-Transmission structure owing to the viscoelasticity of the extracellular polymeric substances matrix, when present. Apart from mechanistic differences between Bacterial adhesion and Transmission, the low numbers of bacteria generally transmitted require careful selection of suitably sensitive enumeration methods, for which culturing and optical coherence tomography are suggested. Opposing adhesion and Transmission as done in this review, not only yields a better understanding of Bacterial Transmission, but may stimulate researchers to more carefully consider whether an adhesion or Transmission model is most appropriate in the specific area of application aimed for, rather than routinely relying on adhesion models.

  • Influence of biofilm lubricity on shear-induced Transmission of staphylococcal biofilms from stainless steel to silicone rubber
    Microbial biotechnology, 2017
    Co-Authors: Niar Gusnaniar, Henny C. Van Der Mei, Titik Nuryastuti, Jelmer Sjollema, Ed D. De Jong, Willem Woudstra, Joop De Vries, Henk J. Busscher
    Abstract:

    In real-life situations, bacteria are often transmitted from biofilms growing on donor surfaces to receiver ones. Bacterial Transmission is more complex than adhesion, involving Bacterial detachment from donor and subsequent adhesion to receiver surfaces. Here, we describe a new device to study shear-induced Bacterial Transmission from a (stainless steel) pipe to a (silicone rubber) tube and compare Transmission of EPS-producing and non-EPS-producing staphylococci. Transmission of an entire biofilm from the donor to the receiver tube did not occur, indicative of cohesive failure in the biofilm rather than of adhesive failure at the donor-biofilm interface. Biofilm was gradually transmitted over an increasing length of receiver tube, occurring mostly to the first 50 cm of the receiver tube. Under high-shearing velocity, Transmission of non-EPS-producing bacteria to the second half decreased non-linearly, likely due to rapid thinning of the lowly lubricious biofilm. Oppositely, Transmission of EPS-producing strains to the second tube half was not affected by higher shearing velocity due to the high lubricity and stress relaxation of the EPS-rich biofilms, ensuring continued contact with the receiver. The non-linear decrease of ongoing Bacterial Transmission under high-shearing velocity is new and of relevance in for instance, high-speed food slicers and food packaging.

  • Nonadhesive, silica nanoparticles-based brush-coated contact lens cases-Compromising between ease of cleaning and microbial Transmission to contact lenses
    Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2013
    Co-Authors: Wenwen Qu, Henny C. Van Der Mei, Johanna M. M. Hooymans, Jun Qiu, Nik De-bont, Onko-jan Gelling, Henk J. Busscher
    Abstract:

    Surface properties of lens cases are determinant for their cleanability and for microbial Transmission from lens cases to contact lenses (CLs). PEG-polymer-brush-coatings are known to decrease microbial adhesion more than other surface-coatings. Here, we applied a robust, silica nanoparticles-based brush-coating to polypropylene cases to evaluate their ease of cleaning and probability of Bacterial Transmission to CLs. Adhesion forces of nine Bacterial strains (Pseudomonas, Staphylococci, and Serratia) to rigid CLs, polypropylene, and silica nanoparticles-based brush-coated polypropylene were measured using atomic-force-microscopy and subjected to Weibull analyses to yield Bacterial Transmission probabilities. Biofilms of each strain were grown in coated and uncoated cases and rinsed with a NaCl or antimicrobial lens care solution. Residual, viable organisms were quantified. Bacterial adhesion forces of all strains were significantly, up to tenfold smaller on brush-coated than on uncoated polypropylene. This yielded, higher Transmission probabilities to a CL, but mild-rinsing yielded 10100 fold higher removal of bacteria from brush-coated than from polypropylene cases. Moreover, due to weak adhesion forces, bacteria on brush-coated cases were two-to-three fold more susceptible to an antimicrobial lens care solution than on polypropylene cases. Therewith, the design of lens case surfaces is a compromise between ease of cleaning and Transmission probability to CLs. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013

  • Bacterial adhesion forces to Ag-impregnated contact lens cases and Transmission to contact lenses.
    Cornea, 2013
    Co-Authors: Henk J. Busscher, Henny C. Van Der Mei, Johanna M. M. Hooymans
    Abstract:

    Purpose: To measure adhesion forces of Pseudomonas aeruginosa, Staphylococcus aureus, and Serratia marcescens to a rigid contact lens (CL), standard polypropylene, and Ag-impregnated lens cases using atomic force microscopy and determine Bacterial Transmission from lens case to CL. Methods: Adhesion forces of Bacterial strains to Ag-impregnated and polypropylene lens cases and a rigid CL were measured using atomic force microscopy. Adhesion forces were used to calculate Weibull distributions, from which Transmission probabilities from lens case to CL were derived. Transmission probabilities were compared with actual Transmission of viable bacteria from a lens case to the CL in 0.9% NaCl and in an antimicrobial lens care solution. Results: Bacterial Transmission probabilities from polypropylene lens cases based on force analysis coincided well for all strains with actual Transmission in 0.9% NaCl. Bacterial adhesion forces on Ag-impregnated lens cases were much smaller than that on polypropylene and CLs, yielding a high probability of Transmission. Comparison with actual Bacterial Transmission indicated Bacterial killing due to Ag ions during colony-forming unit Transmission from an Ag-impregnated lens case, especially for P. aeruginosa. Transmission of viable bacteria from Ag-impregnated lens cases could be further decreased by use of an antimicrobial lens care solution instead of 0.9% NaCl. Conclusions: Bacterial Transmission probabilities are higher from Ag-impregnated lens cases than from polypropylene lens cases because of small adhesion forces, but this is compensated for by enhanced Bacterial killing due to Ag impregnation, especially when in combination with an antimicrobial lens care solution. This calls for a balanced combination of antimicrobial lens care solutions and surface properties of a lens case and CL.

Henk J. Busscher - One of the best experts on this subject based on the ideXlab platform.

  • Transmission of Monospecies and Dual-Species Biofilms From Smooth to Nanopillared Surfaces
    Applied and environmental microbiology, 2018
    Co-Authors: Gusnaniar, Henny C. Van Der Mei, Henk J. Busscher, Titik Nuryastuti, Jelmer Sjollema, Ferdi Hizal, Chang-hwan Choi, Minie Rustema-abbing, René T. Rozenbaum, Stefan W. Wessel
    Abstract:

    ABSTRACT The Transmission of bacteria in biofilms from donor to receiver surfaces precedes the formation of biofilms in many applications. Biofilm Transmission is different from Bacterial adhesion, because it involves biofilm compression in between two surfaces, followed by a separation force leading to the detachment of the biofilm from the donor surface and subsequent adhesion to the receiver surface. Therewith, the Transmission depends on a balance between donor and receiver surface properties and the cohesiveness of the biofilm itself. Here, we compare Bacterial Transmission from biofilms of an extracellular-polymeric-substance (EPS)-producing and a non-EPS-producing staphylococcal strain and a dual-species oral biofilm from smooth silicon (Si) donor surfaces to smooth and nanopillared Si receiver surfaces. Biofilms were fully covering the donor surface before Transmission. However, after Transmission, the biofilms only partly covered the donor and receiver surfaces regardless of nanopillaring, indicating Bacterial Transmission through adhesive failure at the interface between biofilms and donor surfaces as well as through cohesive failure in the biofilms. The numbers of bacteria per unit volume in EPS-producing staphylococcal biofilms before Transmission were 2-fold smaller than in biofilms of the non-EPS-producing strain and of dual species. This difference increased after Transmission in the biofilm left behind on the donor surfaces due to an increased Bacterial density for the non-EPS-producing strain and a dual-species biofilm. This suggests that biofilms of the non-EPS-producing strain and dual species remained compressed after Transmission, while biofilms of the EPS-producing strain were induced to produce more EPS during Transmission and relaxed toward their initial state after Transmission due to the viscoelasticity conferred to the biofilm by its EPS. IMPORTANCE Bacterial Transmission from biofilm-covered surfaces to surfaces is mechanistically different from Bacterial adhesion to surfaces and involves detachment from the donor and adhesion to the receiver surfaces under pressure. Bacterial Transmission occurs, for instance, in food processing or packaging, in household situations, or between surfaces in hospitals. Patients admitted to a hospital room previously occupied by a patient with antibiotic-resistant pathogens are at elevated infection risk by the same pathogens through Transmission. Nanopillared receiver surfaces did not collect less biofilm from a smooth donor than a smooth receiver, likely because the pressure applied during Transmission negated the smaller contact area between bacteria and nanopillared surfaces, generally held responsible for reduced adhesion. Biofilm left behind on smooth donor surfaces of a non-extracellular-polymeric-substance (EPS)-producing strain and dual species had undergone different structural changes than an EPS-producing strain, which is important for their possible further treatment by antimicrobials or disinfectants.

  • Physico-chemistry of Bacterial Transmission versus adhesion.
    Advances in colloid and interface science, 2017
    Co-Authors: Niar Gusnaniar, Henny C. Van Der Mei, Johanna M. M. Hooymans, Titik Nuryastuti, Jelmer Sjollema, Henk J. Busscher
    Abstract:

    Abstract Bacterial adhesion is a main problem in many biomedical, domestic, natural and industrial environments and forms the onset of the formation of a biofilm, in which adhering bacteria grow into a multi-layered film while embedding themselves in a matrix of extracellular polymeric substances. It is usually assumed that Bacterial adhesion occurs from air or by convective-diffusion from a liquid suspension, but often bacteria adhere by Transmission from a Bacterially contaminated donor to a receiver surface. Therewith Bacterial Transmission is mechanistically different from adhesion, as it involves Bacterial detachment from a donor surface followed by adhesion to a receiver one. Transmission is further complicated when the donor surface is not covered with a single layer of adhering bacteria but with a multi-layered biofilm, in which case bacteria can be transmitted either by interfacial failure at the biofilm-donor surface or through cohesive failure in the biofilm. Transmission through cohesive failure in a biofilm is more common than interfacial failure. The aim of this review is to oppose surface thermodynamics and adhesion force analyses, as can both be applied towards Bacterial adhesion, with their appropriate extensions towards Transmission. Opposition of surface thermodynamics and adhesion force analyses, will allow to distinguish between Transmission of bacteria from a donor covered with a (sub)monolayer of adhering bacteria or a multi-layered biofilm. Contact angle measurements required for surface thermodynamic analyses of Transmission are of an entirely different nature than analyses of adhesion forces, usually measured through atomic force microscopy. Nevertheless, Transmission probabilities based on Weibull analyses of adhesion forces between bacteria and donor and receiver surfaces, correspond with the surface thermodynamic preferences of bacteria for either the donor or receiver surface. Surfaces with low adhesion forces such as polymer-brush coated or nanostructured surfaces are thus preferable for use as non-adhesive receiver surfaces, but at the same time should be avoided for use as a donor surface. Since Bacterial Transmission occurs under a contact pressure between two surfaces, followed by their separation under tensile or shear pressure and ultimately detachment, this will affect biofilm structure. During the compression phase of Transmission, biofilms are compacted into a more dense film. After Transmission, and depending on the ability of the Bacterial strain involved to produce extracellular polymeric substances, biofilm left-behind on a donor or transmitted to a receiver surface will relax to its original, pre-Transmission structure owing to the viscoelasticity of the extracellular polymeric substances matrix, when present. Apart from mechanistic differences between Bacterial adhesion and Transmission, the low numbers of bacteria generally transmitted require careful selection of suitably sensitive enumeration methods, for which culturing and optical coherence tomography are suggested. Opposing adhesion and Transmission as done in this review, not only yields a better understanding of Bacterial Transmission, but may stimulate researchers to more carefully consider whether an adhesion or Transmission model is most appropriate in the specific area of application aimed for, rather than routinely relying on adhesion models.

  • Influence of biofilm lubricity on shear-induced Transmission of staphylococcal biofilms from stainless steel to silicone rubber
    Microbial biotechnology, 2017
    Co-Authors: Niar Gusnaniar, Henny C. Van Der Mei, Titik Nuryastuti, Jelmer Sjollema, Ed D. De Jong, Willem Woudstra, Joop De Vries, Henk J. Busscher
    Abstract:

    In real-life situations, bacteria are often transmitted from biofilms growing on donor surfaces to receiver ones. Bacterial Transmission is more complex than adhesion, involving Bacterial detachment from donor and subsequent adhesion to receiver surfaces. Here, we describe a new device to study shear-induced Bacterial Transmission from a (stainless steel) pipe to a (silicone rubber) tube and compare Transmission of EPS-producing and non-EPS-producing staphylococci. Transmission of an entire biofilm from the donor to the receiver tube did not occur, indicative of cohesive failure in the biofilm rather than of adhesive failure at the donor-biofilm interface. Biofilm was gradually transmitted over an increasing length of receiver tube, occurring mostly to the first 50 cm of the receiver tube. Under high-shearing velocity, Transmission of non-EPS-producing bacteria to the second half decreased non-linearly, likely due to rapid thinning of the lowly lubricious biofilm. Oppositely, Transmission of EPS-producing strains to the second tube half was not affected by higher shearing velocity due to the high lubricity and stress relaxation of the EPS-rich biofilms, ensuring continued contact with the receiver. The non-linear decrease of ongoing Bacterial Transmission under high-shearing velocity is new and of relevance in for instance, high-speed food slicers and food packaging.

  • Nonadhesive, silica nanoparticles-based brush-coated contact lens cases-Compromising between ease of cleaning and microbial Transmission to contact lenses
    Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2013
    Co-Authors: Wenwen Qu, Henny C. Van Der Mei, Johanna M. M. Hooymans, Jun Qiu, Nik De-bont, Onko-jan Gelling, Henk J. Busscher
    Abstract:

    Surface properties of lens cases are determinant for their cleanability and for microbial Transmission from lens cases to contact lenses (CLs). PEG-polymer-brush-coatings are known to decrease microbial adhesion more than other surface-coatings. Here, we applied a robust, silica nanoparticles-based brush-coating to polypropylene cases to evaluate their ease of cleaning and probability of Bacterial Transmission to CLs. Adhesion forces of nine Bacterial strains (Pseudomonas, Staphylococci, and Serratia) to rigid CLs, polypropylene, and silica nanoparticles-based brush-coated polypropylene were measured using atomic-force-microscopy and subjected to Weibull analyses to yield Bacterial Transmission probabilities. Biofilms of each strain were grown in coated and uncoated cases and rinsed with a NaCl or antimicrobial lens care solution. Residual, viable organisms were quantified. Bacterial adhesion forces of all strains were significantly, up to tenfold smaller on brush-coated than on uncoated polypropylene. This yielded, higher Transmission probabilities to a CL, but mild-rinsing yielded 10100 fold higher removal of bacteria from brush-coated than from polypropylene cases. Moreover, due to weak adhesion forces, bacteria on brush-coated cases were two-to-three fold more susceptible to an antimicrobial lens care solution than on polypropylene cases. Therewith, the design of lens case surfaces is a compromise between ease of cleaning and Transmission probability to CLs. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013

  • Bacterial adhesion forces to Ag-impregnated contact lens cases and Transmission to contact lenses.
    Cornea, 2013
    Co-Authors: Henk J. Busscher, Henny C. Van Der Mei, Johanna M. M. Hooymans
    Abstract:

    Purpose: To measure adhesion forces of Pseudomonas aeruginosa, Staphylococcus aureus, and Serratia marcescens to a rigid contact lens (CL), standard polypropylene, and Ag-impregnated lens cases using atomic force microscopy and determine Bacterial Transmission from lens case to CL. Methods: Adhesion forces of Bacterial strains to Ag-impregnated and polypropylene lens cases and a rigid CL were measured using atomic force microscopy. Adhesion forces were used to calculate Weibull distributions, from which Transmission probabilities from lens case to CL were derived. Transmission probabilities were compared with actual Transmission of viable bacteria from a lens case to the CL in 0.9% NaCl and in an antimicrobial lens care solution. Results: Bacterial Transmission probabilities from polypropylene lens cases based on force analysis coincided well for all strains with actual Transmission in 0.9% NaCl. Bacterial adhesion forces on Ag-impregnated lens cases were much smaller than that on polypropylene and CLs, yielding a high probability of Transmission. Comparison with actual Bacterial Transmission indicated Bacterial killing due to Ag ions during colony-forming unit Transmission from an Ag-impregnated lens case, especially for P. aeruginosa. Transmission of viable bacteria from Ag-impregnated lens cases could be further decreased by use of an antimicrobial lens care solution instead of 0.9% NaCl. Conclusions: Bacterial Transmission probabilities are higher from Ag-impregnated lens cases than from polypropylene lens cases because of small adhesion forces, but this is compensated for by enhanced Bacterial killing due to Ag impregnation, especially when in combination with an antimicrobial lens care solution. This calls for a balanced combination of antimicrobial lens care solutions and surface properties of a lens case and CL.

Randy W Loftus - One of the best experts on this subject based on the ideXlab platform.

  • benefit of systematic selection of pairs of cases matched by surgical specialty for surveillance of Bacterial Transmission in operating rooms
    American Journal of Infection Control, 2020
    Co-Authors: Franklin Dexter, Richard H Epstein, Andrew Gostine, Donald H Penning, Randy W Loftus
    Abstract:

    Background Bacterial Transmission within and between successive surgical cases occurs in operating rooms (ORs), often includes anesthesia equipment as a reservoir, and can be monitored by collecting samples and identifying bacteria by genetic testing. We evaluated how to choose cases for active surveillance to quantify the effectiveness of interventions in 2 groups of ORs (eg, rooms with germicidal lighting vs those without). Methods Data were from a 7 OR single-specialty gastrointestinal endoscopy suite and from a typical 8 OR multispecialty surgical suite. Results At the multispecialty hospital, 40.3% (SE 1.2%) of the total number of cases could be used for surveillance (ie, followed by another case of the same specialty and matched with a corresponding pair of cases from the other OR group). Random selection obtained fewer matched pairs than deliberate selection: mean ratio of random/deliberate = 0.64 (0.01) for the single-specialty and 0.51 (0.02) for the multispecialty suite (P  Conclusions The efficiency of sampling to obtain pairs of successive surgical cases of the same specialty is impaired markedly by randomly selecting pairs of cases (or using convenience sampling) as compared to choosing pairs deliberately. This is important because the number of cases that can be suitably used for surveillance of Bacterial Transmission will typically be less than one-half the total case number.

  • The dynamics and implications of Bacterial Transmission events arising from the anesthesia work area.
    Anesthesia and analgesia, 2015
    Co-Authors: Randy W Loftus, Matthew D Koff, David J. Birnbach
    Abstract:

    Health care-associated infections are a hospital-wide concern associated with a significant increase in patient morbidity, mortality, and health care costs. Bacterial Transmission in the anesthesia work area of the operating room environment is a root cause of 30-day postoperative infections affecting as many as 16% of patients undergoing surgery. A better understanding of anesthesia-related Bacterial Transmission dynamics may help to generate improvements in intraoperative infection control and improve patient safety.

  • video observation to map hand contact and Bacterial Transmission in operating rooms
    American Journal of Infection Control, 2014
    Co-Authors: John Rowlands, Michael L Beach, Mark P Yeager, Hetal M Patel, Bridget C Huysman, Randy W Loftus
    Abstract:

    Background Hand hygiene (HH) is considered a primary intervention to avoid Transmission of bacteria in health care settings and to prevent health care-associated infections. Despite efforts to decrease the incidence of health care-associated infections by improving HH, HH compliance rates vary widely depending on the hospital environment. Methods We used intraoperative video observation to map temporal patterns of anesthesia provider hand contact with anesthesia work environment (AWE) surfaces and to assess HH compliance. Serial Bacterial cultures of high contact objects were subsequently used to characterize Bacterial Transmission over time. Results Using World Health Organization criteria, we found a large number of HH opportunities and a low rate of HH compliance by anesthesia providers (mean, 2.9%). We observed an inverse correlation between provider hand hygiene compliance during induction and emergence from anesthesia (3.2% and 4.1%, respectively) and the magnitude of AWE surface contamination (103 and 147 CFU, respectively) at these time points. We found no correlation between frequency of hand contact with the AWE and Bacterial contamination. Conclusions Compliance with current HH recommendations by anesthesia providers is not feasible. However, there does appear to be a correlation between HH compliance rates and Bacterial contamination of the AWE, an observation that should stimulate further work to design new methods for control of Bacterial Transmission in operating rooms.

  • Multiple reservoirs contribute to intraoperative Bacterial Transmission.
    Anesthesia and analgesia, 2012
    Co-Authors: Randy W Loftus, Jeremiah R Brown, Michael L Beach, Matthew D Koff, Howard L Corwin, Hetal M Patel, Sundara Reddy, Stephen O. Heard, Patrick G. Fernandez, Jens T. Jensen
    Abstract:

    BACKGROUND: Intraoperative stopcock contamination is a frequent event associated with increased patient mortality. In the current study we examined the relative contributions of anesthesia provider hands, the patient, and the patient environment to stopcock contamination. Our secondary aims were to identify risk factors for stopcock contamination and to examine the prior association of stopcock contamination with 30-day postoperative infection and mortality. Additional microbiological analyses were completed to determine the prevalence of Bacterial pathogens within intraoperative Bacterial reservoirs. Pulsed-field gel electrophoresis was used to assess the contribution of reservoir Bacterial pathogens to 30-day postoperative infections. METHODS: In a multicenter study, stopcock Transmission events were observed in 274 operating rooms, with the first and second cases of the day in each operating room studied in series to identify within- and between-case Transmission events. Reservoir Bacterial cultures were obtained and compared with stopcock set isolates to determine the origin of stopcock contamination. Between-case Transmission was defined by the isolation of 1 or more Bacterial isolates from the stopcock set of a subsequent case (case 2) that were identical to reservoir isolates from the preceding case (case 1). Within-case Transmission was defined by the isolation of 1 or more Bacterial isolates from a stopcock set that were identical to Bacterial reservoirs from the same case. Bacterial pathogens within these reservoirs were identified, and their potential contribution to postoperative infections was evaluated. All patients were followed for 30 days postoperatively for the development of infection and all-cause mortality. RESULTS: Stopcock contamination was detected in 23% (126 out of 548) of cases with 14 between-case and 30 within-case Transmission events confirmed. All 3 reservoirs contributed to between-case (64% environment, 14% patient, and 21% provider) and within-case (47% environment, 23% patient, and 30% provider) stopcock Transmission. The environment was a more likely source of stopcock contamination than provider hands (relative risk [RR] 1.91, confidence interval [CI] 1.09 to 3.35, P = 0.029) or patients (RR 2.56, CI 1.34 to 4.89, P = 0.002). Hospital site (odds ratio [OR] 5.09, CI 2.02 to 12.86, P = 0.001) and case 2 (OR 6.82, CI 4.03 to 11.5, P < 0.001) were significant predictors of stopcock contamination. Stopcock contamination was associated with increased mortality (OR 58.5, CI 2.32 to 1477, P = 0.014). Intraoperative Bacterial contamination of patients and provider hands was linked to 30-day postoperative infections. CONCLUSIONS: Bacterial contamination of patients, provider hands, and the environment contributes to stopcock Transmission events, but the surrounding patient environment is the most likely source. Stopcock contamination is associated with increased patient mortality. Patient and provider Bacterial reservoirs contribute to 30-day postoperative infections. Multimodal programs designed to target each of these reservoirs in parallel should be studied intensely as a comprehensive approach to reducing intraoperative Bacterial Transmission.

  • hand contamination of anesthesia providers is an important risk factor for intraoperative Bacterial Transmission
    Anesthesia & Analgesia, 2011
    Co-Authors: Randy W Loftus, Matthew K Muffly, Jeremiah R Brown, Michael L Beach, Matthew D Koff, Howard L Corwin, Stephen D Surgenor, Kathryn B Kirkland, Mark P Yeager
    Abstract:

    BACKGROUND: We have recently shown that intraoperative Bacterial Transmission to patient IV stopcock sets is associated with increased patient mortality. In this study, we hypothesized that Bacterial contamination of anesthesia provider hands before patient contact is a risk factor for direct intraoperative Bacterial Transmission. METHODS: Dartmouth‐Hitchcock Medical Center is a tertiary care and level 1 trauma center with 400 inpatient beds and 28 operating suites. The first and second operative cases in each of 92 operating rooms were randomly selected for analysis. Eighty-two paired samples were analyzed. Ten pairs of cases were excluded because of broken or missing sampling protocol and lost samples. We identified cases of intraoperative Bacterial Transmission to the patient IV stopcock set and the anesthesia environment (adjustable pressure-limiting valve and agent dial) in each operating room pair by using a previously validated protocol. We then used biotype analysis to compare these transmitted organisms to those organisms isolated from the hands of anesthesia providers obtained before the start of each case. Provider-origin Transmission was defined as potential pathogens isolated in the patient stopcock set or environment that had an identical biotype to the same organism isolated from hands of providers. We also assessed the efficacy of the current intraoperative cleaning protocol by evaluating isolated potential pathogens identified at the start of case 2. Poor intraoperative cleaning was defined as 1 or more potential pathogens found in the anesthesia environment at the start of case 2 that were not there at the beginning of case 1. We collected clinical and epidemiological data on all the cases to identify risk factors for contamination. RESULTS: One hundred sixty-four cases (82 case pairs) were studied. We identified intraoperative Bacterial Transmission to the IV stopcock set in 11.5% (19/164) of cases, 47% (9/19) of which were of provider origin. We identified intraoperative Bacterial Transmission to the anesthesia environment in 89% (146/164) of cases, 12% (17/146) of which were of provider origin. The number of rooms that an attending anesthesiologist supervised simultaneously, the age of the patient, and patient discharge from the operating room to an intensive care unit were independent predictors of Bacterial Transmission events not directly linked to providers. CONCLUSION: The contaminated hands of anesthesia providers serve as a significant source of patient environmental and stopcock set contamination in the operating room. Additional sources of intraoperative Bacterial Transmission, including postoperative environmental cleaning practices, should be further studied. (Anesth Analg 2011;112:98‐105)

Johanna M. M. Hooymans - One of the best experts on this subject based on the ideXlab platform.

  • Physico-chemistry of Bacterial Transmission versus adhesion.
    Advances in colloid and interface science, 2017
    Co-Authors: Niar Gusnaniar, Henny C. Van Der Mei, Johanna M. M. Hooymans, Titik Nuryastuti, Jelmer Sjollema, Henk J. Busscher
    Abstract:

    Abstract Bacterial adhesion is a main problem in many biomedical, domestic, natural and industrial environments and forms the onset of the formation of a biofilm, in which adhering bacteria grow into a multi-layered film while embedding themselves in a matrix of extracellular polymeric substances. It is usually assumed that Bacterial adhesion occurs from air or by convective-diffusion from a liquid suspension, but often bacteria adhere by Transmission from a Bacterially contaminated donor to a receiver surface. Therewith Bacterial Transmission is mechanistically different from adhesion, as it involves Bacterial detachment from a donor surface followed by adhesion to a receiver one. Transmission is further complicated when the donor surface is not covered with a single layer of adhering bacteria but with a multi-layered biofilm, in which case bacteria can be transmitted either by interfacial failure at the biofilm-donor surface or through cohesive failure in the biofilm. Transmission through cohesive failure in a biofilm is more common than interfacial failure. The aim of this review is to oppose surface thermodynamics and adhesion force analyses, as can both be applied towards Bacterial adhesion, with their appropriate extensions towards Transmission. Opposition of surface thermodynamics and adhesion force analyses, will allow to distinguish between Transmission of bacteria from a donor covered with a (sub)monolayer of adhering bacteria or a multi-layered biofilm. Contact angle measurements required for surface thermodynamic analyses of Transmission are of an entirely different nature than analyses of adhesion forces, usually measured through atomic force microscopy. Nevertheless, Transmission probabilities based on Weibull analyses of adhesion forces between bacteria and donor and receiver surfaces, correspond with the surface thermodynamic preferences of bacteria for either the donor or receiver surface. Surfaces with low adhesion forces such as polymer-brush coated or nanostructured surfaces are thus preferable for use as non-adhesive receiver surfaces, but at the same time should be avoided for use as a donor surface. Since Bacterial Transmission occurs under a contact pressure between two surfaces, followed by their separation under tensile or shear pressure and ultimately detachment, this will affect biofilm structure. During the compression phase of Transmission, biofilms are compacted into a more dense film. After Transmission, and depending on the ability of the Bacterial strain involved to produce extracellular polymeric substances, biofilm left-behind on a donor or transmitted to a receiver surface will relax to its original, pre-Transmission structure owing to the viscoelasticity of the extracellular polymeric substances matrix, when present. Apart from mechanistic differences between Bacterial adhesion and Transmission, the low numbers of bacteria generally transmitted require careful selection of suitably sensitive enumeration methods, for which culturing and optical coherence tomography are suggested. Opposing adhesion and Transmission as done in this review, not only yields a better understanding of Bacterial Transmission, but may stimulate researchers to more carefully consider whether an adhesion or Transmission model is most appropriate in the specific area of application aimed for, rather than routinely relying on adhesion models.

  • Nonadhesive, silica nanoparticles-based brush-coated contact lens cases-Compromising between ease of cleaning and microbial Transmission to contact lenses
    Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2013
    Co-Authors: Wenwen Qu, Henny C. Van Der Mei, Johanna M. M. Hooymans, Jun Qiu, Nik De-bont, Onko-jan Gelling, Henk J. Busscher
    Abstract:

    Surface properties of lens cases are determinant for their cleanability and for microbial Transmission from lens cases to contact lenses (CLs). PEG-polymer-brush-coatings are known to decrease microbial adhesion more than other surface-coatings. Here, we applied a robust, silica nanoparticles-based brush-coating to polypropylene cases to evaluate their ease of cleaning and probability of Bacterial Transmission to CLs. Adhesion forces of nine Bacterial strains (Pseudomonas, Staphylococci, and Serratia) to rigid CLs, polypropylene, and silica nanoparticles-based brush-coated polypropylene were measured using atomic-force-microscopy and subjected to Weibull analyses to yield Bacterial Transmission probabilities. Biofilms of each strain were grown in coated and uncoated cases and rinsed with a NaCl or antimicrobial lens care solution. Residual, viable organisms were quantified. Bacterial adhesion forces of all strains were significantly, up to tenfold smaller on brush-coated than on uncoated polypropylene. This yielded, higher Transmission probabilities to a CL, but mild-rinsing yielded 10100 fold higher removal of bacteria from brush-coated than from polypropylene cases. Moreover, due to weak adhesion forces, bacteria on brush-coated cases were two-to-three fold more susceptible to an antimicrobial lens care solution than on polypropylene cases. Therewith, the design of lens case surfaces is a compromise between ease of cleaning and Transmission probability to CLs. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013

  • Bacterial adhesion forces to Ag-impregnated contact lens cases and Transmission to contact lenses.
    Cornea, 2013
    Co-Authors: Henk J. Busscher, Henny C. Van Der Mei, Johanna M. M. Hooymans
    Abstract:

    Purpose: To measure adhesion forces of Pseudomonas aeruginosa, Staphylococcus aureus, and Serratia marcescens to a rigid contact lens (CL), standard polypropylene, and Ag-impregnated lens cases using atomic force microscopy and determine Bacterial Transmission from lens case to CL. Methods: Adhesion forces of Bacterial strains to Ag-impregnated and polypropylene lens cases and a rigid CL were measured using atomic force microscopy. Adhesion forces were used to calculate Weibull distributions, from which Transmission probabilities from lens case to CL were derived. Transmission probabilities were compared with actual Transmission of viable bacteria from a lens case to the CL in 0.9% NaCl and in an antimicrobial lens care solution. Results: Bacterial Transmission probabilities from polypropylene lens cases based on force analysis coincided well for all strains with actual Transmission in 0.9% NaCl. Bacterial adhesion forces on Ag-impregnated lens cases were much smaller than that on polypropylene and CLs, yielding a high probability of Transmission. Comparison with actual Bacterial Transmission indicated Bacterial killing due to Ag ions during colony-forming unit Transmission from an Ag-impregnated lens case, especially for P. aeruginosa. Transmission of viable bacteria from Ag-impregnated lens cases could be further decreased by use of an antimicrobial lens care solution instead of 0.9% NaCl. Conclusions: Bacterial Transmission probabilities are higher from Ag-impregnated lens cases than from polypropylene lens cases because of small adhesion forces, but this is compensated for by enhanced Bacterial killing due to Ag impregnation, especially when in combination with an antimicrobial lens care solution. This calls for a balanced combination of antimicrobial lens care solutions and surface properties of a lens case and CL.

  • Force analysis of Bacterial Transmission from contact lens cases to corneas, with the contact lens as the intermediary.
    Investigative ophthalmology & visual science, 2011
    Co-Authors: Johanna M. M. Hooymans, Jacob De Vries, Henderina Van Der Mei, Hendrik Busscher
    Abstract:

    PURPOSE. To determine the probability of Transmission of a Staphylococcus aureus strain from a contact lens case, to the contact lens (CL) surfaces, to the cornea, on the basis of Bacterial adhesion forces measured by using atomic force microscopy (AFM). METHODS. Adhesion forces between S. aureus strain 835 probes with rigid and soft CLs, storage cases, and porcine corneas were measured with AFM and used to calculate Weibull distributions, from which the Transmission probability from one surface to another was derived. Bacterial Transmission probabilities from force analyses were compared with experimentally obtained Transmission data. RESULTS. After bond-strengthening, S. aureus adhered to the surface of a lens case with a median force of 10.8 nN. Adhesion forces were different on the soft and rigid CLs (7.7 and 13.6 nN, respectively). Adhesion forces on porcine corneas amounted to 11.8 nN. Data variations were used to calculate the Weibull distribution, from which the probability of Transmission from the lens case to a CL and from the CL to the cornea can be directly read. Final Transmission probabilities from lens case to the cornea were slightly higher for the rigid (24%) than for the soft (19%) CL. Bacterial Transmission determined experimentally increased with increasing contact times, but were within the range of the probabilities derived from Weibull analyses. CONCLUSIONS. Probabilities of Bacterial Transmission from contaminated lens cases to corneas can be derived from Weibull analyses of measured forces of adhesion to the surfaces involved. (Invest Ophthalmol Vis Sci. 2011;52:2565-2570) DOI:10.1167/iovs.10-6392

  • Surface thermodynamics and adhesion forces governing Bacterial Transmission in contact lens related microbial keratitis.
    Journal of colloid and interface science, 2011
    Co-Authors: Henk J. Busscher, Johanna M. M. Hooymans, Henny C. Van Der Mei
    Abstract:

    Contact lens induced microbial keratitis results from Bacterial Transmission from one surface to another. We investigated the adhesion forces of Pseudomonas aeruginosa, Staphylococci and Serratia to different contact lenses, lens cases and corneal surfaces using AFM, and applied a Weibull analysis on these adhesion forces to calculate Bacterial Transmission probabilities from lens case to corneas with a contact lens as an intermediate. Also a new surface thermodynamic parameter was introduced, the interfacial free energy of Transmission, which in essence compares the interfacial free energies of Bacterial adhesion, calculated from measured contact angles with liquids on the donating and receiving surfaces in the Transmission process. Bacterial adhesion forces were generally strongest among all eight strains for the lens case (-6.5 to 12.0 nN) and corneas (-3.5 to -11.5 nN), while contact lenses (-0.6 to -13.1 nN) exerted slightly smaller adhesion forces. Consequently, Bacterial Transmission from lens case to contact lens yielded a smaller contribution in the final Transmission than from contact lens to cornea. Bacterial Transmission probabilities as derived from force analyses were higher when the interfacial free energies of Transmission were more negative, which is in line with surface thermodynamic principles. Therewith this parameter could provide useful in analyzing other Bacterial Transmission phenomena between donating and receiving surfaces as well. (C) 2011 Elsevier Inc. All rights reserved.

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  • Bacterial Transmission from lens storage cases to contact lenses-Effects of lens care solutions and silver impregnation of cases.
    Journal of biomedical materials research. Part B Applied biomaterials, 2008
    Co-Authors: Pit B. J. Vermeltfoort, Henk J. Busscher, Johanna M. M. Hooymans, Henny C. Van Der Mei
    Abstract:

    The killing efficacies of multipurpose lens care solutions on planktonic and biofilm bacteria grown in polypropylene contact lens storage cases with and without silver impregnation and effects on Bacterial Transmission from storage cases to silicone hydrogel contact lenses were investigated. For Transmission studies, biofilms of Staphylococcus aureus 835 or Pseudomonas aeruginosa no. 3 were grown on lens storage cases and incubated with a contact lens in different multipurpose lens care solutions (Opti-Free(R)Express(R), ReNu(R) MultiPlus(R), and SoloCare Aquatrade mark) or 0.9% NaCl. In addition, planktonic bacteria were directly suspended in multipurpose solutions and their killing efficacies were determined. The numbers of transmitted live and dead bacteria on the lenses were measured using a combination of plate counting and fluorescence microscopy. The highest killing efficacies were shown by Opti-Free(R) Express(R) for planktonic as well as for biofilm bacteria. Silver impregnation of lens cases in combination with the prescribed solution increased the killing efficacy for P. aeruginosa in biofilms, whereas effects for S. aureus were minor. Lowest numbers of live and dead bacteria were transmitted to a lens in Opti-Free(R) Express(R) multipurpose solution, with no significant differences between lens types and no effects of silver impregnation. (c) 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008.

  • Bacterial Transmission from lens storage cases to contact lenses-Effects of lens care solutions and silver impregnation of cases
    Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2008
    Co-Authors: Pit B. J. Vermeltfoort, Henk J. Busscher, Johanna M. M. Hooymans, Henny C. Van Der Mei
    Abstract:

    The killing efficacies of multipurpose lens care solutions on planktonic and biofilm bacteria grown in polypropylene contact lens storage cases with and without silver impregnation and effects on Bacterial Transmission from storage cases to silicone hydrogel contact lenses were investigated. For Transmission studies, biofilms of Staphylococcus aureus 835 or Pseudomonas aeruginosa no. 3 were grown on lens storage cases and incubated with a contact lens in different multipurpose lens care solutions (Opti-Free (R) Express (R), ReNu (R) Multiplus (R), and SoloCare Aqua (TM)) or 0.9% NaCl. In addition, planktonic bacteria were directly suspended in multipurpose solutions and their killing efficacies were determined. The numbers of transmitted live and dead bacteria on the lenses were measured using a combination of plate counting and fluorescence microscopy. The highest killing efficacies were shown by Opti-Free (R) Express (R) for planktonic as well as for biofilm bacteria. Silver impregnation of lens cases in combination with the prescribed solution increased the killing efficacy for P. aeruginosa in biofilms, whereas effects for S. aureus were minor. Lowest numbers of live and dead bacteria were transmitted to a lens in Opti-Free (R) Express (R) multipurpose solution, with no significant differences between lens types and no effects of silver impregnation. (C) 2008 Wiley Periodicals, Inc

  • Bacterial Transmission from contact lenses to porcine corneas: an ex vivo study.
    Investigative ophthalmology & visual science, 2005
    Co-Authors: Pit B. J. Vermeltfoort, G. M. Bruinsma, Theo G. Van Kooten, Anneke M. M. Hooymans, Henny C. Van Der Mei, Henk J. Busscher
    Abstract:

    PURPOSE. To quantify the Transmission to ex vivo porcine eyes of Staphylococcus aureus 835 and Pseudomonas aeruginosa 3 from three types of contact lenses - one daily wear and two extended wear - differing in hydrophobicity and roughness. METHODS. One daily wear lens (etafilcon) and two extended-wear lenses (one lotrafilcon A and one balafilcon A) were inoculated in a Bacterial suspension for 30 minutes and then placed on ex vivo porcine eyes. After 16 hours of contact between lens and eye, confocal laser scanning microscopy was used to determine the number of bacteria on the lens and cornea for the calculation of Transmission percentages. RESULTS. Transmission percentages were significantly different for both Bacterial strains from an etafilcon A lens and balafilcon A lens (P = 0.006 and 0.04, respectively). Percentages varied from 51% to 68% for the hydrophobic P. aeruginosa and from 54% to 82% for the hydrophilic S. aureus strain, depending on the contact lens involved. Both strains were transferred the least from the most hydrophilic and roughest lens made of lotrafilcon A, although the difference was only statistically significant for S. aureus. CONCLUSIONS. Bacterial Transmission to the porcine cornea differed in the various types of contact lenses and was least in the hydrophilic and rough lens type.