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Continuously active disinfection

In this webinar, we review the very new technology of continuously active disinfection (CAD) and how it differs from routine disinfection used in healthcare today.

Learning objectives:

  • Describe recent peer-reviewed articles assessing this technology in real-world and laboratory-controlled settings
  • Explore opportunities for using this technology and how to optimize return on investment
  • Discuss end-user and patient engagement
  • Review how to avoid potential unintended consequences

Presented by: Marc Oliver-Wright, MT (ASCP), MS, CIC, FAPIC Clinical Science Liaison, PDI Healthcare

Key topics:

  • Minute 00:40 – Introduction
  • Minute 4:15 – Traditional disinfection
  • Minute 10:50 – Continuously active disinfectants (CADs)
  • Minute 14:35 – U.S. Environmental Protection Agency (EPA) regulations
  • Minute 21:50 – EPA method for evaluating CADs
  • Minute 27:15 – Disinfecting non-dedicated patient care equipment
  • Minute 30:30 – What about viruses?
  • Minute 32:00 – Methods of evaluation
  • Minute 41:45 – Unintended consequences
  • Minute 53:15 – Summary and Q&A


Mary Beth: Hello and welcome to today's presentation, "Continuously active disinfection: A whole new world". I'm Mary Beth Gibney from McKesson. Today's webinar will be recorded and available for replay. You will also receive an email with directions for obtaining a continuing education credit from PDI for attending today's webinar. Our speaker today is Marc-Oliver Wright from PDI Healthcare, where he is the clinical science liaison for the central region. He's an expert in epidemiology and infection prevention. We are pleased to welcome Marc-Oliver today. Now I'll turn it over to him.

Marc-Oliver: Well, thank you, Mary Beth. And thank you to McKesson for offering me the opportunity to share some information with you today. So while you look over these disclosures, I'd like to provide some context as to why I'm particularly excited to talk about this. And no, it's not because I happen to work for a company that manufactures disinfectants. You know, anyone who spends any length of time in a career will likely have one or more moments in their career where their whole perspective on something related to their profession really changes, where they never look at the same topic or issue the same way as they did before. You know, arguably, we've all experienced an example of this over the past two or so years. An example from my own experience actually goes back to a conference called SHEA or the Society for Health Care Epidemiology of America in 2011. This is where Dr. Calvert, Carla Alvarado, introduced us all to the discipline of human factors engineering and how to use it in infection prevention. How I viewed performance improvement forever changed that day, and I remember exactly where I was in that audience. We're not always aware of the gravity of something when we first learn about it. Sometimes that realization comes weeks or months or even years later. And after having been involved with continuously active disinfectants over the past couple of years, I'm starting to think that this might be one as well. And if you're not already familiar with this topic yet, maybe the next hour will be one of those moments for you to.

So, to keep this in the time slot, I'm going to use the acronym CAD for continuously active disinfection or disinfectant CAD for short. Today we're going to describe the science of continuously active disinfection and differentiate it from traditional surface disinfection in healthcare today. We're going to summarize the published evidence supporting the use of CAD in a variety of health care settings. And we're going to identify specific settings where CAD may be of utmost importance and discuss the potential unintended consequences of using continuously active disinfection and importantly, how to avoid them. So this image shows how the contaminated environment can serve as a vector to the susceptible patient.

When we think about environmental contamination, many of us naturally think first and perhaps exclusively about the environment and of course, the susceptible patient. And as you can see, that's not without merit. Contaminated surfaces or equipment can and do serve as a direct source of transmission from surface to susceptible patient, as we show in that top red arrow. However, as importantly, and perhaps more so, these same surfaces can serve as the intermediary of transmission via contaminated hands. Most often, but not exclusively belonging to health care workers. The fact is, the more contaminated a surface, the more likely it can serve as a direct or indirect source for transmission. And while good hand hygiene in terms of both compliance and technique is essential, the fact remains that if we can limit the potential contamination to begin with, we can nullify some of the risk due to either poor compliance or poor technique.

But how do everyday disinfectant wipes and sprays and solutions work in your facility today? Well, let's say that you're a clinic manager for a pediatric clinic. You start out each day making sure that your common surfaces are disinfected. For example, the door handle to your front entrances wiped down with a health care grade, intermediate level disinfectant wipe for the proper wet kill or contact time. But then your clinic is open for business and that first patient comes and opens the door. And when they do so, they deposit some of the hundreds or thousands of organisms that are on their hands to the surface and they check in for their appointment. Well, then the second person comes in, transfers some of their own bacteria, and at the same time they pick up some from patient number one and the third from patients one and two and so forth. Until the next time you have a chance to disinfect the surface, [?] it's the ultimate take a penny leave a penny change jar at the entrance to your facility. Well, traditional surface disinfectants offer a near germ free result, but only at a single point in time. And this wouldn't be a problem if you were able to reapply the disinfectant at regular, scheduled and necessary intervals, whatever those might be.

But as I've shown here, there are some services where that probably doesn't happen. So there have been some emerging technologies over the years that have demonstrated continuously active disinfection technology. For example, there are UV wavelengths that, unlike supplemental room disinfection, are wavelength safe to use in the presence of humans. Safe for us, you know the bacterial fight over. This light based technology does seem to work, but it's far from rapid. It often takes hours. And rather than try to cover the litany of non-disinfectant or non-solution based options, I'm going to cover one just for the sake of an example. This comes to us from the world of heavy metals. And no, I'm not talking about Ozzy Osborne. We're we're talking about copper and silver coatings. The mechanism of action is incompletely understood, but it includes complete DNA degradation. And as such, it's speculated that bacteria will not develop tolerance or resistance to it. In one of the best, largest well designed studies evaluating this technology, researchers enrolled 414 patients in ICUs at three US based hospitals. They randomly and blindly allocated patients to rooms where several common high touch surfaces were coated with copper and her rooms where no such objects had copper coatings. And then they follow these patients forward in time to see which of them develops either healthcare associated infections during their hospitalization or acquired colonization with the multidrug resistant organisms that are known as MRSA or VRE.

Well, they concluded that their results showed that patients hospitalized in rooms with copper coated surfaces were significantly less likely to develop in HAI or become colonized with a multi-drug resistant organism. Since this study was first published in 2013, there have been a handful of additional investigations. Back in 2020, a meta analysis and systemic review looked at the published works to date, and they found seven studies to include in their meta analysis, and they determined that five of the seven were high risk of bias in selection bias, and all seven studies were judged to be at higher unclear risk from blinding of participants or personnel and conflict of interest. They concluded that there was insufficient evidence to make a strong, positive recommendation for adopting the technology more broadly. Well, in 2016, the Emergency Care Research Institute, or better known as ECRI, produced an emerging technology evidence report. They actually reanalyze the raw data presented by Salgado and colleagues in the preceding slides, and they found that, quote, the difference in the HAI rate, regardless of MRSA or VRE colonization status between the study groups, was not significant. With copper equipped ICUs having a 5.8% rate versus non-copper equipped ICUs having a 9.1% rate and a P value of 0.1 to 3. In other words, if you remove the effect of MDR colonization, infection rates were not significantly different, or more honestly, the study was underpowered to answer this question.

Well, then there's the cost. That same equity report sought to address this both at the individual item specific level, as shown in this table, as well as an overall estimate per in-patient room. And suffice to say, a 600 bed facility deploying $9 million in technology deemed to be of, quote, insufficient evidence is probably a bit of a stretch for a lot of c-suites. Lastly, and importantly for all manner of discussion as it relates to continuously active decontamination or disinfection, is that it does not negate the need for ongoing surface cleaning and disinfecting. In fact, according to the EPA, copper impregnated surfaces are quote a supplement to and not a substitute for standard infection control practices. Users must continue to follow all current infection control practices, including those practices related to cleaning and disinfection of environmental surfaces. Antimicrobial copper surfaces have reduced microbial contamination, but they do not necessarily prevent cross contamination. The EPA directions for use also indicate that antimicrobial copper surfaces should be cleaned and sanitized according to standard practices. So arguably, infection prevention is human factors dependent. That is, technology has to fit in fit within the confines of a recognized and established set of workflows. Disinfection using germicidal wipes or sprays is a well-established health care setting related workflow. And yet, as we saw earlier in this presentation, traditional health care disinfectants do not facilitate continuously active disinfection until now actually. According to the EPA, a continuously active disinfectant or residual efficacy solution has substantiated, quote, claims that a product provides an ongoing antimicrobial effect beyond the initial time of application, end quote.

When you combine a CAD with a traditional health care grade immediate use disinfectant, you get the immediate benefit of a quick kill, as is found with traditional surface disinfectants and lacking in either heavy metals or light based technologies, plus an ongoing antimicrobial effect. This might sound like something new, and that is in part because it is new. Yet the EPA has actually published specific criteria for evaluating such claims. I like this little visual image. I think it conveys the basics of continuously active disinfection pretty well as described with the clinic door handle. Current or traditional EPA registered disinfectants do not have an EPA validated residual activity claim, and therefore bacteria can re-contaminate that surface and they can do so basically any time after you walk away from wiping the surface down. But a continuously active disinfectant prevents bacterial contamination after being applied up to a specific time and or touches or abrasions to the surface. So we're going to get back to that in a second. But according to the EPA, the maximum allowable measures for efficacy testing is 24 hours or 96 touches. Well, at this point in the presentation, most people likely fall into one of three camps. There are those of you that accept the concept of CAD at face value.

Perhaps those of you that are skeptical but waiting to hear some evidence. And then those of you who might believe that I'm trying to get you to sell your last cow for three magic beans. I've been around long enough to see my fair share of snake oil solutions for infection prevention related problems. 

And skepticism is inherently part of the critical thinking that infection prevention is and other clinicians deployed day in day out. So how do we evaluate the evidence? Well, there's actually a hierarchy to doing this with any new technology, and it often starts with laboratory based studies, both during and after product development. But these are carefully controlled evaluations. I mean, they're conducted in the lab. And and while they are an essential first step, it doesn't take you to the giant's castle or hands of that goose that lays the golden eggs of success. The lab is not the real world. And I spent enough years working in the lab to say that. So new technologies such as this has to be evaluated in that setting as well, and in hospitals and long term care facilities, wherever the implied benefit of a CAD might be. Lastly, the technology can do what it claims, but if it doesn't benefit the patient, well, that's like asking the question. If a beanstalk falls in the forest and no one's around to hear, it doesn't actually make a sound. So let's start climbing. Let's see where it takes us.

But let's start with the EPA and how they evaluate these and other product claims. So as a refresher, the FDA regulates food, drugs and medical devices, among others. And in contrast, the EPA is responsible for the regulation of, among others, sterility sanitizer, surface disinfectants. Their regulation and testing stems largely from in-vitro studies or laboratory controlled studies, which I'm going to delve into in a second here. Manufacturers have to submit evidence to back up any claims, including prescribed testing with approval. The EPA specifies the language that can or must be used on a manufactured products labeling, and this can be termed the master label. The EPA master label is the end all, be all of truth. But as I alluded to, it allows within some very specific boundaries, some flexibility for the manufacturer to use on their production or canister label in marketing materials. But in the end, the master label contains all of the information and it's all well and good to look at that label on the pack or canister someone gave you as a sample. But I highly encourage you to get your hands on that master label, as well as there may be information that is not on the product or production label. And thankfully the EPA actually makes this easy to do. The website shown here allows anyone with an internet access and the name or EPA registration number of a product to seek out and find this one source of truth.

Also, it's important to note the master label may be updated while the EPA alphabet soup of lists. If you've heard about List K or List N or List P, they might be updated at a different time. A product may have a master label claim for a particular organism and not be listed on the corresponding EPA list. They operate on different time intervals. Again, master label is your one source of truth. And I mentioned so much of this on the master label because especially when it comes to wet or contact or kill times, that is the minimum amount of time that a hard non-porous service has to remain visibly wet or have the product be reapplied. The times can vary widely, so let's say a disinfectant has the following master label claims it kills E. Coli in 30 seconds, it kills Staph Aureus and Pseudomonas Aeruginosa and 2 minutes it kills C. Diff in 5 minutes. But the manufacturer opts to only list the three non-spore kill claims on the production label and they can and also list a wet contact kill time of 2 minutes, which is fine. Nothing wrong with that. As long as you don't try to use the product to kill C. Diff And it dries out in 3 minutes. To be considered a low level disinfectant, the product must be effective against Staph Aureus and Aeruginosa for intermediate level. It also has to have a claim against Mycobacterium Tuberculosis or TB.

Which brings me to how the EPA does allow some surrogate use of organisms. For example, most of the time Mycobacterium Bovis is used as a surrogate or marker for MTB, and similarly, Feline Calicivirus may be use as a surrogate for norovirus. Lastly, not only old bug will do the MTCC or Microbial Type Culture Collection is based in India and the ATCC or American Type Culture Collection is the US base and both are examples of world data centers for microorganisms. They provide the stock cultures of specific organisms for companies that test the effectiveness of their disinfectants on. So when you see this on a master label, that's what that number is actually referring to. Well, how does the EPA test disinfectants? Well, it depends on the formulation for liquids and portables and sprays. This little image provides a nice overview. Essentially, what's required is a use dilution method whereby 60 stainless steel cylinders or glass slides are inoculated with a specific pathogen. Then they are sprayed or immersed in test tubes that contain that liquid disinfectant for the specific wet contact or kill time, then removed from that solution, neutralize immediately and cultured onto media that is grown for 48 hours at 35 to 37 degrees centigrade. And if any organisms grow in that plate, the solution fails for that organism and that contact time. But the testing methods for wipes is different. It's similar, though, here. The EPA recommends 80, but they actually require 60 slides plus controls to be inoculated with the organism allowed to incubate or drive 30 to 40 minutes before the slides are wipe with a single towelette or wipe three times back and forth for a total of six passes between each wipe, thus users to fold the wipe to a new section. These two are then neutralized and then incubated for 48 hours at 35 to 37 degrees Celsius. And clearly there has to be a standard method for evaluating and testing disinfectant formulations.

And I can also understand how these methods can and should be different for different formulations, whether they're sprays or wipes or the next new thing. But when I look at these two kinds of procedures, I have to ask how closely these methods might match real clinical practice. But this is the process for each and every organism that gets a kill claim on an EPA master label. What does that mean for continuously active disinfectants? Well, there's actually a different process for CADs. These slides are credited to Dr. William Murtala. And while the images and content are not his per se, the the explanation for this process is gleaned from some of his earlier presentations, which are arguably much more understandable than in trying to interpret the EPA's 22 page document of instructions that I reference at the bottom here. So what are shown here are called abrasion testers. These instruments simulate a specific number of wears or abrasions as proxies for contacts or touches.

So with continuously active disinfectants, the evaluation is both time. Remember up to 24 hours and touches or abrasions. Also, if a CAD wants to attain a label claim for immediate use disinfection, it also has to meet the previously described criteria for the wipe or spray and liquid formulations. So as you can see, the similarities of testing methodology include the use of standardized inoculum of organisms. In this case, it has to include Staph Aureus and in Klebsiella Pneumoniae or Enterobacteriaceae, as well as any additional organisms. The manufacturer seeks to attain a label clean for that continuous disinfection. These are the specific requirements for evaluating a CAD. And while you read through it, I'll give you the short version OK.

You apply the continuously active disinfecting solution to a surface. You let it dry under specific time and humidity conditions, and then you set the abrasion tester that I showed you on the previous slide. To start simulating touches, you keep applying an inoculation of organisms over time. Usually about ten to the sixth in quantity. And with each application after the maximum allowable time of 24 hours, you remove, neutralize and culture the surface for organism growth. So importantly, that disinfectant that CAD solution was only applied once and it was applied 24 hours ago. And the capability of the CAD is based off of that last inoculation of organisms. So this is a study that was presented by Dr. Bertoli and colleagues in 2019 and the American Journal of Infection Control. They conducted this study in an EPA, in a laboratory based setting where they basically recreated the EPA requirements using some select epidemiologically important pathogens, namely, they use Staphylococcus Aureus, E Coli, Vancomycin Resistant Enterococcus or VRE, Klebsiella Pneumonia, Anaerobic Species, Candida Auris, CRE Coli Sierra stands for Carbapenem Resistant Enterobacteriaceae version of E Coli.

In other words, a drug resistant E Coli, a CRE Enterobacteriaceae, a CRE Klebsiella pneumoniae. Basically, most of the bad bugs you can imagine is causing health care associated infections. They evaluate a trial, continuously active disinfectant against two other hospital grade disinfectants and then simulated touches using that previously described the breader. What did they find? Well, first they found that the CAD had a more significant log reduction against the most common pathogen Staph Aureus than the other three immediate use disinfectants. And that's not surprising as the solution was already approved as a CAD or the others were not. Additionally, they found that different pathogens were impacted differently. While surprisingly that environmentally hardy Candida Auris was reduced greater than all other pathogens. Klebsiella pneumonia was not reduced more than 99.9%, which is not as much as some of the other pathogens that I list here. So that's all well and good. But a lab based study can only tell us so much. Researchers at the Medical University of South Carolina took the same solution that Dr. Atala used into a real world setting. They tested three disinfectants on the bedrails of occupied patient beds in the medical ICU. They then left these bed rails to the real world setting and came back and cultured those bed rails at one six and 24 hours after that initial and only application.

In the real world setting, the most contaminated surfaces, arguably the patient themselves, then the mattress, and then in a close third place, bed rails. So this represents not only the real world, but arguably one of the most contaminated real world settings. So what did they find? Well, they found that the CAD had a statistically significant benefit over and above both of the other commercially available quaternary ammonium based health care grade disinfectants at six and 24 hours and was actually superior to one of the two agents after only a single hour. They concluded that, quote, the agent evaluated here disinfectant one represents a first of its kind disinfectant that offers an ability to debunk the built environment of microbes while addressing the limitations inherent to the using EPA registered disinfectants for daily cleaning mainly mainly rebound to the biofilm affiliated with the surfaces or the introduction of new bio burdens secondary to the care and housing of patients. So this isn't a real world setting. What next? Well, hot off the press from that same type of conference. Shea Here in 2022, the Duke Group, including Dave Anderson, evaluated a CAD in an occupied patient rooms in a different, albeit interesting manner.

They took bed rails, bedside tables and hand hygiene, things of occupied patient rooms, patients who were on some form of isolation precautions, and they applied their routine disinfectant to one side of the surface and a CAD in the same CAD as previously described to the others as shown in this image. They returned 24 hours later and found that the CAD had 32% fewer total organisms recovered than the standard disinfectant on the same fixtures. Again, very much a real-world setting. And this is probably one of my favorites. Dr. Domanski and colleagues took it one step further. And when IPs or Infection Preventionist think about inanimate objects in their health care facilities and the frequency of cleaning and disinfection with respect to the need for cleaning and disinfection. Well, at least for me personally, non-dedicated patient care equipment has to come close to mine. These rolling items of microbiological wonder are long recognized sources of transmission and the need for and hindrance against adequate disinfection must keep a lot of IPs awake at night. That wheelchair that's rolling into room two. Well, how clean, actually, is it? That computer on wheels that goes from room to room during rounds? How likely are IPs to want that instrument going into the 10th or 30th room during morning rounds? Well, Dr. Donskoi and colleagues evaluated the continuously active disinfectant in an acute care facility, as well as a perhaps even more concerning long term care facility.

They randomized 114 portable pieces of non dedicated patient care equipment to undergo one of three possible strategies. Again, a very, very real world setting. The three standards, the three strategies were singularly done. In other words, they they did it once and then they walked away. They applied either the continuously active disinfectant or a traditional quat ammonium based disinfectant, health care grade, disinfecting the regular one. Or they did nothing at all and just recorded the the instrument. Then they returned these items to regular patient care or use. Importantly, they did not actually measure or monitor routine disinfection thereafter. What they did do was come back on days one, four and seven after applying the disinfectant a single time and measure both the percent of surfaces with Staph Aureus and Enterococcus species as as well as the total aerobic bacterial counts of all organisms otherwise known as CFUs or Colony Forming Units, the latter of which the CAD that they tested does not actually have an EPA master label clean for.

But what they find, perhaps by this point in the presentation, you might not be surprised to see that the percent of sites positive for the claimed organisms were significantly lower in the CAD disinfected equipment items than in either the traditional disinfectant nor the untreated items. What might surprise you, though, is that these results were through day seven, despite the aforementioned 24-hour claim.

And interestingly as well, and also not consistent with the EPA master label claims for the solutions. Overall total bacterial counts beyond Staphylococcus and Enterococcus was sustained through day seven as well and superseded both the routinely treated and untreated points at each day of measurement. Again, this was a single application and there was no monitoring of the activity that occurred afterwards. Well, the vast majority of evidence supporting the use of CADs is based on bacterial pathogen recovery. So naturally the question comes up what about other pathogens that we can play know, can play a role in transmission? And for example, what about viruses?

Well, if we look at the hierarchy of pathogens that's shown here, most envelope viruses are more susceptible to disinfectants than vegetative bacteria. And so it would not be too surprising if the CAD could impact them. Dr. Atala and colleagues published an article in the Journal of Infection Control and Hospital Epidemiology earlier this year evaluating this very question as it relates to human coronavirus 229 E, as well as the SARS-CoV-2 virus. And in a laboratory based setting, we evaluated the effectiveness of a CAD against these two viruses 48 hours after it was initially applied, and the same wear and abrasion technique that I have already described. And they compare its performance to a control of sterile water being used again. Viruses are pretty easy to kill, but here they found that the continuously active disinfectant had a sustained greater than four log reduction of viable virus, although this claim is not included on the CADs EPA master label.

But how do you know that this is going to work for you? Well, there's a few approaches to this. There is the trust but verify modality where you read and understand and accept the EPA master label claims and the peer reviewed literature. But there's also the approach that says, I need to see this for myself and in my own setting and my own facility. And with this latter approach, there are a few methods worth mentioning for what they can show and arguably what they can't. First, there's the topic of fluorescent marking. Well, this this is a common, relatively easy, relatively inexpensive method of evaluating surface cleaning and disinfection. It utilizes a fluorescent marker commonly less visible under normal light. But if fluorescent is under UV light, the individual, which is often an environmental services supervisor or it's an infection preventionist. What they do is they go around and they apply it to surfaces either in a room or on equipment before it's expected to be cleaned or disinfected, either as part of a daily clean or a terminal discharge. The person responsible for cleaning and disinfecting surfaces, preferably unknowingly performs their task in the same index. Individual or applicator of the marker comes back to the setting, uses a handheld fluorescent light or flashlight and checks to see whether or not the marks have been removed.

And it's simple, it's straightforward and largely a successful approach to monitoring and providing some qualitative feedback for the very human oriented task of cleaning and disinfecting. But and this is an important caveat, that fluorescent marker serves as a proxy for surface contamination. I mean, that spot, it's not bacteria. It's a glorified magic marker. It's good at indicating whether or not a surface contamination like dirt or body fluids would be removed. But it's not an indicator of disinfection. And furthermore, the removal of the marker is actually contingent on the surface itself as well as what I will call the substrate utilized. In other words, a brand new microfiber cloth is going to remove more of that mark than the same cloth towards the end of its functional usability when equal forces apply. And similarly, some substrates will perform better, like a microfiber cloth does really well, but they will perform better than others, like perhaps a disposable wipe or a paper towel, if you will. So not to cause any undue anxiety. But if you go back to Biochemistry 101 and review the Krebs Cycle or also known as the tricarboxylic acid cycle or adenosine triphosphate or ATPs, the byproduct of this energy producing cycle, ATP measurement devices have evolved over the last 30 years to the point where they are now handheld and their use was actually first recognized on the industry side as a useful tool for the food service industry to indicate whether food preparation areas had been adequately cleaned.

And it remains a common practice in the food industry to this day. However, it's important to note that evaluating the presence of organic matter is not the same as evaluating whether or not the same surface has been disinfected. ATP testing does not differentiate living and dead organisms, nor, for that matter, organisms from other organic material as described by the FDA. Quote An ATP test only gives a sense of how well something has been cleaned. For example, a prep table in a food processing facility could show high levels of ATP, meaning unclean surface, while providing a negative test result on a series of environmental pathogen tests. This is because ATP tests will register any organic matter on a surface, even if none of that organic matter is specifically pathogenic. End quote. Even if that none of that matter, organic matter is pathogenic. Well, despite its origins and food safety, ATP monitoring quickly expanded to the health care setting. It, as you can see here in a study presented by doctors, Fratello, Weber and colleagues back in 2017, there is a lack of correlation between ATP results and viable, measurable bacterial or viral organisms on a surface. Clean is clean, but it's not the same as germ free. In a similar study published just in 2021 by Van Arkle and colleagues in PLOS One, the authors found a weak correlation between ATP results and CF use on surfaces in health care facilities.

And they concluded that, quote, ATP measurement can be used to give a quantifiable outcome for the rating of cleanliness in health care facilities. However, the results cannot be translated into the level of microbial contamination, end quote, which actually reiterates the conclusion by Omi Box [?] And colleagues in 2014 in their PLOS One study that stated, quote, Introducing ATP meters to health care facilities as a disinfection validation tool is not a reliable choice, end quote. Well, a final application of when we measure we no better approach is to conduct microbiological sampling of the environment. There are some established ways to do this, but essentially you attempt to grow organisms from the environmental surface, preferably before and after application of the disinfectant or CAD, and then you measure the results. And while this this is the gold standard, it's not without its own potential pitfalls if you're comparing a standard disinfectant and a CAD. You want to make sure that the surfaces, utilization and touches or times are similar for both. You need to measure them the same way, but it's arguably superior to either fluorescent marking or ATB testing. And until recently, I was of the personal opinion that this was a reasonable approach for organizations to conduct their own validation of the EPA testing requirements and in peer reviewed published literature. But after speaking with Dr. Patel on the subject a couple of times, I've come to realize that that opinion of mine was based on biased, albeit well-intentioned, personal experience.

Before I started in infection prevention more than 20 years ago, I was a medical technologist, and I started my first career working in a hospital epidemiology laboratory for a well published and well respected researcher, an IP physician named Lance Petersen. Dr. Petersen often utilized environmental culturing in many of his research studies, and he expected his staff to know how to collect environmental cultures. So he personally trained us. And once you know what you're doing, it's relatively straightforward. But most laboratories and even most clinical microbiologists don't get this kind of training. And all of this is a way of saying that it's not sufficient to consult your friendly neighborhood microbiologist. You need someone who's experienced in the field of environmental sampling and microbiological methods. And if you don't, your methods may be flawed. And flawed methods yield flawed data. So in the absence of a robust design with in-house expertise, I recommend a trust but verify approach. Read that EPA master label thoroughly and read the published evidence in the literature with a critical eye. You'll find the flaws in the study designs. Nearly all published articles have flaws, but are they fatal flaws? And if not, the evidence can probably speak for itself. Back to the evidence and turning away from self evaluation. Thus far we've seen that there are options for a liquid and white formulation of a continuously active disinfectant.

We have seen the laboratory based studies as well as the EPA criteria for evaluation, and this answers the question Does continuously active do continuous active disinfectants perform as expected under control lab based conditions? Well, yeah, I would say yes, it does. Going beyond the controlled laboratory environment, we have some well performed studies in the real world and in the first case, bed rails of occupied patient beds were evaluated and they revealed that a CAD was superior to traditional immediate use disinfectants. In another, the researchers demonstrated efficacy of the same had to be superior to traditional use disinfectants as well as no treatment overall for actively utilized portable medical equipment. And we actually saw a third study that looked at this for bifurcated surfaces in in the same room and in the same setting and the same exposure between a traditional disinfectant and a CAD.

So two questions are left. Does the the use of continuously active disinfectant correlate with reduced transmission to patients? Well, while this has been demonstrated with the heavy metal impregnated objects that I reviewed earlier, this is pending for liquid and white formulations. But I can assure, assure you that these studies are forthcoming. The last question is whether or not there's the potential for unintended consequences for using such new technology.

So here's a hypothetical scenario for you. An acute care facility is undergoing its expected triennial accreditation survey. They use a continuously active disinfectant on multiple surfaces, including their portable medical equipment, because they read that study by Dr. Donskoy and colleagues in the survey are standing there one afternoon and observes the following The technician brings a portable EKG into room one for Patient A. After finishing the testing, they use the continuously active disinfectant, according to the manufacturer's IFU. That same technician takes that equipment to room three for patient C. But as they are finishing that test, the tech is called to room five for an urgent scan and recognizing that the CAD is effective for up to 24 hours, they don't disinfect the equipment prior to entering room five. Well, Citation Nation, what's your analyzation? If we return to that EPA statement for copper impregnated devices, they are a supplement to and not a substitute for standard infection control practices. Users must continue to follow all current infection control practices, including those practices related to cleaning and disinfecting environmental surfaces. So how do we avoid these and other potential issues? Well, arguably, the linchpin in infection prevention is communication. You can't just drop off a case of continuously active disinfectants into a setting and expect the label to explain it all. And for the overworked frontline care provider, a solution that says it keeps killing organisms for 24 hours is almost a license to cut corners. But for the US worker expected to clean and disinfect the common area twice per shift, it's easy to look at that label and say, No, I can't do that.

Second meaning it's critical to explain to end users what a CAD is, therefore, and what it does and what it does not do. And until or unless circumstances change, a CAD will not negate many standard operating procedures and policies of a piece of portable medical equipment is expected and by policy to be disinfected after each and every use. A CAD is not going to circumvent that requirement. It's again, to quote the EPA, a supplement to not a substitute for standard practice. But of course, the best way to reinforce practice is to continue or enhance monitoring and feedback to the the people that actually do the work. But to continue along this line, CAD is less about reducing need in the battle against organism transmission and infection. You need a sword, obviously. You always need a sword. The sort of strong policies and procedures, education and training, routine monitoring and feedback and the continuous act of disinfectant is not a sword. That's a shield. It's a shield of protection. You can go into battle with a sword and not a shield. And if you wield it well enough and dodge the hits, the shield helps a lot too, but it's rarely, if ever, enough on its own. When you're contemplating if and how to use a CAD, you would do well to remember Franz's Kafka's quote, everyone is necessarily the hero of their imagination first. For IPS, if we think about our environment, well, that's the wrong word to use, isn't it? For an infection, prevention is everywhere, in the environment, the entrance to our facilities, the patient transport equipment, the waiting room in the ED and the the public bathroom.

It's all the IPS environment. And with a statement like that, it's easy to feel overwhelmed. When overwhelmed, we have one, more or less one of three responses. We either panic because we don't know what to do, or we choke because we we know what we need to do, but we don't know how to do it. Or are we going to step back and reevaluate and move on from there? In the context of environmental cleaning and disinfection, we can panic or choke, but we can also just take a step back and reevaluate. So every disinfectant is different and continuously active disinfection disinfectants is not an exception. As as mentioned on the previous slide, CAD is a shield of protection. The price for that shield is that sometimes and on some surfaces, but definitely not all other. There might be an appearance of a residue left behind in pre age CADs days. This might have been perceived as less of an issue, but with questions like, quote, during this hospital stay, how often were your room and bathroom kept clean? This might be a bit of a concern. And if your solution is to wipe away that shield for appearance sake, you're effectively setting your shield down on the ground in the battlefield.

That's, that's not a good option. In this image, you might be able to see a slight residue to the areas that have been wiped with the CAD, that that residue is actually your shield. But to the untrained or unaware, that shield may appear on some surfaces as unwanted. Right. As health care quality outcomes have become more transparent, patients have actually become more savvy. Sometimes we underestimate patient and family abilities to comprehend change. But you know what? Good advertising works. It's why ads still sell out for the Super Bowl. And ultimately advertising is about messaging. So what do you do when the disinfectant you're using offers that shield of protection or the patient doesn't know it? Well, tell them. Tell them. Tell them what it is and why you're using it. What it does. Tell them in plain language. Change the narrative before they write their own story in that age gap survey. Instead of suggesting that some of the surfaces appeared unclean because there was a residue on the surface, let them know that the organization has adopted new technology to better protect them. When deploying a fluorescent marker. ATP monitoring program, IPS and environmental service supervisors are often required to enter occupied, seem to be discharged or transferred patient rooms. The 30 seconds that we spend telling the patients what we're doing there reinforces the patient that the organization takes cleaning and disinfecting and ultimately safety seriously.

So much so that they take time to measure it. And that changes the perception, the messaging of what cleaning and disinfecting looks like. CAD may not be conducive to all surfaces or all settings. So rather than panic or choke, let's take a step back. Arguably, the best way to start is with surfaces or settings that are not prone or available to cleaning and disinfection as often as you would like. The first thing that came to my mind when I first heard about this technology was waiting areas. The emergency department waiting area is probably one of the most challenging environments to get in and clean or disinfect at any point in time during the day, and certainly not without the degree of frequency as we would like to in a setting of limitless time and resources. And similarly, many ambulatory care waiting areas are disinfected once a day, often at night. Conference rooms in classrooms, well arguably frequented by staff more than patients or visitors are are similarly, but understandably, a lower priority for regular disinfection. While public restrooms might be attended to more frequently, their degree of utilization might make this another option. Recently, researchers headed up by Dr. Curtis Dansk conducted a prevalence survey of environmental contamination in four Cleveland area hospitals and five outpatient facilities. Specifically, they cultured surfaces outside of the inpatient room, and we often think about environmental cleaning and contamination as being highest in acute inpatient rooms.

That's probably true, but this doesn't mean that surfaces outside these areas are germ free. In fact, in hospitals, nearly 10% of these surfaces outside of patient rooms were contaminated with a multidrug resistant organism, and nearly 6% were positive for fungal species or candida species. While the outpatient setting, more than 6% of sites were positive for a multidrug resistant organism and 10% were positive for fungal organisms. Other surfaces are settings are worth considering, but with important caveats. Dining areas, both for staff as well as visitors, might be conducive to carry the EPA required [?]. Oh might be conducive to a CAD, but many disinfectants, including continuously active disinfectants, carry that EPA required verbiage. Quote, A potable water rinse is required for food contact surfaces, end quote. But the important phrase in the statement is not potable water rinse, which again would actually negate the benefits of CAD, but the phrase food contact surfaces. Interestingly, what's the food contact service? Well, the Food and Drug Administration actually has a definition. It says food contact surfaces are those surfaces, quote, that contact human food and those surfaces from which drainage onto the food or onto surfaces that contact the food. Ordinarily occurs during the normal course of operations. Food contact surfaces includes utensils and food contact surfaces of equipment. End quote. A dining room table is not arguably a food contact surface, unlike the tray of a high chair in a daycare setting at lunchtime. No one or hopefully no one is eating their food off of your table.

They're eating off of plates, using utensils or trays, none of which you would contemplate using a CAD on. And the next two images are worth mentioning as well. Doorknobs, elevator buttons, etc.. Yeah, these are certainly high touch objects and yes, they are certainly not disinfected enough throughout the day. But the evaluation of CAD includes an element of both time and abrasions or touches. And depending on that surface, you may not want to automatically assume that a single application every 24 hours is sufficient. If, for example, you're like me and you press the elevator button not once but four times because you're impatient. But a CAD would certainly be better than an immediate use disinfectant. Other surfaces are settings are worth considering, but with important caveats. The dining areas both for. Sorry. I lost my train of thought there, the medical transport setting. These are tightly compacted, high, complex, high turnover settings that are often difficult to clean and disinfect them as often as they need to. You have the perioperative space in the between case turnover that occurs and arguably the immediate area of the sterile area of the procedure definitely needs to be continuously or needs to be disinfected between cases. But the question is, is the perimeter of the room that's not necessarily soiled during the case, does that warrant the same between case turnover efforts? But ultimately with these new frontiers are are ask is going to have to be is the juice, if you will, worth the squeeze.

So in summary, how continuously active disinfectants are EPA registered differentiated solutions that extend antimicrobial activity beyond their initial application, and they regularly outperform traditional immediate use disinfectants both in the laboratory based conditions as well as in some real-world settings, as has been previously reported. Evidence supporting the efficacy of CAD has been demonstrated in the lab, and traditional methods of quantifying and evaluating efficacy of health care. Cleaning and disinfection may not be conducive to evaluating CAD technology. You need to carefully prioritize and select surfaces or settings for CAD optimization, and then these can and should include underserved and high traffic areas, and you can mitigate potential unintended consequences through effective and proactive end user and customer communication.

McKesson representatives will be providing you with these instructions in a follow up email. So there's no need for you to go writing this down in order to obtain your continuing education credits for this presentation. Thank you for attending today's session. Thank you again to McKesson for this opportunity. If there's time remaining, I'm very happy to address any questions in the chat. And of course, if we're up against the hour, I will, as I mentioned at the start of this session, be providing McKesson with a detailed, written response to all unanswered questions, which can be shared with all participants in a follow up email from them.

Mary Beth: Thank you so much, Mark and PDI, for a wonderful presentation today. And we don't have. We don't have any any specific questions, just kind comments about what a great presentation this was. And I agree. And as a reminder, you can find a list of upcoming webinars on our website. And then next stop, McKesson dot com educational webinars. Thank you again to Mark and PDI and thank you all for attending. Have a great rest of your day.

Webinar originally aired on August 3, 2022

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