Biofilm is a global problem lurking in drains everywhere. It can be found in healthcare settings, laundries, sinks, schools and even in home drains.
During this PerfectCLEAN Clean Matters podcast, Dealing with Biofilm, host Michelle Dawn Mooney explores the topic with Dr. Rodney Rhode, Professor and Chair, Clinical Laboratory Sciences Program for Texas State University and Mark Hodgson, Vice President, Health Care, UMF PerfectCLEAN.
They discuss what biofilm is, how it spreads, the difference between wet and dry biofilm, how it contaminates surfaces and how biofilm affects those in its path. You will also learn how to kill BIOFILM and prevent BIOFILM from spreading on surfaces using EPA registered disinfectant products with kill claims against BIOFILM.
If you don’t have time to listen to the podcast in one sitting – LaundryLedger will be publishing the transcript in two parts. Should you begin listening and decide to read along, you will find timestamps on the transcript below so you can easily follow along or pick up where you left off.
Dealing With Biofilm Transcript – Part One
[00:00:03] Michelle Dawn Mooney
Hello and welcome to Clean Matters, a podcast brought to you by PerfectCLEAN. I’m your host, Michelle Dawn Mooney, and today we’re talking about biofilm, the hidden threat lurking in your drains. It’s not pretty, but it is something we definitely need to talk about. What do patient rooms, guest rooms, and classrooms have in common? Well, it’s a sink. And every sink has a drain in which biofilm is lurking. So today I have two fabulous guests to talk about the topic at hand. Doctor Rodney Rohde is professor and chair, Clinical Laboratory Sciences Program for Texas State University, and Mark Hodgson is Vice President, Health Care, UMF PerfectCLEAN. Thank you both for being with me today.
[00:00:44] Dr. Rodney E. Rohde
Thank you so much, Michelle. It’s great to be here.
[00:00:47] Mark Hodgson
Pleasure to be back with you, Michelle.
[00:00:48] Michelle Dawn Mooney
Looking forward to our conversation. Before we dive in, can I have you each give a brief bio for our audience, please?
[00:00:54] Dr. Rodney E. Rohde
Sure. As Michelle mentioned, I’m at Texas State University. I’ve been in academia for about 21 years now. Prior to that, I spent a decade in public health at the Texas Department of Health and CDC as a visiting scientist. And really, the primary research area that I’m involved in is antibiotic resistance, antimicrobial resistance at the intersection of biofilms. So, this is kind of right in my wheelhouse. I’ve been working with this for about 10 or 15 years now.
[00:01:20] Mark Hodgson
And I am a chemist who has spent most of his career working with, developing and evaluating disinfectants, initially with such wondrous things as Legionella bacteria and Legionnaires disease. And obviously that involves a great deal of biofilm and biofilm studies. Prior to that, working extensively in the field of infection prevention and using my knowledge of disinfection to help eliminate fomites as a source of infection.
[00:01:53] Michelle Dawn Mooney
So we are ready for this conversation. And as I said in the beginning, it’s not pretty. It’s not necessarily something we want to talk about. It’s a little scary, but we need to. And the good thing is there are some solutions to what we are about to present to you. So Doctor Rohde, let’s start off with this. What is biofilm? Why is it an issue in health care?
[00:02:13] Dr. Rodney E. Rohde
Yes, thanks for the question. It’s a great place to start just trying to understand what a biofilm is. Most people, even if you’re not a scientist, have seen a biofilm. They are typically kind of slimy. You might have seen them on a rock in a stream. It’s also what’s on your teeth. It’s plaque. It can end up in many places that’s either microscopic or even macroscopic. So sometimes you can actually see these things with your eyes. Really, what they are, they’re living in a sense, about 80% of different types of bacteria and other agents like fungi and viruses and other things can live within this matrix. And that’s really what a biofilm is. Kind of think of a big, thick, sugary matrix. It’s often called an extracellular polymeric substance matrix, or EPS. It’s just a really slimy, jelly like substance. And anything from, one to multiple types of organisms can live within that community. And I sometimes describe it to the public kind of like a – it’s almost like a hotel that’s full of different pathogens just living in this place. And they end up in many places, of course, like drains that we’re going to talk about. They can end up on medical devices. They can end up on surfaces both wet and dry. And we’re going to get into that today a little bit.
But if you’re thinking about healthcare and you’re thinking about how important it is for something to be sterile, this is a problem, right? So, it’s giving bacteria, it’s giving pathogens almost an advantage in many ways because they are very resistant to disinfectants. It also makes them resistant to disinfectants, antibiotics and other antimicrobials. And so really when you look at the percentages in healthcare, anywhere from 65% or higher of many microbial infections, including chronic infections, come from these biofilm related types of problems. And so it just makes it problematic and more difficult to deal with when you talk about healthcare associated infections.
[00:04:15] Michelle Dawn Mooney
And I guess it’s not, you know, the biofilm itself that is the scary part here. But what is in the biofilm, as you said, because we have some scary things living in the biofilm. So, let me ask you this, what type of organisms are found in biofilm and are they dangerous? If so, how dangerous?
[00:04:36] Dr. Rodney E. Rohde
So great question. The types of organisms that you find in a typical biofilm are primarily bacterial. So again, I’m going to give you some names. You may or not be aware of these. But things like Pseudomonas really nasty genus of bacteria that shows up quite often, E. coli, and a lot of different Staphylococcus species. So, if you’ve ever heard of a staph infection, that might be kind of the generic staff species, or it might be from a methicillin resistant staph aureus. So, you get these bugs that are already resistant to antibiotic therapy. Different viruses, Candida auris, which is kind of a really emerging fungal organism right now across the country and just many others, it’s really a hodgepodge, but those are probably some of the more primary types that you will see in these types of biofilm matrix.
[00:05:30] Michelle Dawn Mooney
And, Mark, we want to bring you in here because this is kind of the key part of this conversation today. What does biofilm have to do with drains.
[00:05:39] Mark Hodgson
So the one element that is required for all bacterial growth or microbial growth is moisture. Unfortunately, the drain line in your sink is a beautiful way of collecting water and there is water resident in the P-trap. That’s how it works. So you have stagnant water, essentially. You have a surface on which the biofilm can attach itself. And then unfortunately, we have people who have a bad habit of pouring nutrient material down the drain. So, if you decide to tip your can of soda, if you decide to tip your half-drunk cup of coffee, unfortunately, all you’re doing is feeding the bugs. And what we have seen is that the biofilm is so pronounced in P-traps that it actually grows at a rate of up to almost an inch a day which means that instead of staying in the P-trap, unfortunately it tends to come back out of the P-trap. Doesn’t often grow out of the P-trap, but every time you turn on the faucet, water backflows out of the trap into the sink, and depending on how much force the water hits your drain with, you can get an aerosol generated that’ll transmit about a meter to a meter and a half from the sink containing the bacteria that were previously in the biofilm in your P-trap.
[00:07:19] Michelle Dawn Mooney
Oh, Mark, I, I don’t even know. I don’t even have words, first of all. But I think of that old movie, the Blob of just it’s growing and growing and growing. And, I mean, we all know nobody likes to clean the bathroom and have to do all that, but when you hear what is growing inside and thinking about what you’re saying, half a cup of coffee, I’m like, I think I just did that today. So clearly, we have some issues here that need to be addressed. So how can something in a drain line be at risk? This is really important for patients in a hospital room because we think about okay, it’s one thing we’re at home. But when you think about health care, you’re there to get healthy to get well so you don’t have to be there. So how does that play out?
[00:08:03] Mark Hodgson
We mentioned the potential to create an aerosol. That’s certainly one way where little droplets of water transmit through the air. Now occasionally they’re inhaled, but more normally all that happens is they land on a surface and they remain there. The organism remains viable. The health care workers hand touches that surface. And then touches the patient. But bear in mind, in health care, many of these sinks are actually used as part of the hand hygiene hand washing process. So, we always want our health care workers washing their hands before contact with the patient. Sometimes you use alcohol or hand rubs, but there are some pathogens that the alcohol hand rubs just don’t work for. And for those things like Clostridioides difficile, like norovirus, we recommend washing your hands with soap and water. And the idea isn’t that the soap is going to kill those pathogens, it’s that the soap and water will rinse them off your skin. But unfortunately, of course, when they rinsed off the skin, they end up in the drain and in the P-trap. And though Clostridioides, for instance, does not create a biofilm itself, it will quite happily colonize a biofilm that is created by another organism. So those are the sort of things that we have to deal with. We are literally washing our hands to get rid of pathogen, and at the same time we’re aerosolizing pathogen into the air, some of which can land back on our hands, some of which will land on surfaces. And then we have hand contact with surfaces, hand contact with the patient and potentially infection.
[00:09:46] Michelle Dawn Mooney
Doctor Rohde, what is the difference between biofilms that develop in drains and then those that develop on surfaces?
[00:09:55] Dr. Rodney E. Rohde
Yes that’s a really important distinction. I know this might be getting into the weeds a little bit for the general public, but what Mark says is so critically important, because that drain is typically in any place that’s hydrated or wet, is typically when you’re going to be talking about that type of wet biofilm that that kind of makes sense, right? You would think it needs to be hydrated and has some moisture, and it has the ability to maybe gain nutrients and so forth, but just as dangerous. And more recently research is showing this is sometimes a more dangerous issue with dry biofilms. And so dry biofilms are typically just what you might think they are. They’re devoid of moisture. They can form on surfaces from high use areas like crib rails, like in a child’s pediatric ICU to a bed rails to devices, medical devices to countertops. Just about anywhere that doesn’t have a lot of moisture is where you see these dry biofilms. And unfortunately, and this is going to come up a couple of times in our talk, dry biofilms are showing even more of a problem with resistance to some of these disinfectants and other things. In fact, you know, a lot of research shows that you almost have to mechanically remove these dry biofilms because they’re so adhered to the surface and so difficult to remove. And, you know, just to kind of throw this out there, you were mentioning Michelle how this kind of, you know, kind of catches you off guard when you think about this. But health care associated infections are real, and they’ve been a growing problem for over a decade or more now. Antimicrobial resistance and biofilms just amplify this problem because again, these biofilms are so problematic once they form and they become mature.
[00:11:55] Dr. Rodney E. Rohde
I want you to think about, it’s not just the disinfectant that can’t get into the inner part of that biofilm to kill the bug if it’s in your body, like if it’s adhering to a prosthetic, a knee, a screw, devices in your feet, things like that. Antibiotics can’t penetrate that as well. So, some people unfortunately end up having recurrent infections because the antibiotic, if you can imagine this as a surface and a little bit of biofilm, it will kill the topical parts because it can kind of get to that. But internal to that, it’s almost like trench warfare. You can’t get down into those micro communities. And then that nasty, biofilm will seed. They’re called persister cells, and they’ll literally break loose and they’ll go create another, micro biofilm somewhere else. So, it’s just, I mean, it’s tied to UTIs because of catheters. It’s tied to IVs. So, it is a huge problem of beyond drains and drains are a big problem. And that’s what we’re here to talk about today. But it is a global problem within the healthcare setting.
[00:13:00] Michelle Dawn Mooney
Yes, and I guess really the key here is prevention. You know, we’re talking about you know, Mark, you said how if it’s in the drain it doesn’t necessarily stay in the drain. And it can get on those hard surfaces. And then you know, we heard from you Rodney, about once they are on those hard surfaces, how hard it is. So if we can kind of nip things in the bud the best we can, then all the better. So, Mark, are there any guidelines for preventing wet biofilm in drains and if so, can you please walk us through those?
[00:13:30] Mark Hodgson
Yes. SHEA, in combination with the IDSA and APIC, recently published a new guideline on hand hygiene, and they addressed this very matter within that guideline. And what they said is that you should consider on a routine basis, disinfecting drain lines, disinfecting using a biocidal product that has passed the EPA registration for biofilms. So the EPA will now allow you to test and register disinfecting products to show that there is some degree of efficacy against bacteria in biofilms. And the recommendation is that you use one of those registered products to kill what is in the drain. There’s a couple of little wrinkles that kind of add to the fun. And the first one is that an awful lot of modern disinfectants have a very low pH. Ph of 2 or 3. Unfortunately, a different department within the EPA actually does not allow you to put anything with a pH of five or less into the drain, so what is unfortunately already a fairly limited range of available products, you eliminate over 60% of the registered products that are effective against biofilm. So that’s the first thing. That’s that requirement that didn’t make it into the standard. They just said biofilm efficacy. So, make sure it’s an EPA registered product and make sure it has kill claims against biofilm and works against bacteria in biofilm.
[00:15:18] Mark Hodgson
And make sure that your product is neutral pH. The other thing that has come up recently, and we’ve been dealing with a couple of outbreaks associated with drain lines in California, where the CDC has been involved, and the CDC is now requiring that the disinfectant is applied using a foam or in the form of a foam to make sure that you get the required contact time, which could be 4 to 5 minutes. There are a couple of other things. I mean, the first thing is stop people pouring things like sugary drinks down drain lines. Also, stop people putting medication into sink drains. We’ve seen people, you know, empty syringes of antibiotic in the drain line. So don’t dispose of antibiotics into the drain. Don’t dispose of any other medications into the drain. Make sure that, you know, your staff understands that it is best to wash, not pour the water directly into the drain line from the faucet. Reduce the pressure on the faucet. Reduce the aerosol production. There are some other products thrown in there as well, but the action that the CDC and SHEA/APIC/IDSA are recommending right now is, use a product that has EPA registered kill claims against biofilm applied in the form of a foam.
[00:16:43] Michelle Dawn Mooney
So, Mark, you mentioned the new guidelines, even if they have a few wrinkles. So how will these new guidelines impact health care facilities.
[00:16:51] Mark Hodgson
The first thing that the infection control manager is going to have to do is review the chemistry they’re using to disinfect. There are a very limited number of products on the market that have passed the EPA biofilm efficacy test. So make sure the product you’re using is one of those. Make sure that it is a product with a pH at least six. But 6 to 7 is ideal. And make sure it’s applied in the form of a foam. Those are the absolute basics at this stage. Work with your chemical supplier to get a product with that profile. The foam is important because it’s a surfactant and surfactant helps the biocide penetrate the biofilm. So it helps to break down the biofilm and get the disinfectant really into the microorganism that we’re targeting.
[00:17:59] Michelle Dawn Mooney
We just heard Mark talk about the different methods used to kill the organisms and the bad bacteria and biofilms. But, Doctor Rohde, are different strategies required to address wet biofilm, such as those found in drains and on dry surface biofilms.
[00:18:17] Dr. Rodney E. Rohde
I mean, Mark, you know, as a chemist, I really addressed that in a great way as a microbiologist and IP, that’s really my specialization. I see the biggest impact and the strategies, they’re really what Mark kind of said. But just to reiterate, education is going to be really critical for healthcare facilities going forward. And really I’ll throw it in community facilities because remember, while we’re focused on healthcare and we’re talking about drains, you could be talking about a dialysis center. You could be talking about a clinic. You could be talking about a free clinic. I mean, these things cross all sectors of society. So everyone needs to be educated. And we’re not all chemists like Mark, but you need some way to scientifically communicate. This is really critical. And in so many places in our country right now and in the world. Normal people, can they understand what they need to do? Um, including physicians, nurses and laboratorians. Not everybody is going to be an expert with disinfection. And so everyone needs to be brought up to speed on these things about pH, EPA regulation, you know, picking the right bullet for the right enemy is going to be really critical here. And then when you think about what he was talking about, I mean, for wet biofilm and drains and those types of biofilms, the movement is towards foam.
[00:19:39] Dr. Rodney E. Rohde
It is towards longer contact with those agents. It tends to be really high levels of Pseudomonas and E. coli and some of these other bugs that we’ve been talking about. And so you really want to pick the right agent in that foam to be doing its work. Dry biofilms offer a little bit more of a challenge at times, because you might actually have to find a way to disengage with some type of mechanical wiping or, or other mechanical destruction, if you will, if you don’t want to ruin the surface of everything, but you might have to find a way to kind of, detach that biofilm a little bit before you treat it with the chemical and the proper chemical. So that’s really important. And, you know, one of the things many of us are saying now in the industry is, if you are not disinfecting for the biofilm, then you’re really not disinfecting at all. Or if you are, it’s for a short, short period of time. So, you really need to think about that as you’re planning your chemical use and how you’re going to go about it.
NOTE: PerfectCLEAN’s Klorese is an EPA registered chemistry with kill claims against bacteria in biofilm.