Doe Kley, MPH, RN, T-CHEST, LTC-CIP, CIC, discusses how environmental hygiene supports efforts to contain antimicrobial resistance, examining disinfectant efficacy, dilution failures, shared equipment, and the partnership between infection prevention and environmental services teams.
A disinfectant dispenser that fails to deliver the correct concentration. Shared equipment that moves between patients without a clear cleaning responsibility. A restricted department where environmental services personnel cannot enter. These are the kinds of gaps Doe Kley, MPH, RN, T-CHEST, LTC-CIP, CIC, asks infection prevention and environmental services teams to investigate when evaluating their environmental hygiene programs.
In this interview with Infection Control Today® (ICT®), Kley discusses the distinction between antibiotic resistance and disinfectant efficacy, the practical challenges that can undermine cleaning, and the importance of shared accountability. Drawing on research and her experience in infection prevention, she explains why attention to everyday processes belongs in the broader conversation about antimicrobial resistance. “Everyone has a role in preventing transmission,” Kley says. Her message to EVS professionals is equally direct: “Effective environmental hygiene isn't a supporting role in this fight - it's a frontline intervention.”
ICT: You open by saying the post-antimicrobial era "isn't coming, it's here." For someone outside health care, what does that look like day-to-day? And what convinced you that it's already happening rather than a future risk?
Doe Kley, MPH, RN, T-CHEST, LTC-CIP, CIC, infection prevention fellow of clinical and scientific affairs for Clorox Purell ProCare: That's the CDC's language, not mine—and I use it because the data backs it up. You know, resistance is rising faster than we can answer it. In the last decade, only about 22 new antibiotics reached the market. In contrast, up to 50 new drugs are coming out each year for things like diabetes, depression, and even weight loss.
Meanwhile, antibiotic resistance climbed nearly 40% between 2018 and 2023. Did you know that in the US, 1 in 7 bacterial infections is now resistant, costing about 48,000 lives and $5.7 billion a year? And what’s scarier is that by the year 2050, experts predict that AMR [antimicrobial resistance] will kill more people than all cancers combined.
But what convinced me isn't the projection of AMR; it's the history. Methicillin came into widespread use in 1959, and the first resistant [Staphylococcus] appeared in 1960, just 1 year later. Consider that bacteria reproduce roughly every 20 minutes, whereas we humans only reproduce maybe twice in a lifetime. This replication speed is directly tied to how quickly antimicrobial resistance can emerge and spread. The math was never in our favor. What's at stake isn't just treating infections; it's whether surgery, transplants, and chemotherapy remain safe to perform.
ICT: Most people hear "antibiotic resistance" and think about overprescribing. You argue that the hospital environment itself is half the story. How did you come to that view, and what do surfaces and shared equipment contribute that prescribing habits can't explain?
DK: So antibiotic stewardship is essential, but it's only part of the solution, and here's what gets missed: Resistant organisms don't just live and replicate inside the patient’s body; they live and replicate on surfaces.
For perspective, a
Prescribing habits can't explain that. What prescribing also can't explain is gene sharing. While these organisms sit in the environment, they trade resistance genes with unrelated bacterial species. So, the environment isn't just a reservoir; it's where resistance spreads and evolves.
ICT: One of your central points was that antimicrobial resistance does not equate to disinfectant resistance. Why does that misconception persist, and what changes for infection preventionists and EVS teams once they truly understand the difference?
DK: This myth persists because the word "resistant" does a lot of work in people's minds. If an organism defeats our best antibiotics, it feels obvious that it must be harder to kill on a surface. It's an intuitive leap, but it's wrong.
Antibiotics are precise—1 lock, 1 key, hitting a single target, at a dose that has to stay safe inside the human body. That precision is exactly the weakness of antibiotics. At the same time, disinfectants aren't precise at all. They destroy the cell membrane, denature proteins, and cause oxidative stress, all at once. And because they're used on surfaces, we can apply them at concentrations far above those needed to kill.
In our internal testing under good laboratory practice (GLP), we compared wild-type strains with their antibiotic-resistant counterparts. Across 55 paired results, disinfectant efficacy was consistent between wild-type and resistant strains when label instructions were followed. These findings indicate that when a disinfectant holds an [US Environmental Protection Agency] EPA-registered efficacy claim for a strain of a given bacterium, the absence of a specific claim for the resistant variant doesn’t imply diminished effectiveness against it.
The importance of this becomes clear when we realize that these pathogens can evolve faster than disinfectant manufacturers can complete EPA testing and update labels. This process can take several years. What changes when we understand that antibiotic resistance does not equate to disinfectant resistance is confidence. A team that understands this stops hesitating over whether their product is "strong enough" for a pathogen like [Carbapenem-Resistant Enterobacterales]CRE and can focus more on what actually determines the outcome—doing the process right. That's why I say this distinction empowers IPs and EVS to act decisively.
ICT: If true disinfectant resistance is rare, why does disinfection still fail — and what does that say about where hospitals should be putting their attention: products, process, or people?
DK: I can tell you that it’s almost always a process problem, not the organism. Things like incorrect dilution, failure to observe contact time, or just poor technique. But the good news is that every one of these is within our control.
But I'd push back gently on framing it as products vs process vs people, because they interact.
So, the answer is to design the process so humans can't easily get it wrong. In other words, make the right thing, be the easy thing to do. Monitor your dilution systems. Where you can, use ready-to-use products where dilution error isn't possible, and recognize the gap EVS can't close alone. For example,
I can share a quick story on my experience in the hospital with dilution systems, and I know they have their place, but what I had noticed in my surveillance was our C difficile rates.
I had a 6-floor hospital, with several units on each floor. On one of my floors, I had noticed that C difficile had jumped. So on a couple of units, but all on the same floor. Everyone else had remained at the super low C difficile rate. I thought, " What the heck is going on on that floor? Being an IP, I wandered up to the floor, and I was snooping and walking around doing what IPs do, and I ran into my EVS worker up there.
We were chit-chatting, and I happened to have some pH strips in my pocket, my lab coat pocket, and I stuck them in her bucket of disinfectant, and when I pulled them out, they showed it was just straight water, and both of our eyes were out of our heads. Poor girl probably thought she was going to lose her job, and we even smelled it, smelled like the product.
I said, "Let's go back and make a fresh bucket. So, we did, straight water. We knew Houston, we had a problem, and it was the dispenser. It was not dispensing the proper dilution. Fortunately, the manufacturer only came in quarterly to check the dispensers, so we had to have our supervisors do a pH test at least daily.
However, we put that in place, and it quickly fell apart because they were just too busy running. You can imagine how many EVS closets there are in a medium-sized hospital, and we only had 2 or 3 supervisors on the day shift, so the fix we put in place quickly fell by the wayside. They were not checking them daily, but we did stick with that product for the time being.
That's a real example of it happening, and it happens a lot. You can't just trust.
I got the sense this year at AHE that EVS is becoming more accepting of the concept of ready-to-use products. You know, they're a little bit more expensive up front because they're prepared for you. You don't have to dilute. They're ready to go, but they do make the right thing to do, the easy thing to do. They're convenient, and the product. Many of the products on the market work very well. They're superior. I feel like EVS is definitely more open to this concept.
ICT: You built the session around a scenario in which a team must choose the most appropriate disinfectant for a room that housed a patient with NDM-1 Klebsiella. What did you want people to take away from that moment of choosing, and how do audiences typically respond?
DK: Ahh, yes, the scenario-based activity using branched decision-making paths! I wanted participants to feel the hesitation. In the scenario, the room held a patient who had tested positive for NDM-1 Klebsiella—a type of CRE, the nightmare bacteria—and there were 2 products on the EVS cart.
Disinfectant #1 had no Klebsiella claim, and while disinfectant #2 (a ready-to-use sporicidal) had a Klebsiella claim, it did not have an
That pause is the whole lesson. You don't need an NDM-1-specific claim. The claim for the susceptible strain covers the resistant one. And the sporicidal wipe wins in every other dimension too: a broader spectrum, faster contact time, and no risk of dilution error.
Audiences respond well because it's not abstract; they see the consequence play out. In the first path, the next patient admitted to the room acquires the NDM-1 pathogen. In the second path, the patient goes home in just 3 days with no complications. When participants make the choice themselves, it lands differently than when they are told the principle.
ICT: You recommend a sporicidal disinfectant for every discharge clean, not just isolation rooms. That's a real workflow shift. How do you make that case to a skeptical hospital leader, and what evidence moves them?
DK: I would start by defining the problem, which, in this case, is that we simply don’t know. Meaning, we don’t always know what pathogens a patient may have been harboring.
We only apply enhanced measures when we're aware a patient is carrying something, but all too often we are not aware until sometime later, and the damage is already done. In the scenario I used in this presentation, the patient wasn't even on contact precautions until the culture came back on the day of discharge. And that's not unusual.
To convince my leadership, I would lean into the available evidence. I would point to the plethora of studies that have demonstrated the risk to the next patient admitted to a room previously occupied by a patient colonized or infected with a drug-resistant or a C difficile infection. These studies have demonstrated that the risk can be up to 3.5 times higher than had the prior occupant not been harboring a drug-resistant pathogen.
Another study worth sharing is a 2019 Donskey study, which showed that when bleach replaced the quat for all discharge cleans, C difficile contamination in non-C difficile rooms dropped from 24% to 5%.
I would also share this important data that always gets a leader’s attention: the human and financial costs of AMR infections, which are associated with up to 70% higher mortality, up to 24% longer stays, and roughly 29% higher costs.
Finally, I would remind the leadership team that cleaning with a sporicidal agent is the highest level of clean you can offer the next patient admitted to a room. Remember, sporicidal disinfectants are considered intermediate-level disinfection—just 1 step below high-level disinfection and 1 step above low-level disinfection.
ICT: You shared a personal story that reminded participants not to overlook ancillary departments. Can you reshare that story here for us?
Absolutely! At my last hospital, I had wandered down to Radiology, where MRIs are performed. As you know, this is a highly restricted area for safety reasons. You know, those magnets don’t play around! It's so restricted that I asked the radiology manager about cleaning. I learned they didn’t even permit EVS in the space! Rather, the radiology staff, untrained in C&D, were doing the cleaning!
Guess how they mopped the floors? They dropped disinfecting wipes on the floor and shuffled around the room with their feet!
Obviously, as an IP, this was completely unacceptable, so working together:
The key takeaway from this story is that IPs and EVS must look behind every door in every department!
ICT: What's the one thing you'd want every EVS professional to hear from this: what's their role in preserving antibiotics for the next generation?
DK: I want them to know how absolutely vital their role is in patient safety. You know, IPs and EVS professionals don't prescribe antibiotics — but they certainly help protect them. Every transmission prevented is potentially a life saved and an antibiotic preserved for someone who'll need it, possibly even years from now. Effective environmental hygiene isn't a supporting role in this fight - it's a frontline intervention working on 2 fronts: preventing infections so fewer antibiotics get used and containing resistance so it doesn't reach the next patient.
(Edited for readability and length)
