Adenosine Triphosphate Bioluminescence Research Articles

Checking the Cleanliness of Surgical Instruments Using the Adenosine Triphosphate-Bioluminescence Assay

Purpose: Cleaning is crucial for reprocessing reusable surgical instruments (RSIs). In this study, we used the adenosine triphosphate (ATP) bioluminescence method to assess the cleanliness of RSIs according to the cleaning method used.Methods: From April 3 to June 2, 2023, surgical sets, including hemostatic forceps, needle holders, operating scissors, dressing forceps, and suction tubes, that arrived at the decontamination room in the central sterile supply department of one general hospital were selected through convenience sampling. For each of the three cleaning processes, 30 cleaned RSIs were sampled with test swabs for inspection, and the relative light unit value was measured using ATP test equipment.Results: Suction tubes, hemostatic forceps, and needle holders ranked low in cleanliness (<i>x</i><sup>2</sup>=11.69, <i>p</i>=.020), and the contamination rate after mechanical cleaning was significantly lower than that after manual cleaning (<i>x</i><sup>2</sup>=31.34, <i>p</i><.001).Conclusion: Surgical instruments treated by manual processing and those containing tubes were associated with the low cleanliness. Therefore, it is necessary to check whether surgical instruments, including tubes, are manually washed at an appropriate level, and regular monitoring will be required.

Outbreak investigation of Serratia marcescens bloodstream infection in an obstetric ward for high-risk pregnant women

BackgroundSerratia marcescens is a gram-negative bacterium that is widespread in the environment. S. marcescens bacteremia can be fatal during pregnancy and cause persistent chorioamnionitis. This study reports an outbreak of Serratia marcescens bloodstream infection (BSI) among high-risk pregnant women in an obstetric ward. The purpose of this study is to report our experience with the usefulness of the ATP test in hospital environmental management and to confirm that bloodstream infections of patients with the same strain were correlated by WGS testing.MethodsThis retrospective study collected the data of inpatients with S. marcescens bacteremia in obstetric ward for high-risk pregnant women from August 22, 2021, to October 14, 2021. We performed: an adenosine triphosphate (ATP) bioluminescence test in the environment with a high-contact area; environmental culture; on-site monitoring and staff education; and whole-genome sequencing (WGS) to evaluate genetic relationships among S. marcescens isolates.ResultsS. marcescens BSI occurred in four consecutive patients. None of the patients had central venous catheters. An ATP bioluminescence test revealed that high-contact areas and areas for injection preparation were not clean (≥ 1000 relative light units). However, S. marcescens was not identified in the environmental cultures, likely due to intensive environmental cleaning and discarding of potentially contaminated specimens before the culture test. On-site monitoring and education were conducted for 1 month. There were no further reports of BSI until 6 months after the last patient was discharged. WGS performed on three isolates from three patients indicated that the isolated S. marcescens was likely from the same strain.ConclusionsWe controlled an S. marcescens outbreak by improving environmental cleaning as well as education of and behavior changes in healthcare workers. Using the ATP bioluminescence test can provide feedback on environmental cleaning and education. WGS played a role in determining the spread of BSI caused by the same strain.

Can the adenosine triphosphate (ATP) bioluminescence assay be used as an indicator for hospital cleaning? - A pilot study.

In hospital cleaning, there is currently no standard for uniform monitoring of surface cleaning, either in Germany or internationally. One possibility for monitoring is the use of so-called objective methods for checking cleaning performance (e.g. fluorescence or adenosine triphosphate (ATP) method). The aim of the study was to monitor and evaluate the implementation of the adenosine triphosphate (ATP) bioluminescence assay as a cleaning indicator in everyday hospital cleaning, in order to verify its utility and effectiveness. In three phases, five frequently touched surfaces were examined with the ATP bioluminescence assay at different time points. 846 measurements were performed on the dermatology ward of a university hospital (phase 1), 1,350 measurements were performed on five different wards of the university hospital (phase 2), and 1,044 measurements were performed on five wards of another large hospital (phase 3). For this purpose, one structurally old and one structurally new ward as well as an intensive care unit (ICU), an outpatient clinic and a radiology department were selected for phases 2 and 3. With the ATP bioluminescence method, we were able to demonstrate a reduction in values after cleaning: before cleaning mean of ATP, 907 relative light units (RLU) (95% confidence interval [CI] 777; 1,038); after cleaning mean=286 RLU (CI=233; 495) (phase 1) and by intervention (five hours after daily cleaning mean=360 RLU (CI=303; 428); five hours after daily cleaning and two additional cleanings mean=128 RLU (CI=107; 152) (phase 3). The ATP values increased five hours after cleaning in phases 1 and 2, and eight hours after cleaning in phase 3. The structurally old wards had the highest ATP content, the ICU and the radiology department, among others, the lowest. In all phases, door handles showed both a reduction after cleaning or intervention and a subsequent increase in ATP values. Chair armrests, examination tables and door handles had high ATP values overall. The study shows ward differences both for cleaning effects and for the soiling characteristics of surfaces during the course of the day. In addition, it demonstrates the benefit of intermediate cleaning twice a day. It is noteworthy that structurally old stations and older inventory were more heavily soiled and, in some cases, more difficult to clean. The results show that the ATP bioluminescence method is suitable for detecting cleaning effects and can be used in everyday clinical practice for simple cleaning monitoring. Furthermore, it enables the detection of risk surfaces and easy-to-clean surfaces with significant re-soiling.

Evaluation of ATP bioluminescence for rapid determination of cleanliness of livestock trailers after a commercial wash.

Pathogens such as porcine epidemic diarrhea virus (PEDV), porcine reproductive and respiratory syndrome (PRRSV), and E. coli are known to spread by contaminated vehicles and equipment. Pork producers have adopted trailer wash policies where each trailer is washed, disinfected, and dried before it can return to a farm. Cleanliness of livestock trailers after washing is determined by visual inspection rather than any objective method. Adenosine triphosphate (ATP) bioluminescence is used in many industries to provide real-time feedback on surface cleanliness through the detection of ATP from organic sources. That same technology may provide trailer wash facilities a way of objectively characterizing a livestock trailer's suitability to return to a farm after washing. Two ATP luminometers (3M Clean-Trace and Neogen AccuPoint) were used to estimate the correlation between ATP bioluminescence readings and aerobic bacterial plate counts (APCs) from sampled surfaces and to determine locations within a livestock trailer that can accurately estimate surface cleanliness. Five locations in livestock trailers were evaluated. Those locations included the nose access door (NAD), back door flush gate, rear side access door (RSAD), belly flush gate (BFG), and belly side access door (BSAD). There was a positive log-log association between the two luminometers (r = 0.59, P < 0.01). Every log unit increase in one unit, resulted in a 0.42 log increase (P < 0.01) in the other unit. ATP can come from bacteria, yeasts, molds, and manure. There was a poor association (r ≥ 0.10, P ≥ 0.02) between APCs and the ATP luminometers. Still, an increase in relative light units (RLUs) resulted in a corresponding increase in colony-forming units. The greatest area of surface contamination measured by APC was the NAD. RLUs were also greater in the NAD compared to the RSAD, the BFG, and the BSAD (P ≤ 0.01). Because APCs and luminometer RLUs provided similar outcomes, statistical process control charts were developed to determine control limits for RLUs. This provides real-time feedback to trailer wash workers in determining cleanliness outcomes for livestock trailers. These data suggest that ATP bioluminescence can be a reliable method to monitor cleaning effectiveness in livestock trailers. Bioluminescence is a monitoring tool that should be used in conjunction with microbial methods to monitor procedures for cleaning and disinfection.

Assessment of Soiling on Highly Touched Clinical Surfaces in Intensive Care Units.

The aim of this study is to evaluate highly touched clinical surfaces using visual inspection methods and adenosine triphosphate by bioluminescence to identify soiling in intensive care units. Descriptive, cross-sectional study carried out in three intensive care units located in Belo Horizonte, MG, Brazil. Data collection included 142 assessments of environmental surfaces. For data analysis, the Pareto diagram and descriptive statistics were used through measures of central tendency. The visual inspection identified dirtiness in the infusion pump, alcohol dispenser, and telephone. The surface that showed a high level of contamination by organic matter identified by the adenosine triphosphate bioluminescence test was the telephone, with a median of 1012 RLU/cm2 (±348.8). The surface evaluation methods used in the intensive care units made it possible to identify dirt on surfaces highly touched by hands, reinforcing the need for investments in training and audits in the process of cleaning and disinfecting surfaces.

The effectiveness of disinfection protocols in osteopathic family medicine offices.

Healthcare-associated infections (HAIs) pose a substantial public health threat. Despite significant strides tocurb HAIs in hospital environments, outpatient settings have not received the same degree of attention. Given their emphasis on holistic, patient-centered care, osteopathic family medicine offices are pivotal in both disease prevention and comprehensive patient treatment. The importance of simple yet effective disinfection protocols, such as thorough cleaning between patient appointments, cannot be overstated in these settings because they are integral to minimizing disease transmission. This study aims to assess the effectiveness of the current disinfection protocols in osteopathic family medicine offices. A cross-sectional study evaluating disinfection practices on 18 examination tables in an osteopathic family medicine office was conducted. Two high-touch surfaces (midtorso region and table edge) were examined. Initial swab samples were collected after morning disinfection by Environmental Services, and terminal swab samples were gathered after day's-end disinfection by the medical staff. Adenosine triphosphate (ATP) bioluminescence assays were performed utilizing AccuPoint Advanced HC Reader, which quantified ATP, indicating contamination levels in the samples. The higher the ATP levels found in a sample, the greater the amount of biological contamination. All samplers were handled and tested as per manufacturer's instructions. Apreliminary trial was conducted to confirm the internal validity of ATP bioluminescence measurements. The statistical analysis involved Shapiro-Wilk and Wilcoxon signed-rank tests, with significance set at p<0.05. Cohen's d test was utilized to calculate the effect size, identifying meaningful differences in initial and terminal swab sample relative light units (RLUs). The midtorso region demonstrated an 11.1 % increase in failure rate after terminal disinfection when compared to initial disinfection. A Wilcoxon signed-rank testrevealed a median estimated pathogen level forthemidtorso region that was higher after terminal disinfection (median, 193 RLUs; range, 1-690 RLUs; n=18) compared to initial disinfection (median, 134 RLUs; range,4-946 RLUs; n=18). However, this increase was not statistically significant, p=0.9124, with a small effect size, d=0.04. The edge showed no change in failure rate after terminal disinfection, maintaining a 100 % failure rate both before and after disinfection. However, the Wilcoxon signed-rank test revealed a slight reduction in the median estimated pathogen levels after terminal disinfection (median, 2095 RLUs; range, 891-5,540 RLUs; n=18) compared to before disinfection (median, 2,257 RLUs; range, 932-5,825 RLUs; n=18). However, this reduction wasnot statistically significant, p=0.61, with a small effect size, d=0.12. The findings from this study reveal a substantial disparity in outcomes between the two sample locations, midtorso and edge. The midtorso demonstrated arelatively low failure rate in both initial and terminal swab samples, indicating successful outcomes. In contrast, the edge consistently displayed a 100 % failure rate, emphasizing the need for more care and attention when cleaning the edge of the examination to ensure better outcomes. By prioritizing adequate disinfection protocols, including thorough cleaning between patients, osteopathic family medicine offices can more effectively prevent disease transmission and promote patient safety.

A novel strategy for bioaerosol rapid detection based on broad-spectrum high-efficiency magnetic enrichment and separation combined with ATP bioluminescence

Bioaerosol detection technology represented by laser-induced fluorescence (LIF) cannot effectively detect bioaerosols in the presence of interferents such as plant-derived smoke, industrial waste gas, pollen and pollen debris which can produce strong non-biological fluorescence interference. To overcome this drawback, in this study, a novel method based on broad-spectrum high-efficiency magnetic enrichment and separation combined with adenosine triphosphate (ATP) bioluminescence was proposed for Escherichia coli (E. coli) bioaerosols rapid detection. First, E. coli bioaerosols mixed with interferents were collected. Core-shell Fe3O4@Polydopamine@Polyethyleneimine magnetic particles were used as bioaerosol enrichment materials to enrich E. coli bioaerosol sampling solutions. Subsequently, an ATP bioluminescence assay was performed to determine the concentration of E. coli. A linear relationship was observed between ATP bioluminescence intensity after enrichment and the E. coli bioaerosol concentration in the range of 870–49,098 particles per liter; the bioluminescence intensity measured after enrichment was significantly higher than that before enrichment, and this enrichment method provide a 6-fold better sensitivity in bioaerosol detection. More importantly, this method efficiently enriched and detected bioaerosols in plant-derived smoke. This method can effectively improve the sensitivity of ATP bioluminescence detection, and possesses the advantages of convenient operation and strong anti-interference ability. It also provides a foundation for the effective detection of bioaerosols mixed with interfering substances, and a reference for evaluating the sensitivity and anti-interference of LIF-based instruments.

Development of a Novel ATP Bioluminescence Assay Based on Engineered Probiotic Saccharomyces boulardii Expressing Firefly Luciferase.

Quantitative analysis of adenosine triphosphate (ATP) has been widely used as a diagnostic tool in the food and medical industries. Particularly, the pathogenesis of a few diseases including inflammatory bowel disease (IBD) is closely related to high ATP concentrations. A bioluminescent D-luciferin/luciferase system, which includes a luciferase (FLuc) from the firefly Photinus pyralis as a key component, is the most commonly used method for the detection and quantification of ATP. Here, instead of isolating FLuc produced in recombinant Escherichia coli, we aimed to develop a whole-cell biocatalyst system that does not require extraction and purification of FLuc. To this end, the gene coding for FLuc was introduced into the genome of probiotic Saccharomyces boulardii using the CRISPR/Cas9-based genome editing system. The linear relationship (r2 = 0.9561) between ATP levels and bioluminescence generated from the engineered S. boulardii expressing FLuc was observed in vitro. To explore the feasibility of using the engineered S. boulardii expressing FLuc as a whole-cell biosensor to detect inflammation biomarker (i.e., ATP) in the gut, a colitis mouse model was established using dextran sodium sulfate as a colitogenic compound. Our findings demonstrated that the whole-cell biosensor can detect elevated ATP levels during gut inflammation in mice. Therefore, the simple and powerful method developed herein could be applied for non-invasive IBD diagnosis.

Point-of-Care Diagnostic Devices for Detection of Escherichia coli O157:H7 Using Microfluidic Systems: A Focused Review.

Bacterial infections represent a serious and global threat in modern medicine; thus, it is very important to rapidly detect pathogenic bacteria, such as Escherichia coli (E. coli) O157:H7. Once treatments are delayed after the commencement of symptoms, the patient's health quickly deteriorates. Hence, real-time detection and monitoring of infectious agents are highly critical in early diagnosis for correct treatment and safeguarding public health. To detect these pathogenic bacteria, many approaches have been applied by the biosensors community, for example, widely-used polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), culture-based method, and adenosine triphosphate (ATP) bioluminescence. However, these approaches have drawbacks, such as time-consumption, expensive equipment, and being labor-intensive, making it critical to develop ultra-sensitive and highly selective detection. The microfluidic platform based on surface plasmon resonance (SPR), electrochemical sensing, and rolling circle amplification (RCA) offers proper alternatives capable of supplementing the technological gap for pathogen detection. Note that the microfluidic biochip allows to develop rapid, sensitive, portable, and point-of-care (POC) diagnostic tools. This review focuses on recent studies regarding accurate and rapid detection of E. coli O157:H7, with an emphasis on POC methods and devices that complement microfluidic systems. We also examine the efficient whole-body detection by employing antimicrobial peptides (AMPs), which has attracted growing attention in many applications.

Using adenosine triphosphate bioluminescence level monitoring to identify bacterial reservoirs during two consecutive Enterococcus faecium and Staphylococcus capitis nosocomial infection outbreaks at a neonatal intensive care unit

IntroductionThis study aimed to assess the role of adenosine triphosphate (ATP) bioluminescence level monitoring for identifying reservoirs of the outbreak pathogen during two consecutive outbreaks caused by Enterococcus faecium and Staphylococcus capitis at a neonatal intensive care unit (NICU). The secondary aim was to evaluate the long-term sustainability of the infection control measures employed one year after the final intervention measures.MethodsTwo outbreaks occurred during a 53-day period in two disconnected subunits, A and B, that share the same attending physicians. ATP bioluminescence level monitoring, environmental cultures, and hand cultures from healthcare workers (HCW) in the NICU were performed. Pulsed-field gel electrophoresis (PFGE) typing was carried out to investigate the phylogenetic relatedness of the isolated strains.ResultsFour cases of E. faecium sepsis (patients A-8, A-7, A-9, B-8) and three cases of S. capitis sepsis (patients A-16, A-2, B-8) were diagnosed in six preterm infants over a span of 53 days. ATP levels remained high on keyboard 1 of the main station (2076 relative light unit [RLU]/100 cm2) and the keyboard of bed A-9 (4886 RLU/100 cm2). By guidance with the ATP results, environmental cultures showed that E. faecium isolated from the patients and from the main station’s keyboard 1 were genotypically indistinguishable. Two different S. capitis strains caused sepsis in three patients. A total 77.8% (n = 7/9) of S. capitis cultured from HCW's hands were genotypically indistinguishable to the strains isolated from A-2 and A-16. The remaining 22.2% (n = 2/9) were genotypically indistinguishable to patient B-8. Three interventions to decrease the risk of bacterial transmission were applied, with the final intervention including a switch of all keyboards and mice in NICU-A and B to disinfectable ones. Post-intervention prospective monitoring up to one year showed a decrease in blood culture positivity (P = 0.0019) and catheter-related blood stream infection rate (P = 0.016) before and after intervention.ConclusionATP monitoring is an effective tool in identifying difficult to disinfect areas in NICUs. Non-medical devices may serve as reservoirs of pathogens causing nosocomial outbreaks, and HCWs' hands contribute to bacterial transmission in NICUs.

The effectiveness of disinfection protocols in medical school osteopathic manipulative medicine labs.

In light of the COVID-19 pandemic, healthcare-associated infections have taken center stage. Healthcare has adjusted workflows to accommodate for more robust disinfecting regiments to help protect the community. This has resulted in the need for medical institutions to reevaluate the current disinfection protocols down to the student level. The osteopathic manipulative medicine (OMM) laboratory provides an optimal avenue for assessing the effectiveness of medical students' ability to clean examination tables. With OMM laboratories having a high level of interaction, adequate disinfection is important for the health and safety of students and teaching faculties. This study will evaluate the effectiveness of the current disinfection protocols in the medical school OMM labs. A cross-sectional, nonrandomized study was performed on 20 OMM examination tables utilized for osteopathic training. Tableswere chosen based on their close proximity to the podium. Close proximity was utilized as a criteria to increase the probability of utilization by students. The sampled tables were observed to ensure their use by students during class. Initial samples were collected in the morning after disinfection by Environmental Services. Terminal samples were collected after Osteopathic medical students utilized and disinfected the OMM examination tables. Samples were collected from the face-cradle and midtorso regions and analyzed utilizing adenosine triphosphate (ATP) bioluminescence assays with an AccuPoint Advanced HC Reader. This reader provides a digital readout of the quantity of light measured in relative light units (RLUs), which is directly correlated to the amount of ATP present in the sample, providing an estimated pathogen count. For statistical analysis, a Wilcoxon signed-rank test was utilized to find statistical differences in RLUs in samples after initial and terminal disinfection. The face cradle showed a 40 % increase in failure rate in samples after terminal disinfection when samples were compared after initial disinfection. A Wilcoxon signed-rank test revealed an estimated pathogen level for face cradle that was significantly higher after terminal disinfection (median, 4,295 RLUs; range, 2,269-12919 RLUs; n=20) compared to initial disinfection (median, 769 RLUs; range, 29-2,422 RLUs; n=20), z=-3.8, p=0.00008, with a large effect size, d=2.2. The midtorso region showed a 75 % increase in samples after terminal disinfection when samples were compared after initial disinfection. A Wilcoxon signed-rank test revealed that the estimated pathogen levels for midtorso were significantly higher after terminal disinfecting (median, 656 RLUs; range, 112-1,922 RLUs; n=20) compared to initial disinfecting (median, 128 RLUs; range, 1-335 RLUs; n=20), z=-3.9, p=0.00012, with a large effect size, d=1.8. This study suggests that medical students frequently failed to disinfect high-touch regions on examination tables, such as the midtorso and the face cradle. It is recommended that the current OMM lab disinfection protocol be modified to include the disinfection of high-touch regions in order to reduce the possibility of pathogen transmission. Further research should explore the effectiveness of disinfection protocols in clinical settings such as outpatient offices.

Evaluation of cleaning process efficacy of instruments for robotic surgery using the adenosine triphosphate test

BackgroundDespite the advances in robotic surgery and its benefits for the patient and surgeon, there are difficulties and challenges in reprocessing surgical instruments, including with regard to patient safety, such as the risk of infection. The aim of this article is to evaluate the effectiveness of manual plus ultrasonic cleaning of EndoWrist devices used in robotic surgery using the adenosine triphosphate bioluminescence quantitative test. MethodsA prospective cross-sectional study assessed the cleanliness of robotic instrumentals used in surgeries. Surgical instruments were collected immediately after the end of the surgery and sent for cleaning and disinfection following standard hospital procedures. The adenosine triphosphate test was done after visual evaluation. According to our hospital standard, instruments were classified as “approved” if the test found ≤50 relative light units. FindingsWe evaluated 279 EndoWrist instruments from 65 robotic surgeries. The most frequently used instruments were needle drivers (102; 39%), followed by bipolar instruments (65; 25%). Median relative light units were 49 (range = 4–13,095); 54% of instruments were classified as approved according to the hospital’s threshold (relative light units ≤50) and 78% when the manufacturer’s threshold (relative light units ≤150) was used. Monopolar instruments presented the best rate of approval (94% considering relative light units ≤50 and 100% with relative light units ≤150). The average relative light units did not vary with the number of reuses. There were no surgical site infections. ConclusionManual plus automated cleaning processes reduced bioburden in all situations evaluated. It seems that instruments can be safely reprocessed ≤9 times and that monopolar instruments are the easiest to clean.

Size-classified monitoring of ATP bioluminescence for rapid assessment of biological distribution in airborne particulates

The COVID-19 pandemic ignited massive research into the rapid detection of bioaerosols. In particular, nanotechnology-based detection strategies are proposed as alternatives because of issues in bioaerosol enrichment and lead time for molecular diagnostics; however, the practical implementation of such techniques is still unclear due to obstacles regarding the large research and development effort and investment for the validation. The use of adenosine triphosphate (ATP) bioluminescence (expressed as relative luminescence unit (RLU) per unit volume of air) of airborne particulate matter (PM) to determine the bacterial population as a representative of the total bioaerosols (viruses, bacteria, and fungi) has been raised frequently because of the high reponse speed, resolution, and compatibility with culture-based bioaerosol monitoring. On the other hand, additional engineering attempts are required to confer significance because of the size-classified (bioluminescence for different PM sizes) and specific (bioluminescence per unit PM mass) biological risks of air for providing proper interventions in the case of airborne transmission. In this study, disc-type impactors to cut-off aerosols larger than 1 μm, 2.5 μm, and 10 μm were designed and constructed to collect PM1, PM2.5, and PM10 on sampling swabs. This engineering enabled reliable size-classified bioluminescence signals using a commercial ATP luminometer after just 5 min of air intake. The simultaneous operations of a six-stage Andersen impactor and optical PM spectrometers were conducted to determine the correlations between the resulting RLU and colony forming unit (CFU; from the Andersen impactor) or PM mass concentration (deriving specific bioluminescence).

Comparison of coliform paper test and ATP bioluminescence assay for monitoring the disinfection of kitchen utensils in canteens of hebei, China

BackgroundTwo common techniques used in canteen hygiene supervision, are the coliform paper assay, which is the standard method, and the adenosine triphosphate (ATP) bioluminescence method. The coliform paper assay requires the incubation of the sample, which is time-consuming and does not provide a real-time assessment. Meanwhile, the ATP bioluminescence assay can provide real-time kitchenware cleanliness data. ObjectiveThis study aimed to compare these two methods for evaluating the sanitary condition of kitchenware and explore whether the ATP bioluminescence assay can be used as a standard method in sanitary inspection. MethodsIn this study, the cluster random sampling method was used to sample kitchenware from six canteens in the Hebei province, China. Samples were, assessed through the coliform paper test and ATP bioluminescence assay. ResultsKitchenware negative rates for the coliform paper method and the ATP test were 64.39% and 49.07%, respectively. The Escherichia coli positive detection rate grew steadily as the relative light units (RLU) value for the ATP technique increased. The kappa coefficient for the two methods was 0.549, indicating that the two methods yield relatively consistent results. ConclusionAlthough currently not considered a standard method, simply using ATP detection is advantageous for quick on-site detection in catering unit hygiene supervision.

Evaluation of the Effectiveness of Overheated Dry-Saturated Steam Disinfection in the Control of the Dental Chair Contamination by Bioluminescence Analysis: A Pilot In Vitro Study

This study aimed to evaluate, through Adenosine triphosphate (ATP) bioluminescence analysis, the effectiveness of an overheated dry-saturated steam device (Polti Sani System) in decreasing the superficial microbial contamination on dental chairs’ surfaces after 30 s steam disinfection (T1) in comparison to baseline (T0), i.e., at the end of an aerosol-generating procedure (AGDP), and to investigate any differences in the tested surfaces’ contamination at T0 in relation to the surface’s type. Three dental chair surfaces (scialytic lamp, control button panel, spit bowl), sized 10 × 10 cm each, were swabbed and analyzed before and after steam application. The procedure was repeated 20 times for a total of 60 before–after evaluations. Non-parametric tests were used to analyze Relative Light Unit (RLU) values and categorical data on the ATP molecules’ amount detected on the tested surfaces. Statistically significant differences were found for both RLU and categorical data for all surfaces, and each type of surface evaluated at T0 and T1 (p &lt; 0.05). Differences in RLU among the tested surfaces at T0 were not significant. By reducing the microbial contamination on the evaluated surfaces, the overheated dry-saturated steam system was an effective measure for the disinfection of the dental chair’s surfaces after AGDPs, potentially reducing the risk of cross-infections.

SG-APSIC1065: The effectiveness of an ultraviolet-C device for terminal room disinfection in an intensive care unit

Objectives: Medical devices and the hospital environment can be contaminated easily by multidrug-resistant bacteria. The effectiveness of cleaning practices is often suboptimal because environmental cleaning in hospitals is complex and depends on human factors, the physical and chemical characteristics of environment, and the viability of the microorganisms. Ultraviolet-C (UV-C) lamps can be used to reduce the spread of microorganisms. We evaluated the effectiveness of an ultraviolet-C (UV-C) device on terminal room cleaning and disinfection. Methods: The study was conducted at an ICU of a medical center in Taiwan. We performed a 3-stage evaluation for the effectiveness of UV-C radiation, including pre–UV-C radiation, UV-C radiation, and a bleaching procedure. The 3 stages of evaluation were implemented in the ICU rooms from which a patient had been discharged or transferred. We collected the data from adenosine triphosphate (ATP) bioluminescence testing, colonized strains, and their corresponding colony counts by sampling from the environmental surfaces and air. We tested 8 high-touch surfaces, including 2 sides of bed rails, headboards, footboards, bedside tables, monitors, pumping devices, IV stands, and oxygen flow meters. Results: In total, 1,696 environmental surfaces and 72 air samples were analyzed. The levels of ATP bioluminescence and colony counts of isolated bacteria decreased significantly after UV-C radiation and bleaching disinfection for both the environmental and air samples (P &lt; .001). Resistant bacteria (vancomycin-resistant Enterococcus, VRE) were commonly isolated on the hard-to-clean surfaces of monitors, oxygen flow meters, and IV pumps. However, they were also eradicated (P &lt; .001). Conclusions: UV-C can significantly reduce environmental contamination by multidrug-resistant microorganisms. UV-C is an effective device to assist staff in cleaning the hospital environment.

SG-APSIC1045: A quantitative assessment of ATP bioluminescence on dental instruments reprocessed by automated washer-disinfector and ultrasonic machine

Objectives: Dental instruments are contaminated by blood and saliva during dental procedures. To prevent cross infection, all contaminants should be removed from the surfaces of instruments. Inadequate cleaning can hinder disinfection and sterilization process. To compare the cleaning efficacy of an automated washer–disinfector versus an ultrasonic machine on dental instruments, adenosine triphosphate (ATP) measurements were compared. Methods: From National University Polyclinic Bukit Panjang Dental Services, we collected 2 loads of 40 dental instruments previously used in dental treatments: extraction forceps, high-volume suction tips, Coupland elevators, matrix band holders, and ultrasonic scaler tips. At the point of use, gross soil was wiped from instrument surfaces with water. Each instrument was swabbed after cleaning either using a washer–disinfector or an ultrasonic machine. The relative light units (RLU) on the luminometer indicated the amount of ATP contaminants and residue bioburden present on the instruments. Results: The mean RLU values across all instruments in the washer–disinfector group was 2.5 times lower than the mean value of the instruments in the ultrasonic group (35.4 vs 89.9 RLU). This difference was statistically significant for all instrument groups except for the high-volume suction tips. The Mann-Whitney U test indicated that the RLU in the ultrasonic group was higher than the RLU for the washer–disinfector group for extraction forceps (P &lt; .001), ultrasonic scaler tips (P &lt; .023), and matrix bands (P &lt; .006). A t test indicated the same relationship for Coupland elevators (P &lt; .005). Conclusions: The mean RLU values for both cleaning methods were lower than the manufacturer’s benchmark (RLU ≤ 150), suggesting that both methods can achieve effective cleaning. However, cleaning using an automated washer–disinfector is significantly more effective than an ultrasonic machine for nonlumen instruments. The effectiveness of cleaning using ultrasonic machine varied greatly among different types of instruments with different design complexities.

Effectiveness of adenosine triphosphate to monitor manual cleaning and disinfection efficacy of flexible endoscopes in Hong Kong.

Adenosine triphosphate (ATP) bioluminescence assay is widely adopted in the West to allow rapid evaluation of endoscopes for bacteriologic/biologic residue, but this practice is rarely adopted in Asia. In this continuous quality improvement program, we evaluated the utility of ATP in bacteriologic surveillance on endoscope reprocessing. A total of 456 samples (304 ATP samples and 152 culture samples) of 38 flexible endoscopes were assessed after routine clinical use in a private hospital in Hong Kong. Endoscopes were assessed with an ATP system and bacterial cultures at different time points during the reprocessing. After pre-cleaning, the ATP values ranged from 228 to 65 163 relative light units (RLU) through all endoscope types. After manual cleaning, ATP values were decreased to 7-81 RLU (median, 19 RLU) for endoscope surface and 3-671 RLU (median, 12 RLU) for channel rinsate. There was a significant reduction in ATP levels between pre-cleaning and after manual cleaning. One of the 38 (2.6%) endoscopes (a duodenoscope) had an ATP value of 671 RLU from channel rinsate, which exceeded the benchmark for cleanliness of >200 RLU, and was sent back for re-cleaning. All endoscopes cultured no bacteria after high-level disinfection (HLD) by automated endoscope reprocessor (AER) and storage up to 24 h. ATP values were <200 RLU for all endoscopes after HLD and storage. Adenosine triphosphate bioluminescence assay offers a rapid, practical, and cost-effective alternative for detection of endoscope microbial residue as well as a routine monitoring tool for endoscope cleanliness in the clinical setting.

Impact of Plastic-Wrap Properties and Cleaning Intervals on the Disinfection of Elevator Buttons.

Fomite transmission is a possible route by which different pathogens spread within facilities. In hospital settings, elevator buttons are widely observed to be covered with various types of plastic wraps; however, limited information is available concerning the impact of different plastic materials on cleaning. Our study aimed to identify which plastic material is suitable for the coverage of elevator buttons and the optimal intervals for their cleaning. We tested six plastic covers, including polyethylene (PE), polymethylpentene (PMP), polyvinyl chloride (PVD), and polyvinylidene chloride (PVDC) plastic wraps; a thermoplastic polyurethane (TPU) keyboard cover; and a polyethylene terephthalate-ethylene vinyl acetate (PET-EVA) laminating film, which are plastic films. The bioburden on the elevator buttons at different time intervals was measured using an adenosine triphosphate (ATP) bioluminescence assay. Our results show that wraps made of PVDC had superior durability compared with those of PMP, PVC, and PVDC, in addition to the lowest detectable ATP levels among the six tested materials. Regarding different button locations, the highest ATP values were found in door-close buttons followed by door-open, and first-floor buttons after one- and three-hour intervals (p = 0.024 and p < 0.001, respectively). After routine disinfection, the ATP levels of buttons rapidly increased after touching and became more prominent after three hours (p < 0.05). Our results indicate that PVDC plastic wraps have adequate durability and the lowest residual bioburden when applied as covers for elevator buttons. Door-close and -open buttons were the most frequently touched sites, requiring more accurate and precise disinfection; therefore, cleaning intervals of no longer than three hours may be warranted.

Correlation tests between relative light unit and colony forming unit for improving adenosine triphosphate bioluminescence analysis in bacterial consolidation treatments on palaeontological heritage.

In this article bacterial carbonate mineralization treatments are proposed as a novel strategy for decayed fossils and palaeontological heritage conservation; specifically, by means of inoculation of Myxococcus xanthus, a bacterium of proven effectiveness in ornamental stone bioconsolidation. Bioconsolidation treatments can be very effective, stable, nontoxic, environmentally friendly, and chemically compatible with fossil heritage. The method reproduces what nature has been doing for millennia with fossils that have been permineralized by bacterial calcium carbonate precipitation. There is, however, some concern that bacterial inoculation could lead to the growth of undesirable microbiota, which could subsequently damage the fossil substrate. Because of this, the use of bacteria on heritage items must be meticulously monitored and analysis strategies should be carried out to detect bacteria viability during and after treatments. For this purpose, adenosine triphosphate assay is proposed in this article as a fast, affordable, portable, and easy-to-use system for conservators. as ATP assay results are relative and difficult to relate to colony forming unit, this study aims to improve their applicability by examining the correlation between ATP analysis and total viable bacteria count in the specific case of M. xanthus. This research provides reference and correlatable data to obtain an approximate estimation of M. xanthus viable bacterial colonies based on relative light unit data.