Is the combination of UV-C light and bleach less effective than bleach alone for intensive care unit surface disinfection?

Background

Chlorine-based disinfectants, such as bleach, are commonly used for cleaning in healthcare settings to prevent the transmission of nosocomial pathogens. To enhance the efficacy of disinfection, ultraviolet-C (UV-C) light systems have been proposed to supplement standard cleaning procedures. As bleach decomposes in UV light, we hypothesised that the use of UV-C light as an adjunct to manual cleaning with bleach, may decrease the efficacy of disinfection instead.

Methods

In the laboratory, stainless steel sheets and plastic keyboards were inoculated with Pseudomonas aeruginosa (∼106 CFU/ml) and subjected to treatment with either UV-C light only, bleach only or a combination of UV-C light and bleach. The residual bioburden (CFU/ml) was quantified through conventional microbiological techniques. Results were compared to non-exposed control surfaces and against each treatment strategy.

Results

On tested surfaces, there were statistically significant reductions in P. aeruginosa when surfaces were treated with UV-C light only (>2.5 log10 reduction), bleach only (>5.6 log10 reduction) and a combination of UV-C light and bleach (>6.3 log10 reduction) compared to positive control (P < 0.001, all treatment strategies). No significant differences were observed when surfaces were treated with the addition of UV-C light to bleach compared to treatment with bleach alone.

Conclusion

There was no difference in the efficacy of disinfection against P. aeruginosa with the combined treatment strategy of UV-C light and bleach compared to bleach alone under laboratory conditions. Further studies are warranted to elucidate the effectiveness of this technology on other healthcare-associated pathogens.

Impact of test methodology on the efficacy of triethylene glycol (Grignard Pure) against bacteriophage MS2

The COVID-19 pandemic has raised interest in using chemical air treatments as part of a strategy to reduce the risk of disease transmission, but more information is needed to characterize their efficacy at scales translatable to applied settings and to develop standardized test methods for characterizing the performance of these products. Grignard Pure, a triethylene glycol (TEG) active ingredient air treatment, was evaluated using two different test protocols in a large bioaerosol test chamber and observed to inactivate bacteriophage MS2 in air (up to 99.9% at 90 min) and on surfaces (up to 99% at 90 min) at a concentration of approximately 1.2 - 1.5 mg/m3. Introducing bioaerosol into a TEG-charged chamber led to overall greater reductions compared to when TEG was introduced into a bioaerosol-charged chamber, although the differences in efficacy against airborne MS2 were only significant in the first 15 min. Time-matched control conditions (no TEG present) and replicate tests for each condition were essential for characterizing treatment efficacy. These findings suggest that chemical air treatments could be effective in reducing the air and surface concentrations of infectious pathogens in occupied spaces, although standard methods are needed for evaluating their efficacy and comparing results across studies. The potential health impacts of chronic exposure to chemicals should also be considered, but those were not evaluated here.

Disinfection, sterilization and antisepsis: An overview

BACKGROUND

Each year in the United States there are approximately 100,000,000 outpatient/inpatient surgical procedures. Each of these procedures involves contact by a medical device or surgical instrument with a patient's sterile tissue and/or mucous membrane. A major risk of all such procedures is the introduction of infection.

METHODS

We searched published literature for articles on the use and effectiveness of disinfectants, sterilization methods and antiseptics.

RESULTS

The level of disinfection is dependent on the intended use of the object: critical (items that contact sterile tissue such as surgical instruments), semicritical (items that contact mucous membrane such as endoscopes), and noncritical (devices that contact only intact skin such as stethoscopes) items require sterilization, high-level disinfection and low-level disinfection, respectively. Cleaning must always precede high-level disinfection and sterilization. Antiseptics are essential to infection prevention as part of a hand hygiene program as well as other uses such as surgical hand antisepsis and pre-operative patient skin preparation.

CONCLUSIONS

When properly used, disinfection and sterilization can ensure the safe use of invasive and non-invasive medical devices. Cleaning should always precede high-level disinfection and sterilization. Strict adherence to current disinfection and sterilization guidelines is essential to prevent patient infections and exposures to infectious agents.

Multimodal environmental cleaning strategies to prevent healthcare-associated infections

Infection transmission in healthcare is multifaceted and by in large involves the complex interplay between a pathogen, a host and their environment. To prevent transmission, infection prevention strategies must also consider these complexities and incorporate targeted interventions aimed at all possible transmission pathways. One strategy to prevent and control infection is environmental cleaning. There are many aspects to an environmental cleaning strategy. We believe the key to successfully reducing the risk of healthcare-associated infections through the environment, is to design and implement a multimodal intervention. This paper aims to provide an overview of important considerations for designing a meaningful and sustainable environmental program for healthcare facilities.

Large-scale evaluation of microorganism inactivation by bipolar ionization and photocatalytic devices

The COVID-19 pandemic has raised awareness in the spread of disease via airborne transmission. As a result, there has been increasing interest in technologies that claim to reduce concentrations of airborne pathogens in indoor environments. The efficacy of many of these emerging technologies is not fully understood, and the testing that has been done is often conducted at a small scale and not representative of applied settings. There is currently no standard test method for evaluating air treatment technologies, making it difficult to compare results across studies or technology types. Here, a consistent testing approach in an operational-scale test chamber with a mock recirculating heating, ventilation, and air conditioning (HVAC) system was used to evaluate the efficacy of bipolar ionization and photocatalytic devices against the non-enveloped bacteriophage MS2 in the air and on surfaces. Statistically significant differences between replicate sets of technology tests and control tests (without technologies active) are apparent after 1 h, ranging to a maximum of 0.88 log₁₀ reduction for the bipolar ionization tests and 1.8 log₁₀ reduction for the photocatalytic device tests. It should be noted that ozone concentrations were elevated above background concentrations in the test chamber during the photocatalytic device testing. No significant differences were observed between control and technology tests in terms of the amount of MS2 deposited or inactivated on surfaces during testing. A standardized, large-scale testing approach, with replicate testing and time-matched control conditions, is necessary for contextualizing laboratory efficacy results, translating them to real-world conditions, and for facilitating technology comparisons.

Inhibition of microbial pathogens in farmed fish

Aquaculture, also known as aqua farming, is defined as farming fish, crustaceans, mollusks, aquatic plants, algae, and other marine organisms. It includes cultivating fresh- and saltwater populations under controlled conditions compared to commercial fishing or wild fish harvesting. Worldwide, carp, salmon, tilapia, and catfish are the most common fish species used in fish farming in descending order. Disinfectants prevent and/or treat different infections in aquatic animals. The current review indicates the uses of different disinfectants against some important pathogens in aquaculture, with particular reference to tilapia (Oreochromis niloticus) farming. A single review cannot cover all aspects of disinfection throughout aquaculture, so the procedures and principles of disinfection in tilapia farming/aquaculture have been chosen for illustration purposes.

Evidence Map and Systematic Review of Disinfection Efficacy on Environmental Surfaces in Healthcare Facilities

Healthcare-associated infections (HAIs) contribute to patient morbidity and mortality with an estimated 1.7 million infections and 99,000 deaths costing USD $28-34 billion annually in the United States alone. There is little understanding as to if current environmental surface disinfection practices reduce pathogen load, and subsequently HAIs, in critical care settings. This evidence map includes a systematic review on the efficacy of disinfecting environmental surfaces in healthcare facilities. We screened 17,064 abstracts, 635 full texts, and included 181 articles for data extraction and study quality assessment. We reviewed ten disinfectant types and compared disinfectants with respect to study design, outcome organism, and fourteen indictors of study quality. We found important areas for improvement and gaps in the research related to study design, implementation, and analysis. Implementation of disinfection, a determinant of disinfection outcomes, was not measured in most studies and few studies assessed fungi or viruses. Assessing and comparing disinfection efficacy was impeded by study heterogeneity; however, we catalogued the outcomes and results for each disinfection type. We concluded that guidelines for disinfectant use are primarily based on laboratory data rather than a systematic review of in situ disinfection efficacy. It is critically important for practitioners and researchers to consider system-level efficacy and not just the efficacy of the disinfectant.

Optimizing Operating Parameters of Electric Ultra-Low Volume Sprayer with Slightly Acidic Electrolyzed Solution for Efficient Virucidal Activity on Environmental Surfaces

Recently, and considering the COVID-19 pandemic, there has been a growing consensus that the disinfection of surfaces contaminated with pathogenic viral particles is essential. Chemical disinfectant sprays are effective at preventing the spread of infectious human noroviruses (Hu-NoVs) in healthcare and public areas. We assessed the virucidal activity of slightly acidic electrolyzed water (SAEW) spray on fomite surfaces. A multivariate statistical assessment that combined a response surface methodology (RSM) and a Box–Behnken design (BBD) was performed to define the optimal parameters of, and correlations among, experimental conditions. Spraying SAEW disinfectant (oxidation-reduction potential: 1123 mV, pH range: 5.12, available chlorine concentration: 33.22 ppm) resulted in the successful decontamination of Hu-NoV, with a 4-log reduction in viral particles on polyvinyl chloride, stainless steel, ceramic tile, and glass surfaces. Our experimental data revealed optimized treatment conditions for decontaminating Hu-NoV GI.6 and GII.4, using the numerical multiple optimized method (spraying rate: 218 mL/min, spraying time: 4.9 s, spraying distance: 0.9 m). These findings offer significant insights for designing optimal strategic control practices to prevent infectious disease, particularly Hu-NoV, transmission.

Health Care Environmental Hygiene: New Insights and Centers for Disease Control and Prevention Guidance

Recent research has significantly clarified the impact of optimizing patient-zone environmental hygiene. New insights into the environmental microbial epidemiology of many hospital-associated pathogens, especially Clostridioides difficile, have clarified and quantified the role of ongoing occult pathogen transmission from the near-patient environment. The recent development of safe, broadly effective surface chemical disinfectants has led to new opportunities to broadly enhance environmental hygiene in all health care settings. The Centers for Disease Control and Prevention has recently developed a detailed guidance to assist all health care settings in implementing optimized programs to mitigate health care-associated pathogen transmission from the near-patient surfaces.

Managing the Health of Captive Herds of Exotic Companion Mammals

Common medical problems diagnosed and treated in individual companion exotic mammals are relevant in a herd-health setting. Many of these problems are often associated with poor husbandry and/or inappropriate nutrition. Rabbits, ferrets, chinchillas, and rodents have been domesticated alongside humans and an understanding of their ethology gives veterinarians a base knowledge in making recommendations for animals in their care. This article briefly reviews the ethology and husbandry in such species, but detailed needs are beyond the scope of this article.

Infection Prevention in the Era of COVID-19: 2021 Basic Procedure Review

Infection prevention and control practices represent a vital behavioral skill set, especially in the era of COVID-19. Standard precautions, correct use of personal protective equipment, proper hand hygiene, and appropriate cleaning and disinfecting are necessary to prevent health-care-acquired infections in care facilities.

The effectiveness of a nonalcoholic disinfectant containing metal ions, with broad antimicrobial activity

Disinfectants have different efficacies depending on their use and the target microorganism. This study aimed to evaluate the efficacy and safety of our new nonalcoholic disinfectant, which consists mainly of metal ions. According to the 17th revised Japanese Pharmacopoeia and ASTM international E1052 method, the bactericidal and virucidal efficacy of this new disinfectant against 13 microorganisms was evaluated by the in vitro quantitative suspension test. Additionally, the disinfectant cytotoxicity against multiple cell lines was examined. Then, a safety test using a human open patch test was performed with 26 healthy volunteers. This disinfectant showed strong bactericidal and virucidal activities: all microorganisms except enterovirus were inactivated very quickly. The infectivity of 12 microbial strains was eliminated within 5 min of disinfectant exposure. Additionally, this disinfectant showed little acute cytotoxicity in vitro. All volunteers were negative in the human open patch test. Our new disinfectant has a broad spectrum of microbial targets, is safe for human skin, and demonstrates no cytotoxicity. This disinfectant could prevent common microbial infections.

A review of wipes used to disinfect hard surfaces in health care facilities

BACKGROUND

Despite a plethora of wipes available for use in health care facilities, there is a paucity of articles describing wipe composition, potential interactions between wipes and disinfectants, the manner in which wipes are used, and their relative efficacy. The purpose of this article is to provide an in-depth review of wipes used for disinfection of hard surfaces in health care settings.

METHODS

Comprehensive searches of the Pubmed database and Internet were conducted, and articles published from 1953 through September 2019 and pertinent on-line documents were reviewed. Bibliographies of relevant articles were reviewed.

RESULTS

Wipes vary considerably in their composition, and the disinfectants with which they are used. With reusable dry wipes, the ratio of wipe material to disinfectant and the amount of disinfectant absorbed by the wipe and delivered to surfaces is difficult to standardize, which may affect their efficacy. The manner in which wipes are used by health care personnel is highly variable, due in part to insufficient instructions for use and inadequate education of relevant personnel.

CONCLUSIONS

Additional research is needed regarding the best practices for using different types of wipes, improved methods for educating staff, and establishing the relative efficacy of wipes in reducing environmental contamination and health care-associated infections.

Virucidal Action Mechanism of Alcohol and Divalent Cations Against Human Adenovirus

Hygiene and disinfection practices play an important role at preventing spread of viral infections in household, industrial and clinical settings. Although formulations based on >70% ethanol are virucidal, there is a currently a need to reformulate products with much lower alcohol concentrations. It has been reported that zinc can increase the virucidal activity of alcohols, although the reasons for such potentiation is unclear. One approach in developing virucidal formulations is to understand the mechanisms of action of active ingredients and formulation excipients. Here, we investigated the virucidal activity of alcohol (40% w/v) and zinc sulfate (0.1% w/v) combinations and their impact on a human adenovirus (HAdV) using, nucleic acid integrity assays, atomic force microscopy (AFM) and transmission electron microscopy (TEM). We observed no difference in virucidal activity (5 log₁₀ reduction in 60 min) against between an ethanol only based formulation and a formulation combining ethanol and zinc salt. Furthermore, TEM imaging showed that the ethanol only formulation produced gross capsid damage, whilst zinc-based formulation or formulation combining both ethanol and zinc did not affect HAdV DNA. Unexpectedly, the addition of nickel salt (5 mM NiCl₂) to the ethanol-zinc formulation contributed to a weakening of the capsid and alteration of the capsid mechanics exemplified by AFM imaging, together with structural capsid damage. The addition of zinc sulfate to the ethanol formulation did not add the formulation efficacy, but the unexpected mechanistic synergy between NiCl₂ and the ethanol formulation opens an interesting perspective for the possible potentiation of an alcohol-based formulation. Furthermore, we show that AFM can be an important tool for understanding the mechanistic impact of virucidal formulation.

Considerations for the Selection and Use of Disinfectants Against SARS-CoV-2 in a Health Care Setting

Proper disinfection using adequate disinfecting agents will be necessary for infection control strategies against coronavirus disease 2019 (COVID-19). However, limited guidance exists on effective surface disinfectants or best practices for their use against severe acute respiratory coronavirus 2. We outlined a process of fully characterizing over 350 products on the Environmental Protection Agency List N, including pH, method of delivery, indication for equipment sterilization, and purchase availability. We then developed a streamlined set of guidelines to help rapidly evaluate and select suitable disinfectants from List N, including practicality, efficacy, safety, and cost/availability. This resource guides the evaluation of ideal disinfectants amidst practical considerations posed by the COVID-19 pandemic.

Influence of drying time on prewetted disinfectant towelettes to disinfect glass surfaces

The use of prewetted disinfectant towelettes in health care settings proves challenging because they may dry quickly, reducing disinfection. This study examined the drying time of various commercial disinfectant towelettes and the efficacy of these towelettes over time to eliminate Staphylococcus aureus from glass surfaces. This study confirms that these disinfectants dry quickly. Further disinfection after drying time on glass is minimal, but dependent on the type of disinfectant.

Ways in which healthcare interior environments are associated with perceived safety against infectious diseases and coping behaviours

BACKGROUND

Global pandemic outbreaks are a cause of fear. Healthcare workers (HCWs), especially those fighting the pathogens at the front line, are at higher risk of being infected while they treat patients. In addition, various environmental fomites in hospitals, which may carry infectious agents, can increase the risk of acquiring an infectious disease.

AIM

In order to deliver the best healthcare practice, it is critical that HCWs feel safe and protected against infectious diseases. The aim of this study was to improve understanding of HCWs' hand hygiene (HH) behaviours and perceptions of infectious diseases from a psychological perspective.

METHODS

Environmental features were observed in three departments, and questionnaires were used to determine perceived safety against infectious diseases among HCWs and the coping behaviours they used (e.g. avoidance and disinfection).

FINDINGS

This study found that an increase in the number of HH stations at convenient locations would increase HH compliance and perceived safety against infectious diseases among HCWs. In response to the current research gap in psychological aspects associated with HH, this study found that HCWs' coping behaviours can be predicted by their perceived likelihood of contamination and perceived vulnerability.

CONCLUSIONS

The study findings should be interpreted with care, and further studies with more academic rigor are needed.

A Review of the Differential Diagnosis of Acute Infectious Conjunctivitis: Implications for Treatment and Management

The diagnosis of acute infectious conjunctivitis can be difficult. Clinical ambiguity exists between the acute viral and bacterial as well as the allergic forms, which can confound diagnosis. Also, discrimination between viral or bacterial origins of infectious conjunctivitis based on historical, nonspecific, clinical signs and symptoms contributes to a high rate of misdiagnosis and overuse of antibiotic treatment. Therefore, in order to effectively treat acute infectious conjunctivitis, physicians must be aware of the clinical signs and symptoms and available diagnostic tests that can provide a more accurate differential diagnosis.

Clinical Issues-March 2020

Laundering microfiber cleaning supplies Key words: cloth, mop, microfiber, laundering, microorganisms. Significance of contact time during cleaning Key words: disinfectant, contact time, cleaning, bactericidal efficacy. Mask use during cystoscopy and tonsillectomy procedures Key words: surgical mask, splash, exposure, barrier level, blood-contaminated aerosols. Use of radiopaque towels Key words: radiopaque towels, radiopaque markers, soft goods, towel retention. Personal fragrances in the perioperative setting Key words: fragrances, fragrance sensitivity, asthma, disability.

Antimicrobial Activity of Cold Plasma Treatment on Acrylic Denture Bases: An In Vitro Evaluation

Introduction: Cross-contamination between dental office and prosthetic laboratories is of utmost importance. The dental prosthesis could harbor tones of microorganisms harmful to health staff. It has been estimated that more than 60% of the prostheses delivered to clinics from laboratories or vice versa are contaminated with pathogenic microorganisms. Several disinfection methods and chemicals have been proposed for sanitizing prostheses. Cold plasma, or nonthermal plasma, has been introduced as a new method in medical equipment disinfection. The current study aimed to compare the antimicrobial effect of cold plasma and the routinely used alcohol-based impression disinfectant ASEPTOPRINT® on disinfecting dentures. Methods: In this experimental study, 30 maxillary complete dentures were used as the microbial source. Dentures were randomly divided into 3 groups: (1) cold plasma treatment for 30 seconds, (2) cold plasma for 60 seconds, (3) ASEPTOPRINT® spray. Microbial culturing was taken before and after disinfection in each group on both Blood Agar plates and Soborou Dextrose Agar (SDA) plates. After 48 hours incubation at 37°C, the number of colonies was counted using a digital colony counter and differences between the groups were analyzed. Results: A significant reduction in microbial colonies was observed after using all disinfection methods. ASEPTOPRINT® spray showed more antimicrobial effects comparing to cold plasma. Conclusion: The antimicrobial effect of ASEPTOPRINT® spray solution is more than cold plasma application on both microbial and fungal microorganisms. The time of plasma application was not accompanied by any significant differences in the results.

Use of Ultraviolet Irradiation in Addition to Commonly Used Hospital Disinfectants or Cleaners Further Reduces the Bioburden on High-Touch Surfaces

Background

The reduction in microbial bioburden achieved by terminal disinfection in a hospital may vary considerably by type of disinfectant or cleaner and by environmental service (EVS) personnel. This study estimated whether supplemental ultraviolet (UV) irradiation after disinfection or cleaning reduced bioburden and whether the supplemental effect persisted after adjusting for disinfectant or cleaner type and EVS personnel.

Methods

Environmental samples for aerobic bacterial colonies (ABC) and methicillin-resistant Staphylococcus aureus (MRSA) were obtained from 5 high-touch surfaces in patient rooms at 3 time points: before manual cleaning, after manual cleaning using 1 of 3 disinfectants or 1 cleaner, and after UV irradiation.

Results

For ABC, the model-estimated mean (95% uncertainty interval) counts were 56% (48%-63%) lower for postmanual + UV compared with manual clean alone, and for MRSA they were 93% (62%-99%) lower for postmanual + UV vs manual clean alone.

Conclusions

Although UV supplementation provides incremental benefit in bioburden reduction across all cleaners or disinfectants tested, it provides the greatest benefit when supplementing cleaners or disinfectants with the lowest disinfection properties. UV irradiation provides additional bioburden reduction to manual cleaning or disinfection, even when accounting for variability introduced by different disinfectants and EVS personnel.

Surface Disinfection

The patient-care areas in a dental setting become contaminated with bacterial and viral pathogens during patient treatment. Incorporating standard precautions set forth by CDC and OSHA guidelines will reduce the risk of disease transmission. Contaminated environmental surfaces, including clinical contact and housekeeping surfaces, become a reservoir of infectious material with the potential to spread an infection to health-care personnel and patients. Transmission of pathogens can occur by direct or indirect contact of clinical contact surfaces and the hands of health-care personnel. Proper infection control protocol of these surfaces includes cleaning, disinfecting, and the use of barriers to prevent the spread of infectious pathogens.

This chapter will provide an overview of the disinfection protocol of environmental surfaces in the dental setting. The topics include the various chemical formulations of hospital disinfectants and their proper use, as well as physical barriers that aim to reduce the degree of contamination in the dental treatment area thus decreasing the probability of cross-infection and disease transmission.

Best practices for disinfection of noncritical environmental surfaces and equipment in health care facilities: A bundle approach

Over the past decade, there is excellent evidence in the scientific literature that contaminated environmental surfaces and noncritical patient care items play an important role in the transmission of several key health care-associated pathogens including methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Acinetobacter, norovirus, and Clostridium difficile. Thus, surface disinfection of noncritical environmental surfaces and medical devices is one of the infection prevention strategies to prevent pathogen transmission. This article will discuss a bundle approach to facilitate effective surface cleaning and disinfection in health care facilities. A bundle is a set of evidence-based practices, generally 3-5, that when performed collectively and reliably have been proven to improve patient outcomes. This bundle has 5 components and the science associated with each component will be addressed. These components are: creating evidence-based policies and procedures; selection of appropriate cleaning and disinfecting products; educating staff to include environmental services, patient equipment, and nursing; monitoring compliance (eg, thoroughness of cleaning, product use) with feedback (ie, just in time coaching); and implementing a "no touch" room decontamination technology and to ensure compliance for patients on contact and enteric precautions. This article will also discuss new technologies (eg, continuous room decontamination technology) that may enhance our infection prevention strategies in the future.

Disinfection, sterilization, and antisepsis: An overview

All invasive procedures involve contact by a medical device or surgical instrument with a patient's sterile tissue or mucous membranes. The level of disinfection or sterilization is dependent on the intended use of the object. Critical (items that contact sterile tissue, such as surgical instruments), semicritical (items that contact mucous membranes, such as endoscopes), and noncritical (devices that contact only intact skin, such as stethoscopes) items require sterilization, high-level disinfection, and low-level disinfection, respectively. Cleaning must always precede high-level disinfection and sterilization. Antiseptics are essential to infection prevention as part of a hand hygiene program, as well as other uses, such as surgical hand antisepsis and preoperative skin preparation.

Impact of a probiotic-based hospital sanitation on antimicrobial resistance and HAI-associated antimicrobial consumption and costs: a multicenter study

Purpose

Antimicrobial resistance (AMR) is one of the major threats to human health, and the high frequency of resistant pathogens in the hospital environment can contribute to the transmission of difficult-to-treat health care-associated infections (HAIs). We recently reported that, compared with conventional chemical cleaning, the use of a microbial-based sanitation strategy (Probiotic Cleaning Hygiene System [PCHS]) was associated with remodulation of hospital microbiota and reduction of HAI incidence. Here, we aimed to analyze the impact of PCHS on AMR and related effects, such as HAI-associated antimicrobial drug consumption and costs.

Patients and methods

Five Italian hospitals, enrolled in a multicenter study where conventional sanitation methods were replaced with PCHS, were included in the analysis. The study period included a 6-month observation for each sanitation type. Surface microbiota AMR was analyzed using microarray, nested PCR, antibiogram, and microdilution tests. Drug consumption data and related costs were obtained from the medical records of all hospitalized patients affected by HAIs.

Results

PCHS use was associated with up to 99% decrease of the AMR genes harbored by surface hospital microbiota, independently of the resistance types originally present in each individual setting (P_c<0.01). Functional assays confirmed the molecular data, demonstrating a 33%–100% decrease of resistant strains depending on the antibiotic type. Antimicrobial drug consumption associated with HAI onset showed a global 60.3% decrease, with a 75.4% decrease of the associated costs.

Conclusion

The spread of AMR in the hospital environment can be limited by the use of sanitation methods to remodulate the hospital microbiota, leading to lower antimicrobial consumption and costs. This approach might be considered as part of broader infection prevention and control strategies.

Microbial transmission in an outpatient clinic and impact of an intervention with an ethanol-based disinfectant

Background

Halting the spread of harmful microbes requires an understanding of their transmission via hands and fomites. Previous studies explored acute and long-term care environments but not outpatient clinics. Objectives of this study were to track microbial movement throughout an outpatient clinic and evaluate the impact of a disinfectant spray intervention targeting high-touch point surfaces.

Methods

At the start of the clinic day, a harmless viral tracer was placed onto 2 fomites: a patient room door handle and front desk pen. Patient care, cleaning, and hand hygiene practices continued as usual. Facility fomites (n = 19), staff hands (n = 4), and patient hands (n = 3-4) were sampled after 2, 3.5, and 6 hours. Tracer concentrations at baseline (before intervention) were evaluated 6 hours after seeding. For the intervention trials, high-touch surfaces were cleaned 4 hours after seeding with an ethanol-based disinfectant and sampled 2 hours after cleaning.

Results

At 2, 3.5, and 6 hours after seeding, virus was detected on all surfaces and hands sampled, with examination room door handles and nurses’ station chair arms yielding the highest concentrations. Virus concentrations decreased by 94.1% after the disinfectant spray intervention (P = .001).

Conclusions

Microbes spread quickly in an outpatient clinic, reaching maximum contamination levels 2 hours after inoculation, with the highest contamination on examination room door handles and nurses’ station chairs. This study emphasizes the importance of targeted disinfection of high-touch surfaces.

The Role of the Environment and Colonization in Healthcare-Associated Infections

Healthcare-associated infections (HAIs) can be caused by endogenous host microbial flora or by exogenous microbes, including those found in the hospital environment. Efforts to decrease endogenous pathogens via decolonization and skin antisepsis may decrease the risk of infection in some settings. Controlling the spread of potential pathogens from the environment requires meticulous attention to cleaning and disinfection practices. In addition to selection of the appropriate cleaning agent, use of tools that assess the adequacy of cleaning and addition of no-touch cleaning technology may decrease environmental contamination. Hand hygiene is also a critical component of preventing transmission of pathogens from the environment to patients via healthcare worker hands.

There is no additional bactericidal efficacy of Environmental Protection Agency-registered disinfectant towelettes after surface drying or beyond label contact time

BACKGROUND

Disinfectant towelettes are commonly used for surface disinfection to prevent health care-associated infections; however, there is limited consensus as to whether a surface needs to remain wet for the full label contact time after the disinfectant towelette has been used in order for complete efficacy to be achieved. The purpose of this study was to quantify the effect of contact time, including times before and after a product dries, on bactericidal efficacy of 6 towelette products registered by the Environmental Protection Agency .

METHODS

Six disinfectant towelette products were tested at varying contact times, including defined label contact times. Quantitative Environmental Protection Agency MB-33-00 was used to measure disinfectant efficacy against Staphylococcus aureus on Formica. Complete dry time for each disinfectant was measured gravimetrically.

RESULTS

There were significant differences in dry times among the towelette products; contact time did not have a significant effect on bactericidal efficacy. There was no longitudinal effect when a disinfectant's contact time was greater than defined label contact time, irrespective of whether the product was wet or dry on the surface.

DISCUSSION

Overall, bactericidal efficacy varied by towelette product tested and surface area wiped. Wiping larger surface areas may lead to decreased bactericidal efficacy but is product dependent.

CONCLUSIONS

There was no additional bactericidal effect after a product dried, indicating that extended contact times beyond when the product dries will not enhance disinfection.

An Innovative Strategy for the Effective Reduction of MDR Pathogens from the Nosocomial Environment

Antimicrobial resistance (AMR) is currently one of the main concerns for human health.Due to its rapid increase and global diffusion, several common microbial infections might become not curable in the future decades, making it impossible to apply other lifesaver therapies, such as transplant or chemotherapy.AMR is frequently observed in hospital pathogens, due to selective pressure exerted by antibiotic use, and consistently with this, in the recent years, many actions have been proposed to limit AMR spread, including hygiene measures for hospital professionals and a wiser antibiotic usage.Indeed, the hospital environment itself represents a reservoir of pathogens, whose control was so far addressed by conventional sanitation procedures, which however cannot prevent recontamination and might further favour the selection of resistant strains.Here we report the results collected by studying an innovative sanitation strategy based on the use of probiotic bacteria, capable of reducing in a stable way the surface load of pathogens and their AMR. Collected data suggest that this system might contribute significantly to AMR control and might be thus considered as one of the tools for AMR and infection prevention and control.

Evaluation of the antimicrobial efficacy and skin safety of a novel color additive in combination with chlorine disinfectants

OBJECTIVE

A novel color additive colorizes chlorine disinfectants blue to improve visibility and enhance spray surface coverage, and it fades to colorless to indicate elapsed contact time. We investigated its interactions with 3 chlorine disinfectants to determine if the additive would adversely affect the disinfectants' antimicrobial efficacy or skin safety.

METHODS

We tested 0.5% sodium hypochlorite, 0.2% calcium hypochlorite, and 0.5% sodium dichloroisocyanurate (NaDCC) alone versus with color additive. An independent laboratory tested efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, Vibrio cholerae, and human coronavirus 229E. An independent laboratory also tested direct skin irritation.

RESULTS

Chlorine disinfectants with and without color additive achieved equal levels of efficacy against the tested pathogens. Against S. aureus, 0.5% sodium hypochlorite with and without color additive met Environmental Protection Agency criteria for disinfection success. Against human coronavirus 229E, 0.5% sodium hypochlorite alone failed disinfection success criteria, whereas 0.5% sodium hypochlorite with color additive achieved full viral inactivation (≥4.50 log₁₀ reduction). Against V. cholerae, 0.2% calcium hypochlorite alone and with color additive achieved 5.99 log₁₀ and >6.03 log₁₀ reductions, respectively. Against S. aureus and P. aeruginosa, 0.5% NaDCC with and without color additive achieved >4.9 log₁₀ and >3.54 log₁₀ reductions, respectively. All 3 chlorine disinfectants with color additive tested as negligible skin irritants.

CONCLUSIONS

This color additive can be combined with chlorine disinfectants without adversely affecting antimicrobial efficacy or skin safety.

Surface area wiped, product type, and target strain impact bactericidal efficacy of ready-to-use disinfectant Towelettes

Background

Disinfectant products are often used on environmental surfaces (e.g. countertops, patient beds) and patient care equipment in healthcare facilities to help prevent the transmission of healthcare-associated infections. Ready-to-use (RTU) disinfectants in the form of pre-wetted towelettes are increasingly popular among healthcare facilities. Currently, the EPA does not require disinfectant manufacturers to include a recommended maximum surface area per towelette on their product labels. The objective of this study was to investigate the efficacy of disinfectant towelette products on a hard non-porous surface across different coverage areas using a quantitative EPA method. We hypothesized that there would be significant differences in the efficacy of disinfectant towelette products, and that the greater surface area(s) wiped would result in reduced bactericidal efficacy.

Methods

This study tested ten disinfectant towelette products against Staphylococcus aureus strain ATCC CRM-6538 and Pseudomonas aeruginosa strain ATCC 15442 on Formica surfaces. Defined surface areas were wiped and the towelette weighed before and after wiping to determine the amount of liquid released. Bactericidal efficacy testing was also performed after wiping following standard EPA protocols.

Results

We found that disinfectant product, area of surface wiped, and strain impacted the bactericidal efficacy achieved. Disinfectant product type and area of surface wiped significantly impacted the percent of liquid released per ft²from the towelette.

Conclusion

Overall, bactericidal efficacy varied by towelette product, surface area wiped, and strain. This study also found that wiping larger surface areas may lead to decreased bactericidal efficacy. Further research is needed to test its implication.

Randomized, Controlled, Phase 2 Trial of Povidone-Iodine/Dexamethasone Ophthalmic Suspension for Treatment of Adenoviral Conjunctivitis

PURPOSE

To evaluate the efficacy/safety of an ophthalmic suspension of povidone-iodine (PVP-I) 0.6% and dexamethasone 0.1% in patients with acute adenoviral conjunctivitis.

DESIGN

Multicenter, randomized, vehicle-controlled, double-masked trial.

METHODS

Adults with a positive Rapid Pathogen Screening Adeno-Detector Plus test were randomized 1:1:1 to PVP-I 0.6%/dexamethasone 0.1%, PVP-I 0.6%, or vehicle, bilaterally 4 times daily for 5 days (days 1-5). Patients were evaluated on days 3, 6, and 12 (+1-day window). Efficacy measures included clinical resolution and adenoviral eradication.

RESULTS

Overall, 144 patients were included in the efficacy analysis (PVP-I/dexamethasone, n = 48; PVP-I, n = 50; vehicle, n = 46). The proportion of patients with clinical resolution (primary study eye with last observation carried forward [LOCF]) at the day 6 visit was higher with PVP-I/dexamethasone (31.3%) than with vehicle (10.9%; P = .0158) and PVP-I (18.0%; P = nonsignificant). The proportion with adenoviral eradication (primary study eye with LOCF) was higher with PVP-I/dexamethasone than with vehicle at the day 3 (35.4% vs 8.7%; P = .0019) and day 6 (79.2% vs 56.5%; P = .0186) visits and vs PVP-I (day 3 visit, 32.0%; day 6 visit, 62.0%; each P = nonsignificant). Treatment-emergent adverse events (AEs) occurred in 69.0% (vehicle), 62.7% (PVP-I), and 53.4% (PVP-I/dexamethasone) of patients in the safety dataset. Discontinuation owing to AEs occurred in 37 patients (vehicle, n = 16; PVP-I, n = 12; PVP-I/dexamethasone, n = 9).

CONCLUSION

PVP-I/dexamethasone appeared safe and well tolerated, and significantly improved clinical resolution and adenoviral eradication in patients with acute adenoviral conjunctivitis.

Novel color additive for chlorine disinfectants corrects deficiencies in spray surface coverage and wet-contact time and checks for correct chlorine concentration

Bleach sprays suffer from poor surface coverage, dry out before reaching proper contact time, and can be inadvertently over-diluted to ineffective concentrations. Highlight^®, a novel color additive for bleach that fades to indicate elapsed contact time, maintained >99.9% surface coverage over full contact time and checked for correct chlorine concentration.

Reducing healthcare-associated infections incidence by a probiotic-based sanitation system: A multicentre, prospective, intervention study

Healthcare Associated Infections (HAI) are a global concern, further threatened by the increasing drug resistance of HAI-associated pathogens. On the other hand, persistent contamination of hospital surfaces contributes to HAI transmission, and it is not efficiently controlled by conventional cleaning, which does not prevent recontamination, has a high environmental impact and can favour selection of drug-resistant microbial strains. In the search for effective approaches, an eco-sustainable probiotic-based cleaning system (Probiotic Cleaning Hygiene System, PCHS) was recently shown to stably abate surface pathogens, without selecting antibiotic-resistant species. The aim of this study was to determine whether PCHS application could impact on HAI incidence. A multicentre, pre-post interventional study was performed for 18 months in the Internal Medicine wards of six Italian public hospitals (January 1st 2016-June 30th 2017). The intervention consisted of the substitution of conventional sanitation with PCHS, maintaining unaltered any other procedure influencing HAI control. HAI incidence in the pre and post-intervention period was the main outcome measure. Surface bioburden was also analyzed in parallel. Globally, 11,842 patients and 24,875 environmental samples were surveyed. PCHS was associated with a significant decrease of HAI cumulative incidence from a global 4.8% (284 patients with HAI over 5,930 total patients) to 2.3% (128 patients with HAI over 5,531 total patients) (OR = 0.44, CI 95% 0.35-0.54) (P<0.0001). Concurrently, PCHS was associated with a stable decrease of surface pathogens, compared to conventional sanitation (mean decrease 83%, range 70-96.3%), accompanied by a concurrent up to 2 Log drop of surface microbiota drug-resistance genes (P<0.0001; Pc = 0.008). Our study provides findings which support the impact of a sanitation procedure on HAI incidence, showing that the use of a probiotic-based environmental intervention can be associated with a significant decrease of the risk to contract a HAI during hospitalization. Once confirmed in larger experiences and other target populations, this eco-sustainable approach might be considered as a part of infection control and prevention (IPC) strategies. Trial registration-ISRCTN International Clinical Trials Registry, ISRCTN58986947.

Germicidal Activity against Carbapenem/Colistin-Resistant Enterobacteriaceae Using a Quantitative Carrier Test Method

Susceptibility to germicides for carbapenem/colistin-resistant Enterobacteriaceae is poorly described. We investigated the efficacy of multiple germicides against these emerging antibiotic-resistant pathogens using the disc-based quantitative carrier test method that can produce results more similar to those encountered in health care settings than a suspension test. Our study results demonstrated that germicides commonly used in health care facilities likely will be effective against carbapenem/colistin-resistant Enterobacteriaceae when used appropriately in health care facilities.

The Role of Patient Care Items as a Fomite in Healthcare-Associated Outbreaks and Infection Prevention

Patient-care items can serve as a source or reservoir for healthcare-associated pathogens in hospitals. We reviewed healthcare- associated outbreaks from medical equipment and provide infection prevention recommendations. Multiple healthcare-associated outbreaks via a contaminated patient-care item were identified, including infections with multidrug-resistant organisms. The type of patient care items implicated as a fomite causing healthcare-associated infections (HAIs) has changed over time. Patient populations at risk were most commonly critically ill patients in adult and neonatal intensive care units. Most fomite related healthcare-associated outbreaks were due to inappropriate disinfection practices. Repeated healthcare-associated outbreaks via medical equipment highlight the need for infectious disease professionals to understand that fomites/medical devices may be a source of HAIs. The introduction of new and more complex medical devices will likely increase the risk that such devices serve as a source of HAIs. Assuring appropriate cleaning and disinfection or sterilization of medical equipment is necessary to prevent future fomite-associated outbreaks.

Alcohols as Surface Disinfectants in Healthcare Settings

Isopropyl alcohol and ethyl alcohol have been used as low-level disinfectants in healthcare settings for many years. Recent studies have found that ethyl alcohol inhibits protein synthesis in Escherichia coli by direct effects on ribosomes and RNA polymerase and that 60%-70% solutions have in vitro efficacy against murine norovirus, Ebola virus, and several coronaviruses. Alcohol prep pads or towelettes containing isopropyl or ethyl alcohol and water have been used primarily for disinfection of small noncritical items due to a concern regarding their rapid evaporation rates and associated short contact times. Sterile alcohol solutions are used mostly for disinfection of compounding pharmacies and controlled areas. One new Environmental Protection Agency (EPA)-registered cleaner/disinfectant formulation differs from other alcohol-based disinfectants by virtue of having a 30-second contact time for multiple pathogens and a toxicity rating of category IV. Multiple disinfectants containing ethyl alcohol and/or isopropyl alcohol combined with other active agents such as quaternary ammonium or phenolic compounds are widely used for disinfecting environmental surfaces in healthcare facilities. Infect Control Hosp Epidemiol 2018;39:323-328.

How are nursing homes cleaned? Results of a survey of 6 nursing homes in Southeast Michigan

This brief report details 2 surveys that were conducted to better understand current cleaning practices in 6 nursing home facilities in Southeast Michigan. Each facility's environmental services supervisor answered questions regarding cleaning policy and procedures, roles and responsibilities of the staff, and frequency of education and training; one environmental services employee from each facility answered questions addressing education and training, employer evaluation and feedback, and workload. We identify gaps in knowledge and behaviors and note substantial variations in cleaning practices.

Prospective cluster controlled crossover trial to compare the impact of an improved hydrogen peroxide disinfectant and a quaternary ammonium-based disinfectant on surface contamination and health care outcomes

BACKGROUND

Quaternary ammonium-based (Quat) disinfectants are widely used, but they have disadvantages.

METHODS

This was a 12-month prospective cluster controlled crossover trial. On 4 wards, housekeepers performed daily cleaning using a disinfectant containing either 0.5% improved hydrogen peroxide (IHP) or Quat. Each month, 5-8 high-touch surfaces in several patient rooms on each ward were tagged with a fluorescent marker and cultured before and after cleaning. Hand hygiene compliance rates and antimicrobial usage on study wards were obtained from hospital records. Outcomes included aerobic colony counts (ACCs), percent of wiped surfaces yielding no growth after cleaning, and a composite outcome of incidence densities of nosocomial acquisition and infection caused by vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, and Clostridium difficile infection. Statistical analysis was performed using χ² test, Fisher exact test, Welch test, and logistic regression methods.

RESULTS

Mean ACCs per surface after cleaning were significantly lower with IHP (14.0) than with Quat (22.2) (P = .003). The proportion of surfaces yielding no growth after cleaning was significantly greater with IHP (240/500; 48%) than with Quat (182/517; 35.2%) (P < .0001). Composite incidence density of nosocomial colonization or infection with IHP (8.0) was lower than with Quat (10.3) (incidence rate ratio, 0.77; P = .068; 95% confidence interval, 0.579-1.029).

CONCLUSIONS

Compared with a Quat disinfectant, the IHP disinfectant significantly reduced surface contamination and reduced a composite colonization or infection outcome.

Decontamination of Hospital Surfaces With Multijet Cold Plasma: A Method to Enhance Infection Prevention and Control?

OBJECTIVE

To evaluate the efficacy of a multijet cold-plasma system and its efficacy in decontaminating 2 surfaces commonly found in hospitals

DESIGN

An in vitro study of common causes of healthcare-acquired infection

METHODS

Log10 9 cultures of methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, extended spectrum β-lactamase–producing Escherichia coli, and Acinetobacter baumannii were applied to 5-cm2 sections of stainless steel and mattress. Human serum albumin (HSA) was used as a proxy marker for organic material, and atomic force microscopy (AFM) was used to study the impact on bacterial cell structure. The inoculated surfaces were exposed to a cold-air-plasma–generating multijet prototype for 15, 20, 30, and 45 seconds.

RESULTS

After 45 seconds, at least 3 to 4 log reductions were achieved for all bacteria on the mattress, while 3 to 6 log reductions were observed on stainless steel. The presence of HSA had no appreciable effect on bacterial eradication. The surfaces with bacteria exposed to AFM showed significant morphological changes indicative of “etching” due to the action of highly charged ions produced by the plasma.

CONCLUSION

This multijet cold-plasma prototype has the potential to augment current environmental decontamination approaches but needs further evaluation in a clinical setting to confirm its effectiveness.

Infect Control Hosp Epidemiol 2017;38:1182–1187

Evaluation of a Novel Alcohol-Based Surface Disinfectant for Disinfection of Hard and Soft Surfaces in Healthcare Facilities

We examined the efficacy of a new 1-step cleaner and disinfectant containing 30% ethanol that is applied as a spray. The product rapidly reduced vegetative bacterial pathogens on carriers and on hard and soft surfaces in healthcare settings, but it did not stain clothing.