Advice: Keep your hands clean around keypads, common surfaces
Amber Smith: Upstate Medical University in Syracuse, New York, invites you to be The Informed Patient, with the podcast that features experts from Central New York's only academic medical center. I'm your host, Amber Smith.
Have you ever wondered about how many germs live on surfaces like countertops, shopping cart handles, TV remote controls?
My guest today took a scientific look at the presence of pathogens on ATM machines. Dr. Joe Domachowske is a professor of pediatrics and also of microbiology and immunology, and he specializes in pediatric infectious disease.
Welcome back to "The Informed Patient," Dr. Domachowske.
Joe Domachowske, MD: Thanks very much.
Host Amber Smith: Where did the idea come from to examine ATM machine keypads for germs?
Joe Domachowske, MD: It's not unusual for medical students or other trainees to come to me and say, "Do you have a project that I can help out with?"
This was one of those projects that I had in the back of my mind for a couple years, even before COVID, and I thought, we have the machinery now to do this instrumentation, and we should really go for it. So the collection of students and trainees got together and made a plan, and that's how it all happened.
Host Amber Smith: What did you think you might find?
Joe Domachowske, MD: I was very skeptical, mostly because we started in January of last year, and we wanted to go a full calendar year. And of course it's not that long ago that all of us remember that that was sort of the peak of the Omicron wave coming through Central New York of COVID.
And so, given how careful everyone was being about cleaning and disinfecting and sanitizing, I really thought we'd be hard pressed to find a lot. But I figured we'd find something.
Host Amber Smith: Interesting. So how did you go about collecting samples?
Joe Domachowske, MD: The students and the other trainees got together and made a schedule of sorts, and they would be assigned certain days of the week to go to the ATMs and do the swabs.
They would take the swabs, and they would wet them with the transport media for the pathogens, for the organisms, and just have them damp, and then they would just rub it across the keypad of the ATM, put it back into the tube containing the rest of the solution, and then they would bring it back to the lab, and we'd do the PCR testing, the molecular testing, on the sample.
Host Amber Smith: So, was this more than one ATM machine, and where was it located? Indoors or out?
Joe Domachowske, MD: This was an indoor ATM machine that was a convenient location for us to access. The bank itself asked us to not disclose where it was, because we could do this anywhere and probably find the same thing, but they don't want to be identified specifically.
Host Amber Smith: Well, let me ask you a little bit more about, you said PCR. Can you explain the difference between traditional culture techniques and the molecular type of testing that you did and the relevance of using the molecular test for this study?
Joe Domachowske, MD: Molecular testing is done much more commonly now, even for human diagnostic testing.
For example, COVID PCR from a nasal swab, that's PCR, that's a molecular test. It's not a specific test that takes the sample from the person and tries to culture the virus itself in the laboratory.
And the reasons that things have swung toward molecular testing include that it's much more efficient. It's much more sensitive because what we're looking for with molecular testing is fragments, or pieces, of the germs' DNA or genetics in general. We can find even one copy of a piece of DNA or RNA that's been pretty much chopped up, but we amplify it artificially with these instruments in the laboratory.
If we're looking for culture, things get really complicated, especially with trying to do cultures of viruses. Every virus prefers a different type of cell to replicate in and get growing, so we'd have to have all sorts of different cell types. These are cancer cells that generally support different viruses to grow. They've been used in classic virology for a long time, but then some also like the cells to be supplemented with other types of very expensive supplements, essentially. And so we'd have to design a study that was really extremely expensive and time consuming to pick up all of the possible viruses and bacteria that we were looking for.
Host Amber Smith: If this molecular testing gives you, like, remnants of the pathogens or whatever, say you go in, and you take a sample at noon, are you looking at all of the germs that joined that ATM machine in the last 10 hours or last 12 hours, or how far back would it go?
Joe Domachowske, MD: Well, theoretically it would go back really as far as the detection of those genetic fragments could exist. That really goes back to the previous time there was really pretty rough sanitization of the instrument, or the "fomite," itself. Bleach, in particular, is really good at degrading RNA and DNA and getting rid of it. And we were at a period of time when that was being done, extremely carefully, on a regular basis.
And so I was wondering, are we going to really find much? And we did, as you know.
Host Amber Smith: Well, in the 12-month period that you studied, January 2022 to 2023, how many samples were collected?
Joe Domachowske, MD: We collected 234 samples from the same ATM keypad. And it was collecting them over the course of the year so that we could look over the full year, not just during cold and flu season, because one of the limitations of similar types of studies looking at different fomites were that they were only done during the outbreak of influenza or during a wave of COVID, for example.
And so they were sort of designed specifically to find a certain pathogen based on what was going on in the community, but we wanted to do it year-round, for a full calendar year. Of those 234 swabs that were taken, 36 of them, about 15%, were positive for either a bacterium or one of several different viruses.
Host Amber Smith: What were the most prevalent germs or viruses or bacteria that you found?
Joe Domachowske, MD: Well, not unexpectedly, the single most commonly detected pathogen was SARS-CoV-2, which is the agent of COVID-19. Nine of our positive samples were that agent itself, but it's not well appreciated that there are several other coronaviruses that are common causes of just mild upper respiratory infections, like a common cold. We found five of those, four of one kind and one of another. So as a group, that was the most common pathogen group that we detected.
The second biggest group detected were the adenoviruses. These viruses predominantly cause respiratory illnesses, but in young children, they can cause prolonged high fevers without much in the way of other symptoms.
They're very, very common, and they're also very stable in the environment because a characteristic of their virology is they don't have this envelope, sort of, around them. They have this sturdy "capsid" (a protein shell) that's kind of hard to get rid of. They're fairly stubborn in the environment, so it wasn't a big surprise. We found 13 of those.
And then the biggest surprise was we had five positive molecular tests, which were backed up with cultures. So all five of them also grew in culture for a bacterium called Bordetella parapertussis. This is a cousin of the bacterium that causes whooping cough. And it can cause a nasty cough illness in anyone at any age. We don't have a vaccine for it. But that was a surprise. It hasn't been described before from a fomite, so we were interested in that finding. And we did have a couple RSVs (respiratory syncytial viruses) that we picked up, and then a smattering of one or two of several other common viruses that cause respiratory illnesses.
Host Amber Smith: The word "Bordetella": I hear that when I go to the veterinarian's office. Is that the same disease that dogs might get when they're put in, like, doggy day care with other dogs?
Joe Domachowske, MD: Very close. Bordetella bronchiceptica is the cause of kennel cough, which is a veterinary pathogen infecting largely the dogs.
We even have a vaccine that's given to dogs to prevent it because it can cause such serious illness in the canines. Bordetella parapertussis is a human pathogen, but it's sort of a "pathogen lite" compared to its more famous cousin, Bordetella pertussis, which is the cause of whooping cough.
Amber Smith: This is Upstate's The Informed Patient" podcast. I'm your host, Amber Smith.
I'm talking with Dr. Joe Domachowske about a study he oversaw looking at germs on ATM machines.
Host Amber Smith: Now, I learned a new word: "fomite." So that's something that's likely to carry infection? Is that how you would define it?
Joe Domachowske, MD: Any fomite certainly could carry infection, but fomites in general are any inanimate objects that are found in the environment, so doorknobs, ATM keypads, books, pencils, bedding, clothing, really anything that's inanimate that potentially could get exposed to or contaminated with human secretions of any kind. And if those secretions have pathogens or germs on them, they can kind of hang out for a while and someone else comes along and is unaware, happens to touch it and then touch their eyes or their nose or their mouth, they could potentially inoculate themselves.
Host Amber Smith: Do you think there are people in our community who were exposed to germs or got sick from those germs after using the ATM machine after someone who was infected?
Joe Domachowske, MD: This is the controversial part of the description of the science that we laid out.
And that's because it's hard to prove something like that. But the part of our study that differed from most other research done on fomites is that we backed up every single positive PCR molecular test with culture.We did not do cultures on everything, because it would've been very time consuming and probably too expensive to afford.
But any positives that we had, we picked the culture techniques that would optimize recovery of that particular agent, and we were able to recover 75% of those 36 positives that we had. So, this suggests to me that there's replication-competent, viable pathogen on many of these swabs, and it wasn't just remnants of DNA or RNA that was already rendered non-infectious, either through drying or through alcohol wipes or whatever they're doing to sort of sanitize the keypads.
Host Amber Smith: Assuming that some fomite or some kitchen counter or ATM surface is not sanitized, how easy is it for germs from a cough or a sneeze to live there and then transfer onto the hands of another person or into the eyes or mouth? Is it an easy task for that pathogen to live?
Joe Domachowske, MD: It's not. It's actually quite stressful, and most agents won't survive in the environment at those temperatures lower than body temperature in a replication-capable manner for more than a couple of hours, with some exceptions. And it also depends on how much, let's call it "juice," comes with it. If it's a cough or a sneeze from really microscopic aerosols, then it's probably not going to hang around long. They'll evaporate and dry, and these agents do not like to be dry. They die very quickly.
But if the contamination happens where there's some mucus involved, or it's from the hands after touching the nose or the mouth or the eyes, and they get contaminated with some mucus and some body fluid, even though you can't see it anymore, if it's still there, can sort of protect those agents from environmental factors that will inactivate it.
So not more than a few hours for most of these things, but something like adenovirus can persist on surfaces even up to two or three days.
Host Amber Smith: I'm assuming we know this because there's other similar studies that have been done about pathogens living on inanimate objects.
Is that right?
Joe Domachowske, MD: That's true. And most of that work has been done in hospital settings or long-term care facility settings, some of it artificially, where countertops are exposed to known amounts of certain pathogens, and then recovery at different time periods after that are attempted.
But sometimes the studies involve similar methods that we used, where the countertops or the higher-risk, frequently touched areas are checked for these agents. And if they are found to be present by molecular methods, there may be an attempt to see if it's viable agents that are there, and this really has changed the way we disinfect things in places like hospitals, where there is very, very aggressive disinfection, especially when something like COVID is going through the community. I kind of read through some of the COVID experiments where in hospital settings, scientists were looking for SARS-COV-2 in patients' rooms or nearby their rooms.
And when they could detect it by molecular methods, but they could not get it to grow in culture, they argued that we don't have to worry about fomites transmitting SARS-CoV-2, but the part that I think they missed was that it's an artificial setting because it's so intensely cleaned all the time, repeatedly, and so there may be residual bleach or other sanitizing agents on the counter.
And yeah, we can detect some of the RNA from the COVID that the patient has and has contaminated their
So, that's very different than if we talk about an elementary school countertop next to a sink or an elementary school bathroom or ATM machine that's just getting a lot of traffic all day long without being cleaned every time, in between every use.
Host Amber Smith: Well, what do you think is the takeaway from your study?
Joe Domachowske, MD: I think we have to be careful about fomite transmission in our community, not just for SARS-CoV-2. That was obviously the top one on our list, but we did this study during the Omicron surge, so just by definition, we'd expect it to be the most common one we detected.
It was the most common thing going around in the general community in adults at the time. So we have to be careful, and I looked to some of these studies done in elementary schools looking for influenza or looking for pathogens that intend to target the young children even more, like RSV, as far as that age group goes, and we would find it.
And we just have to be careful about maintaining some level of care in sanitizing these frequently used areas, especially if multiple people are going back and forth and touching it on a regular basis during the day. And that's common sense.
And to me, that's just like "wash your hands," right, as much as you can. but with the hospital-based studies coming out about COVID-19 not being able to be grown from these swabs that detect the RNA, there's now this cluster of scientists that think we're overemphasizing the risk of fomites, and I think that they're probably overstating the results that they found, forgetting the type of environment that they were trying to culture the agent from.
Host Amber Smith: Well, before we wrap up, I'd like to talk about the sensible precautions we can take to reduce the chance, aside from washing our hands, are there best practices for using an ATM? If I go in there, and I know this is a fomite, and I want to keep myself safe, what should I do?
Joe Domachowske, MD: Well, as far as I'm aware, there are not very many touch-free ATMs around. You still have to touch it. There's not the voice-activated kinds of things that we've switched to for other related kinds of tasks. But just be careful and wash your hands or use hand sanitizer before, do your thing, and then (use hand sanitizer again) after. You could even carry some gloves and put the gloves on and press the buttons with your gloved hand.
I remember coming back to work at the hospital when things were starting to open back up again (during the pandemic), and we were starting to see more and more sick patients in the hospital, just in general, after a long period of time where we didn't see a lot of sick kids, and just walking in and going into the elevator thinking, "OK, how do I do this without the possibility of touching something and not getting to clean my hands right away?" And I would just cover my hand with my sleeve of my coat and hit the button that way. So there there are ways to do it, but I think just having one of those tiny little pocket hand sanitizers handy is always a good idea.
Host Amber Smith: So, I think a lot of people were introduced to hand sanitizers during the pandemic, but obviously they work against things other than the coronavirus.
Joe Domachowske, MD: Yes, absolutely. And they're highly effective against most of those agents, but not all infecting agents are inactivated by alcohols or related substances. They really do have to have that envelope part if they're a virus in order to be inactivated. Those adenoviruses, they're so sturdy, they will resist standard concentrations of alcohol.
They are inactivated by bleach, but not by other cleaning agents that we typically would use.
Host Amber Smith: So, I'm not going to be washing my hands in bleach. Does soap and water do the job or no?
Joe Domachowske, MD: Absolutely. Soap and water is great for absolutely all of it. It not only eliminates most of the pathogens from your hands or bacteria from your hands, but even for the ones that can persist in the environment because they're not inactivated, just the physical action of washing and rinsing your hands off with the water reduces the amount that's on your hands already.
Host Amber Smith: That's really good to know. Dr. Domachowske, thanks so much for making time to tell us about your work.
Joe Domachowske, MD: It's my pleasure. Thanks.
Amber Smith: My guest has been Upstate professor of pediatrics and microbiology and immunology Dr. Joe Domachowske.
"The Informed Patient" is a podcast covering health, science and medicine, brought to you by Upstate Medical University in Syracuse, New York, and produced by Jim Howe.
Find our archive of previous episodes at upstate.edu/informed.
This is your host, Amber Smith, thanking you for listening.