Scalable, effective, and rapid decontamination of SARS-CoV-2 contaminated N95 respirators using germicidal ultraviolet C (UVC) irradiation device.

Particulate respirators such as N95s are an essential component of personal protective equipment (PPE) for front-line workers. This study describes a rapid and effective UVC irradiation system that would facilitate the safe re-use of N95 respirators and provides supporting information for deploying UVC for decontamination of SARS-CoV-2 during the COVID-19 pandemic. To assess the inactivation potential of the proposed UVC germicidal device as a function of time by using 3 M 8211-N95 particulate respirators inoculated with SARS-CoV-2. A germicidal UVC device to deliver tailored UVC dose was developed and test coupons (2.5 cm2) of the 3 M-N95 respirator were inoculated with 106 plaque-forming units (PFU) of SARS-CoV-2 and were UV irradiated. Different exposure times were tested (0-164 s) by fixing the distance between the lamp and the test coupon to 15.2 cm while providing an exposure of at least 5.43 mWcm-2. Primary measure of outcome was titration of infectious virus recovered from virus-inoculated respirator test coupons after UVC exposure. Other measures included the method validation of the irradiation protocol, using lentiviruses (biosafety level-2 agent) and establishment of the germicidal UVC exposure protocol. An average of 4.38 × 103 PFU ml-1 (SD 772.68) was recovered from untreated test coupons while 4.44 × 102 PFU ml-1 (SD 203.67), 4.00 × 102 PFU ml-1 (SD 115.47), 1.56 × 102 PFU ml-1 (SD 76.98) and 4.44 × 101 PFU ml-1 (SD 76.98) was recovered in exposures 2, 6, 18 and 54 s per side respectively. The germicidal device output and positioning was monitored and a minimum output of 5.43 mW cm-2 was maintained. Infectious SARS-CoV-2 was not detected by plaque assays (minimal level of detection is 67 PFU ml-1) on N95 respirator test coupons when irradiated for 120 s per side or longer suggesting 3.5 log reduction in 240 s of irradiation, 1.3 J cm-2. A scalable germicidal UVC device to deliver tailored UVC dose for rapid decontamination of SARS-CoV-2 was developed. UVC germicidal irradiation of N95 test coupons inoculated with SARS-CoV-2 for 120 s per side resulted in 3.5 log reduction of virus. These data support the reuse of N95 particle-filtrate apparatus upon irradiation with UVC and supports use of UVC-based decontamination of SARS-CoV-2 during the COVID-19 pandemic.

Decontaminating N95 respirators during the COVID-19 pandemic: simple and practical approaches to increase decontamination capacity, speed, safety and ease of use.

BACKGROUND: The COVID-19 pandemic has caused a severe shortage of personal protective equipment (PPE), especially N95 respirators. Efficient, effective and economically feasible methods for large-scale PPE decontamination are urgently needed. AIMS: (1) to develop protocols for effectively decontaminating PPE using vaporized hydrogen peroxide (VHP); (2) to develop novel approaches that decrease set-up and take-down time while also increasing decontamination capacity; (3) to test decontamination efficiency for N95 respirators heavily contaminated by make-up or moisturizers. METHODS: We converted a decommissioned Biosafety Level 3 laboratory into a facility that could be used to decontaminate N95 respirators. N95 respirators were hung on metal racks, stacked in piles, placed in paper bags or covered with make-up or moisturizer. A VHP® VICTORY™ unit from STERIS was used to inject VHP into the facility. Biological and chemical indicators were used to validate the decontamination process. FINDINGS: N95 respirators individually hung on metal racks were successfully decontaminated using VHP. N95 respirators were also successfully decontaminated when placed in closed paper bags or if stacked in piles of up to six. Stacking reduced the time needed to arrange N95 respirators for decontamination by approximately two-thirds while almost tripling facility capacity. Make-up and moisturizer creams did not interfere with the decontamination process. CONCLUSIONS: Respirator stacking can reduce the hands-on time and increase decontamination capacity. When personalization is needed, respirators can be decontaminated in labelled paper bags. Make up or moisturizers do not appear to interfere with VHP decontamination.

Efficacy of Malignant Hyperthermia Association of the United States-Recommended Methods of Preparation for Malignant Hyperthermia-Susceptible Patients Using Dräger Zeus Anesthesia Workstations and Associated Costs.

BACKGROUND: The objective of this study was to assess the efficacy and cost of Malignant Hyperthermia Association of the United States-recommended methods for preparing Dräger Zeus anesthesia workstations (AWSs) for the malignant hyperthermia-susceptible patient. METHODS: We studied washout profiles of sevoflurane, isoflurane, and desflurane in 3 Zeus AWS following 3 preparation methods. AWS was primed with 1.2 minimum alveolar concentration anesthetic for 2 hours using 2 L/min fresh gas flow, 500 mL tidal volume, and 12/min respiratory rate. Two phases of washout were performed: high flow (10 L/min) until anesthetic concentration was <5 parts per million (ppm) for 20 minutes and then low flow (3 L/min) for 20 minutes to identify the rebound effect. Preparation methods are as follows: method 1 (M1), changing disposables (breathing circuit, soda lime, CO2 line, and water traps); method 2 (M2), M1 plus replacing the breathing system with an autoclaved one; and method 3 (M3), M1 plus mounting 2 activated charcoal filters on respiratory limbs. Primary outcomes are as follows: time to obtain anesthetic concentration <5 ppm in the high-flow phase, peak anesthetic concentrations in the low-flow phase, and for M3 only, peak anesthetic concentration after 70 minutes of low-flow phase, when activated charcoal filters are removed. Secondary outcomes are as follows: cost analysis of time and resources to obtain anesthetic concentration <5 ppm in each method and a vapor-free Zeus AWS. Sensitivity analyses were performed using alternative assumptions regarding the costs and the malignant hyperthermia-susceptible caseload per year. RESULTS: Primary outcomes were as follows: M3 instantaneously decreased anesthetic concentration to <1 ppm with minimal impact of low-flow phase. M1 (median, 88 minutes; 95% confidence interval [CI], 69-112 minutes) was greater than M2 (median, 11 minutes; 95% CI, 9-15 minutes). Means of peak rebound anesthetic concentrations in M1, M2, and M3 were 15, 6, and 1 ppm, respectively (P < .001). Anesthetic concentration increased 33-fold (95% CI, 21-50) after removing charcoal filters (from 0.7 to 20 ppm). The choice of anesthetic agents did not impact the results. Secondary outcomes were as follows: M3 was the lowest cost when the cost of lost operating room (OR) time due to washout was included, and M1 was the lowest cost when it was not included. When the cost of lost OR time due to washout was considered the estimated cost/case of M3 was US $360 (M1, US $2670; M2, US $969; and a "vapor-free" Zeus AWS was US $930). The OR time and equipment costs represent the largest differentiators among the methods. CONCLUSIONS: Institutions in which demand for OR time has exceeded capacity should consider M3, and institutions with surplus OR capacity should consider M1.

Reducing cost and improving operating room efficiency: examination of surgical instrument processing.

BACKGROUND: Operating room efficiency can be compromised because of surgical instrument processing delays. We observed that many instruments in a standardized tray were not routinely used during thyroid and parathyroid surgery at our institution. Our objective was to create a streamlined instrument tray to optimize operative efficiency and cost. MATERIALS AND METHODS: Head and neck surgical instrument trays were evaluated by operating room team leaders. Instruments were identified as either necessary or unnecessary based on use during thyroidectomies and parathyroidectomies. The operating room preparation time, tray weights, number of trays, and number of instruments were recorded for the original and new surgical trays. Cost savings were calculated using estimated reprocessing cost of $0.51 per instrument. RESULTS: Three of 13 head and neck trays were converted to thyroidectomy and parathyroidectomy trays. The starting head and neck surgical set was reduced from two trays with 98 total instruments to one tray with 36 instruments. Tray weight decreased from 27 pounds to 10 pounds. Tray preparation time decreased from 8 min to 3 min. The new tray saved $31.62 ($49.98 to $18.36) per operation in reprocessing costs. Projected annual savings with hospitalwide implementation is over $28,000.00 for instrument processing alone. Unmeasured hospital savings include decreased instrument wear and replacement frequency, quicker operating room setup, and decreased decontamination costs. CONCLUSIONS: Optimizing surgical trays can reduce cost, physical strain, preparation time, decontamination time, and processing times, and streamlining trays is an effective strategy for hospitals to reduce costs and increase operating room efficiency.

Reducing the risk of iatrogenic Creutzfeldt-Jakob disease by improving the cleaning of neurosurgical instruments.

BACKGROUND: In all, there have been 178 variant Creutzfeldt-Jakob disease (vCJD) patients diagnosed in the UK, with an estimated maximum 1:2000 carriage rate based on archived appendix and tonsil tissue, implying that infection may be rare but carriage relatively frequent. Previous workers have identified that maintenance of surgical instruments in a humid atmosphere after use and prior to cleaning assists cleaning efficacy. Recently the Department of Health/Advisory Committee on Dangerous Pathogens UK have recommended a surgical instrument cleanliness threshold post cleaning of <5 µg protein per instrument side. AIM: To quantify cleanliness of neurosurgical instruments and to investigate cost-effective measures for improved cleaning. METHODS: Two instrument protein quantification methods were used: one based on the International Standard (15883 series) using sodium dodecyl sulphate elution and ortho-phthalaldehyde reaction, and a second in-situ protein fluorescence detection system (ProReveal) providing results per instrument side. In-vitro investigation of the efficacy of some commercial and in-house pre-clean wetting agents was undertaken using artificial test soil and stainless steel discs under standard conditions. In-vivo evaluation of best-performing in-vitro agents was undertaken on craniotomy sets. FINDINGS: ProReveal technology demonstrated that 163 out of 187 (87%) neurosurgical instruments had <5 µg residual protein per instrument side. The use of proprietary National Health Service plastic bags and sterile water-soaked wound pads were equivalent in efficacy to commercial pre-cleaning wetting products and significantly less expensive. CONCLUSION: Although we demonstrate low in-situ protein levels on neurosurgical instruments and the beneficial effects of keeping instruments moist, other cleaning critical-control points such as instrument loading patterns should also be monitored.

Swift and Low-Cost Surge in Chemical Threat Response: Is It Possible? The Experience of a French Hospital.

In 2016 France hosted the European football championship. In a context of an increased terrorist threat, Chemical, Bacteriological, Radiological, Nuclear (CBRN) attacks were considered possible. Three days prior to the beginning of the event, the Health Authorities required that a medium sized hospital close to a major potential target, prepare a chemical decontamination centre. Despite a low level of preparedness, little external help, and very few extra resources, an efficient decontamination chain (all premises necessary for the management of contaminated victims: from the entrance gate to the post-decontamination dressing cabins) was set up in 15 days (12 days after the unrealistic deadline). Numerous practical measures allowed three persons in CBRN personal protective equipment (PPE) to manage the whole chain, providing a maximum flow of 24 persons/hour. Volunteers were trained in PPE dressing, undressing and in decontamination procedures. This experience, offers a novel paradigm in managing chemical decontamination, in terms of attitude, and with adaptations to overcome practical constraints. It demonstrates that it is possible to set up a decontamination chain rapidly at very low cost. This provides an attractive option for less advanced countries and in humanitarian contexts. Some additional refinements, enhancements may be considered to further improve results. (Disaster Med Public Health Preparedness. 2018;12:649-656).

Surveillance-guided selective digestive decontamination of carbapenem-resistant Enterobacteriaceae in the intensive care unit: A cost-effectiveness analysis.

BACKGROUND: Clinical findings have shown effectiveness and safety of selective digestive decontamination (SDD) for eradication of carbapenem-resistant Enterobacteriaceae (CRE) in high-risk carriers. We aimed to evaluate the cost-effectiveness of SDD guided by CRE surveillance in the intensive care unit (ICU). METHODS: Outcomes of surveillance-guided SDD (test-guided SDD) and no screening (control) in the ICU were compared by Markov model simulations. Model outcomes were CRE infection and mortality rates, direct costs, and quality-adjusted life year (QALY) loss. Model inputs were estimated from clinical literature. Sensitivity analyses were conducted to examine the robustness of base case results. RESULTS: Test-guided SDD reduced infection (4.8% vs 5.0%) and mortality (1.8% vs 2.1%) rates at a higher cost ($1,102 vs $1,074) than the control group in base case analysis, respectively. Incremental cost per QALY saved (incremental cost-effectiveness ratio [ICER]) by the test-guided SDD group was $557 per QALY. Probabilistic sensitivity analysis showed that test-guided SDD was effective in saving QALYs in 100% of 10,000 Monte Carlo simulations, and cost-saving 59.1% of time. The remaining 40.9% of simulations found SDD to be effective at an additional cost, with ICERs accepted as cost-effective per the willingness-to-pay threshold. CONCLUSIONS: Surveillance-guided SDD appears to be cost-effective in reducing CRE infection and mortality with QALYs saved.

Benefit-Cost Analysis of Radiocesium Decorporation by a Prussian Blue Treatment and Stockpiling.

In the case of an attack by a "dirty bomb" with cesium-137 there is a risk of internal contamination. The excretion of cesium-137 can be enhanced by Prussian Blue (PB), and thus the committed effective dose be reduced. We analyzed the benefit and costs of PB decorporation treatment. We simulated the reduction of the radiological dose by PB treatment after cesium-137 incorporation by inhalation. The saving of life time was quantified using the monetary "value of a statistical life" (VSL). Treatment costs were based on the market price of PB in Germany. Moreover we considered the holding costs of stockpiling. The benefit of PB treatment increases with its duration up to about 90 days. If treatment initiation is delayed, the maximum achievable benefit is decreased. For a VSL of 1.646 million €, the net benefit of a 90-days treatment started 1 day after the incorporation remains positive up to a stockpiling duration of 10 years. If starting PB treatment as late as the 180th day after incorporation, the costs will surpass the benefit. We conclude that a prompt decision making and early treatment initiation greatly impacts on the medical but also economic efficiency of a PB treatment.

Experimental procedures for decontamination and microbiological testing in cardiovascular tissue banks.

IMPACT STATEMENT: Sterility testing is a critical issue in the recovery, processing, and release of tissue allografts. Contaminated allografts are often discarded, increasing costs, and reducing tissue stocks. Given these concerns, it is important to determine the most effective methodology for sterility testing. This work provides an overview of microbiological methods for sampling and culturing donor grafts for cardiovascular tissue banking.

Decontaminating soil organic pollutants with manufactured nanoparticles.

Organic pollutants in soils might threaten the environmental and human health. Manufactured nanoparticles are capable to reduce this risk efficiently due to their relatively large capacity of sorption and degradation of organic pollutants. Stability, mobility, and reactivity of nanoparticles are prerequisites for their efficacy in soil remediation. On the basis of a brief introduction of these issues, this review provides a comprehensive summary of the application and effectiveness of various types of manufactured nanoparticles for removing organic pollutants from soil. The main categories of nanoparticles include iron (oxides), titanium dioxide, carbonaceous, palladium, and amphiphilic polymeric nanoparticles. Their advantages (e.g., unique properties and high sorption capacity) and disadvantages (e.g., high cost and low recovery) for soil remediation are discussed with respect to the characteristics of organic pollutants. The factors that influence the decontamination effects, such as properties, surfactants, solution chemistry, and soil organic matter, are addressed.

Assessing cost and effectiveness of radiation decontamination in Fukushima Prefecture, Japan.

Despite the enormous cost of radiation decontamination in Fukushima Prefecture, it is not clear what levels of reduction in external radiation exposure are possible in the Special Decontamination Area, the Intensive Contamination Survey Areas and the whole of Fukushima. The objective of this study was to evaluate the cost and effectiveness of radiation decontamination in Fukushima Prefecture in its entirety. Using a geographic information system, we calculated the costs of removal, storage containers, transport, and temporary and interim storage facilities as well as the reduction in air dose rate for a cumulative external exposure for 9000 1 km × 1 km mesh units incorporating 51 municipalities. The decontamination cost for the basic scenario, for which forested areas within 20 m of habitation areas were decontaminated, was JPY2.53-5.12 trillion; the resulting reduction in annual external dose was about 2500 person-Sv. The transport, storage, and administrative costs of decontamination waste and removed soil reached JPY1.55-2.12 trillion under this scenario. Although implementing decontamination of all forested areas provides some major reductions in the external radiation dose for the average inhabitant, decontamination costs could potentially exceed JPY16 trillion. These results indicate that technologies for reducing the volume of decontamination waste and removed soil should be considered to reduce storage costs and that further discussions about forest decontamination policies are needed.

Studies on residue-free decontaminants for chemical warfare agents.

Residue-free decontaminants based on hydrogen peroxide, which decomposes to water and oxygen in the environment, are examined as decontaminants for chemical warfare agents (CWA). For the apparent special case of CWA on concrete, H2O2 alone, without any additives, effectively decontaminates S-2-(diisopropylamino)ethyl O-ethyl methylphosphonothioate (VX), pinacolyl methylphosphorofluoridate (GD), and bis(2-choroethyl) sulfide (HD) in a process thought to involve H2O2 activation by surface-bound carbonates/bicarbonates (known H2O2 activators for CWA decontamination). A plethora of products are formed during the H2O2 decontamination of HD on concrete, and these are characterized by comparison to synthesized authentic compounds. As a potential residue-free decontaminant for surfaces other than concrete (or those lacking adsorbed carbonate/bicarbonate) H2O2 activation for CWA decontamination is feasible using residue-free NH3 and CO2 as demonstrated by reaction studies for VX, GD, and HD in homogeneous solution. Although H2O2/NH3/CO2 ("HPAC") decontaminants are active for CWA decontamination in solution, they require testing on actual surfaces of interest to assess their true efficacy for surface decontamination.

High-level endoscope disinfection processes in emerging economies: financial impact of manual process versus automated endoscope reprocessing.

BACKGROUND: The use of flexible endoscopes is growing rapidly around the world. Dominant approaches to high-level disinfection among resource-constrained countries include fully manual cleaning and disinfection and the use of automated endoscope reprocessors (AERs). Suboptimal reprocessing at any step can potentially lead to contamination, with consequences to patients and healthcare systems. AIM: To compare the potential results of guideline-recommended AERs to manual disinfection along three dimensions - productivity, need for endoscope repair, and infection transmission risk in India, China, and Russia. METHODS: Financial modelling using data from peer-reviewed published literature and country-specific market research. FINDINGS: In countries where revenue can be gained through productivity improvements, conversion to automated reprocessing has a positive direct impact on financial performance, paying back the capital investment within 14 months in China and seven months in Russia. In India, AER-generated savings and revenue offset nearly all of the additional operating costs needed to support automated reprocessing. CONCLUSION: Among endoscopy facilities in India and China, current survey-reported practices in endoscope reprocessing using manual soaking may place patients at risk of exposure to pathogens leading to infections. Conversion from manual soak to use of AERs, as recommended by the World Gastroenterology Organization, may generate cost and revenue offsets that could produce direct financial gains for some endoscopy units in Russia and China.

Responding to biological incidents--what are the current issues in remediation of the contaminated environment?

Since 2000 there have been a number of biological incidents resulting in environmental contamination with Bacillus anthracis, the causative agent of anthrax. These incidents include the US anthrax attacks in 2001, the US and UK drumming incidents in 2006-2008 and more recently, anthrax contamination of heroin in 2009/2010 and 2012/2013. Remediation techniques used to return environments to normal have varied between incidents, with different decontamination technologies being employed. Many factors need to be considered before a remediation strategy or recovery option can be implemented, including; cost, time (length of application), public perception of risk, and sampling strategies (and results) to name a few. These incidents have demonstrated that consolidated guidance for remediating biologically contaminated environments in the aftermath of a biological incident was required. The UK Recovery Handbook for Biological Incidents (UKRHBI) is a project led by Public Health England (PHE), formerly the Health Protection Agency (HPA) to provide guidance and advice on how to remediate the environment following a biological incident or outbreak of infection, and is expected to be published in 2015.

Cost and effectiveness of decontamination strategies in radiation contaminated areas in Fukushima in regard to external radiation dose.

The objective of the present study is to evaluate the cost and effectiveness of decontamination strategies in the special decontamination areas in Fukushima in regard to external radiation dose. A geographical information system (GIS) was used to relate the predicted external dose in the affected areas to the number of potential inhabitants and the land use in the areas. A comprehensive review of the costs of various decontamination methods was conducted as part of the analysis. The results indicate that aerial decontamination in the special decontamination areas in Fukushima would be effective for reducing the air dose rate to the target level in a short period of time in some but not all of the areas. In a standard scenario, analysis of cost and effectiveness suggests that decontamination costs for agricultural areas account for approximately 80% of the total decontamination cost, of which approximately 60% is associated with storage. In addition, the costs of decontamination per person per unit area are estimated to vary greatly. Appropriate selection of decontamination methods may significantly decrease decontamination costs, allowing more meaningful decontamination in terms of the limited budget. Our analysis can help in examining the prioritization of decontamination areas from the viewpoints of cost and effectiveness in reducing the external dose. Decontamination strategies should be determined according to air dose rates and future land-use plans.

Decontamination technology assessments - who assesses the assessments?

The driver to improve surgical instrument decontamination has been the introduction of vCJD into the UK population over the last two decades, although concerns over transmission of other infectious agents remain valid. Though significant improvements have been made in primary care, this is usually in spite of limited access to technical advice on decontamination equipment. A technology assessment for key elements of equipment and processes used in this environment should be welcomed. However, two reports by the Scottish Health Technology Assessment Panel are flawed in estimating costs associated with wrapping instruments, omission of appropriate references and inaccurate data in the costing models. These assessments contribute little to health economics debates, confuse practitioners and frustrate technical experts.

Decontamination of spent iron-oxide coated sand from filters used in arsenic removal.

Sand filters devised with iron-rich adsorbents are extensively promoted and deployed in the arsenic-prone south and south-east Asian countries (e.g., Bangladesh). The approach offers superior performance in removing arsenic while the spent sludge from the sand filters is an issue of concern due to the possibility of toxic releases after being discarded. In this work, a new technique is proposed for the treatment of spent iron-oxide coated sand (IOCS) from filters used in arsenic removal. Chelant-washing of the arsenic-loaded IOCS is combined with the solid phase extraction treatment to accomplish the objective. The unique point of the proposed process is the cost-effective scheme, which includes the option of recycling of the washing solvent beside the decontamination of the spent arsenic-rich sludge.