Bug of the Month helps educate readers about existing and emerging pathogens of clinical importance in healthcare facilities today. Each column explores the Bug of the Month's etiology, the infections it can cause, the modes of transmission, and ways to fight its spread. The pathogen profiles will span bacterial, viral, fungal and parasitic species. We encourage you to use Bug of the Month as a teaching tool to help educate healthcare personnel and start a dialogue about microbiology-related imperatives.

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Bug of the Month helps educate readers about existing and emerging pathogens of clinical importance in healthcare facilities today.

December 2019 Bug of the Month

The US Centers for Disease Control and Prevention (CDC) recently released an update to the 1998 guidelines for occupational health infection prevention. This new edition provides guidance in many areas of occupational health, including leadership and management, communication, assessment, risk reduction, education, and immunizations. The intent of these guidelines is to provide recommendations to leadership and staff of occupational health (OH) programs in the services they provide that are related to infection prevention (IP) activities that reduce the risk of disease transmission among health care providers (HCP) and patients. As many infection preventionists may hold dual roles in occupational health, or are considered, at minimum, subject matter experts and strong collaborators with occupational health programs, these updates will be a valuable resource for infection preventionists. 

The leadership structure of OH programs can vary depending on the healthcare settings. It is imperative that the staff assigned to these roles understand the responsibilities associated with providing the OH program. If staff are in multi-purpose roles, the resources may be focused on meeting regulatory requirements and the other aspects of the program may not receive as much attention. Organizations can help support OH programs by providing dedicated staff and encouraging certification. 

One of the main areas under this section is performance measurement and quality improvement. In order to validate the effectiveness of the OH program, it is key to be able to assess data regarding specific outcomes such as HCP exposures, HCP follow up for testing, HCP conversions after exposure, tuberculosis screening and fit testing completion, vaccine compliance, and many others. Unfortunately, OH programs can be under-resourced in the areas of data analytics, and in order to be able to extract this information in a rapid and accurate method can be a challenge. By investing in the technological infrastructure around OH, time spent on manual data collection can be geared toward more clinical and quality improvement efforts. 

Emergency preparedness is another area where OH capacity can be strengthened. Overall healthcare preparedness for a biohazardous event, such as pandemic flu or emerging infectious diseases, is lacking across the nation. Infection preventionists are the subject matter experts for those situations, however OH programs will be integral for the HCP follow-up and support if such events were to occur. Occupational health programs should be included in any organization’s plans and exercises involving biohazardous events. 

Communication and collaboration within OH programs and across the organization can improve the safety of HCP and the effectiveness of the program. OH staff need to be at the table for decisions made with ordering of new supplies such as needles, sharps, disposal containers, and personal protective equipment. Also, communication can be a challenge when the OH program staff are dispersed across an organization. Infection prevention often is a liaison between OH programs and clinical staff and must reinforce the need for effective communication across the programs. 

Regular risk assessments for OH programs are essential to ensure that the needs of the HCP are being met and can guide the focus areas for improvement for the program. If OH does not have the capacity for maintaining its own regular risk assessments, collaboration with IP can ensure that at least annually the OH aspects associated with IP can be included in the annual IP risk assessment that is performed. Risk assessments should be done any time there is a change in services provided or in the work environment that may change the way that care is being provided by the HCPs. There are many templates available for risk assessments, and not all have to be a large undertaking, but at minimum there should be documentation that the OH program has reviewed this new service or change, has evaluated whether there is increased risk for transmission of infection and, if necessary, has outlined steps that can be taken to mitigate that risk. 

Medical evaluations are the largest component of clinical duties for OH programs. Of particular concern for the IP are the vaccination and immunity verification pre-employment, assessment for respirator testing, TB screening, post-exposure monitoring and testing, and other routine or special cause evaluations. Pre-employment screening is key to ensuring staff can be safely placed into the workforce. However, due to pressures to place staff quickly in order to provide continuity of services, it may be difficult to complete screenings for all new hires in the most optimal method. In this case, IP and OH need to collaborate to reinforce the importance of a thorough pre-employment screening, as well as meet with human resources in the onboarding process to advocate for the appropriate time considerations for this step. 

Education on OH policies and procedures is done for HCPs upon new hire, in annual refresher trainings and as needed based on situation. Several topics are required education based on federal regulations, including blood borne pathogen training, respiratory protection standards, and PPE standards. Often OH and IP programs collaborate on this training. As with any staff education, it is important that the health literacy of the audience be assessed, and the information be presented in a way that is understandable and applicable to their work functions. 

Immunization programs have become increasingly important in the role of ensuring staff and patient safety. With the reemergence of vaccine-preventable diseases (VPD) and the requirements many organizations have for annual flu vaccination, these programs can be resource intensive. The role of IP in these programs is to provide guidance on the types of vaccination that should be required for HCPs based on job risks and work duties. Also, IP can help with the logistical planning of administration of annual flu vaccine campaigns. Along with the administration of the vaccines, equally important is the record management of staff vaccine history. Again, without a robust IT infrastructure, many OH programs rely on paper and manual methods for tracking vaccination status. This can be cumbersome and unreliable, especially in the case of an exposure to a VPD or for reporting purposes. IP also can assist with developing strategies to increase HCP uptake of vaccines. If there is a challenge in getting HCP to receive vaccines, an assessment can be performed to determine what barriers staff perceive with complying and efforts can be targeted to addressing those barriers. 

There are many challenges with the prompt and effective management of potential communicable disease exposures: staff may not report an exposure until many days after it has occurred; tracking down all staff who may have come in contact with a potential source and then making sure those staff are contacted and follow through with OH evaluations; making sure policies and procedures are in place to handle exposures on off hours when OH is not available; and enforcing workplace restrictions or sick leave for HCP who may be ill. Often the IP program is the first to alert OH that an exposure has occurred, and then both teams must work closely together to investigate and prevent further exposures. Hospital leadership is needed to support when staff are required to take work restrictions or to have staff come to OH for evaluation after an exposure has occurred. 

Occupational health and infection prevention programs work integrally to ensure the safety of staff, providers, and patients. Having a strong OH program will only enhance the capabilities of the IP program to be successful. Infection preventionists should understand the role of the OH program and all the ways it touches IP practices. The updated guidance from CDC provides an opportunity for OH and IP to review the recommendations, perform a joint gap assessment of the current state of the OH program, and develop strategies to implement, enhance, and strengthen the infection prevention services of the OH program. 

Exploring CDC Guideline Updates for Infection Control in Healthcare Personnel 

Nursing homes can present a challenge for infection prevention efforts when teams must balance resident quality of life with the need for measures such as room restrictions and use of personal protective equipment (PPE). 

These facilities are ripe for transmission of multidrug-resistant organisms (MDROs), but new evidence suggests use of traditional Contact Precautions may not be adequate. 

To fill the gap, the US Centers for Disease Control and Prevention (CDC) has recently unveiled a new approach called Enhanced Barrier Precautions (EBPs), which rank in between Standard and Contact Precautions, and “require gown and glove use for certain residents during specific high-contact resident care activities that have been found to increase risk for MDRO transmission,” according to the CDC. 

, Kara M. Jacobs Slifka, MD, MPH, and Nimalie D. Stone, MD, MS, both physicians with the Long-term Care Team in the Prevention and Response Branch within CDC Division of Healthcare Quality Promotion, provide an in-depth overview of EBPs and how to implement them. 

Why do multidrug-resistant organisms pose such a threat in nursing homes, in particular, as opposed to other healthcare facilities? 

Multidrug-resistant organisms (MDROs), especially those for which we have limited antibiotic treatment options, pose a threat in healthcare because they colonize individuals for prolonged periods of time, silently spread, and cause invasive infections with high morbidity and mortality. As healthcare delivery keeps shifting away from hospitals, nursing homes are providing more care to medically complex and frail individuals who are more vulnerable to the harms from MDROs. The combination of the long lengths of stay, exposures to indwelling medical devices and antibiotics, and the increased dependence of nursing home residents contribute to the spread and acquisition in this setting. 

ICT: What are some of the current gaps in infection prevention practices in nursing homes that need to be addressed?

The key to preventing spread of MDROs comes down to consistently following basic infection prevention and control practices during care at the bedside; however, health department and CDC teams have routinely found gaps in these practices during visits to nursing homes across the country. The most common infection prevention gaps involve hand hygiene, the use of personal protective equipment (PPE) and precautions, and cleaning and disinfection of environmental surfaces and shared equipment. The implementation of these practices depends on 3 things: 1) educating healthcare staff about when and how to perform these infection prevention practices, 2) ensuring adequate supplies are available at the point of use, such as resident rooms and care areas, and 3) monitoring and providing feedback on staff adherence to practices. The incorporation of these practices is critical during all aspects of resident care from physical therapy to wound care. As an example, during our visits, we commonly hear misconceptions about the use of alcohol-based hand rub (AHBR) such as ABHR not being as effective as soap and water, or that adding ABHR dispensers will reduce the “home-like environment” of the nursing home and have the potential to be cited during the survey process. However, ABHR is the preferred method of hand hygiene unless hands are visibly soiled or during a 

or norovirus outbreak, and increasing access to ABHR, such as inside and outside of resident rooms, increases staff adherence to hand hygiene. Performing hand hygiene audits is informative for providing feedback and determining the need for education or intervention. 

ICT: In nursing home facilities, why is it challenging to rely on the routine contact isolation precautions used in hospitals when there’s an outbreak of a multidrug-resistant organism? 

The main challenge with implementing Contact Precautions in the nursing home setting is the need to restrict residents to their room, especially when the reason for Contact Precautions is a multidrug-resistant organism (MDRO). Residents colonized with MDROs are often colonized for prolonged periods of times (ie, greater than 6 months) and typically have longer stays at the nursing home than in an acute care hospital. Limiting a resident’s movement and participation in the facility for extended lengths of time can impact rehabilitation, involvement in social activities, and negatively affect their well-being. For this reason, Contact Precautions are intended to be time-limited, while Enhanced Barrier Precautions can provide a more balanced and sustainable approach to MDRO prevention. 

ICT: What are Enhanced Barrier Precautions (EBPs) and how do they differ from standard and contact precautions?

Enhanced Barrier Precautions (EBP) expand the use of PPE beyond situations in which exposure to blood and body fluids is anticipated and recommends the use of gown and gloves during high-contact resident care activities that have been shown to provide opportunities for transfer of MDROs to staff hands and clothing. Enhanced Barrier Precautions falls on the spectrum in between Standard Precautions and Contact Precautions. Standard Precautions should be followed with all residents at all times, including residents for whom EBP or Transmission-Based Precautions are being used. EBP is more specific than Standard Precautions by requiring PPE use for high-contact resident-care activities, but less restrictive than Contact Precautions as PPE is not required for every room entry/activity and residents are not restricted to their rooms. 

ICT: What are some of the high-contact resident care activities where EBPs should be used?

High-contact resident care activities include: dressing, bathing/ showering, transferring, providing hygiene such as brushing teeth and combing hair, changing linens, changing briefs or assisting with toileting, device care or use (including: central line, urinary catheter, feeding tube, tracheostomy/ventilator, and wound care).

ICT: How can healthcare administrators ensure proper implementation of EBPs? 

Healthcare administrators can help by prioritizing infection prevention within their facility. This includes providing dedicated staff time to implement the infection prevention program. EBP will be a new concept for many nursing homes; staff, residents, and families will need to be educated. Administrators can also help by ensuring that staff have access to the supplies they need to follow recommended practices. Adherence to hand hygiene in a facility isn’t going to improve if staff don’t have access to alcohol-based hand rub at the point of care. Similarly, staff aren’t going to use PPE or clean and disinfect shared equipment after each use if they have to search the unit to find supplies. 

ICT: Anything else you would like to add about EBPs?

Using EBP to prevent the spread of MDROs helps facilities support resident safety and resident well-being but will require education of staff, residents, and families. CDC is developing additional materials to support implementation of EBP such as a list of Frequently Asked Questions. CDC recently presented a webinar introducing the need for and describing EBP, which is available online; has developed signage for EBP and Transmission-Based Precautions; and has released a comprehensive infection prevention training course for nursing homes. 

The key to preventing spread of MDROs comes down to consistently following basic infection prevention and control practices.

Enhanced Barrier Precautions:  A New Approach to Preventing the Spread of Multidrug-Resistant Organisms in Nursing Homes 

nfection prevention is commonly thought of as a set of processes and procedures to help reduce infections during medical care. Although this is certainly true, it is critical we remember the infection prevention programs and infection preventionists (IPs) that help educate, enforce, and drive change through these processes.

To say infection prevention is singular in focus would be a painfully inaccurate statement. Infection prevention and control (IPC) encompasses everything from disease surveillance (for both healthcare-associated infection but also communicable diseases), risk assessments related to construction within the healthcare facility, education, policy revision, device rounding, and more. Too often, though, we forget that IPC efforts by the IPs are heavily impacted in the face of outbreaks and exposures. Outbreaks in healthcare facilities, like those of drug-resistant organisms or respiratory viruses, can be devastating to patients and staff alike. In the face of exposures, like measles or tuberculosis, there is often little time to notify those exposed and ensure secondary cases do not occur. In either case, the daily work for IPs drastically changes to accommodate these emergency situations. 

As we head into flu and respiratory virus seasons, hospitals work to ensure staff are vaccinated and well-supplied with the necessary personal protective equipment (PPE). There have been several outbreaks over the years that have not only reinforced the importance of IPC programs and the IPs, but have also emphasized that hospitals can easily act as amplifiers for disease. To better understand how these 2 intersect, let’s discuss several outbreaks that have occurred within healthcare settings. 

Neonatal intensive care units (NICUs) are one of the most high-risk hospital units, as the patients are extremely vulnerable to disease and respiratory infections can be deadly. Unfortunately, respiratory viruses, like influenza and respiratory syncytial virus (RSV) can easily be transmitted through NICUs. Outbreaks, sadly, are more common than we’d like to admit and the seriousness of the situation is not lost on IPs. Often, exposure to RSV comes from family, staff, or the design of NICUs (commonly in a pinwheel formation), meaning that transmission from baby to baby is much easier. 

From the IP perspective, here’s how it usually happens: A first infant is tested and found to have RSV and then, regardless of the case being community-onset or healthcare-associated, the infant is placed in isolation and great care is taken to ensure there is no cross-contamination during care. Moreover, all children who were paired with that infant (ie, under the same nursing assignment and, thus, more likely to be exposed) are cohorted and monitored for signs/symptoms, with a nurse or team of nurses assigned only to them in order to reduce the chance of transmission beyond this cohort. Symptomatic infants and those exposed are monitored for 2 incubation periods to ensure transmission has truly halted. IPs work with NICU staff and visitors to discuss what this means, explain the time frame for monitoring, and emphasize the need for enhanced vigilance in hand hygiene and respiratory etiquette. Often, visitor restrictions are enacted (children under 12 years of age) and other enhanced infection prevention measures are utilized to help reduce transmission. 

Multidrug-resistant organisms are another adversary that IPs have to face frequently. Even the most prestigious hospitals, like the US National Institutes of Health Clinical Center, have faced challenges in outbreaks of resistant microbes. In 2011, the facility faced an outbreak of carbapenem-resistant 

that infected 18 patients, 11 of whom died as a result of the resistant infection. Ultimately, what they found was 3 transmissions from a single patient who was discharged 3 weeks prior to any of the new cases. The patient had a known history of colonization with the resistant pathogen and enhanced contact isolation precautions were deployed, but cases began to spring up 3 weeks after the patient’s discharge. 

In response, infection prevention efforts were enacted, including strict cohorting of colonized patients that minimized the sharing of patient equipment, care providers, and surveillance cultures. Moreover, monitoring compliance to isolation precautions was utilized, which required considerable IP efforts. Although the out- break did eventually halt after 2 months, it was a stark reminder of the ease at which resistant organisms can spread. 

A last example of the IP changes in the face of an outbreak is one that many of us would rather forget-the 2014 Dallas Ebola cluster. Without reiterating too many details most of us lived out in real-time, this outbreak was especially poignant in that it revealed 3 key aspects of infection prevention and outbreak response in healthcare. First, hospitals in the United States were not prepared for a large outbreak, let alone one involving a viral hemorrhagic fever. Second, infection prevention practices for Ebola were constantly evolving during this time, meaning that education and PPE purchasing was in a continuous state of change. Third, the lack of infection prevention preparedness and a poor response led to the 2 nosocomial cases that resulted in a lawsuit. 

The Dallas Ebola cases were not only significant for the particular Texas hospital, but for every single healthcare facility across the United States. A majority of Ebola preparedness efforts fell upon IPs, consuming roughly 80% of their time. 

Outbreaks of emerging infectious diseases that we do not commonly see in the United States require response efforts that must consider a whole new realm of potential avenues of transmission due to the advanced medical capabilities we have. This cluster of Ebola virus disease in Dallas was a huge lesson for US healthcare and biodefense, but also highlighted the role of IPC. 

In addition to responding to outbreaks, infection preventionists have to be able to stop their daily efforts and help guide communicable disease exposures when they inevitably occur in healthcare settings. With 36 million hospital admissions per year in the United States and roughly 18 million healthcare workers exposures, it’s not surprising that exposures would be a 

frequent source of frustration for IPs. A recent survey found that these exposures are time-consuming not only for IPs, but also nurses. Infection preventionists reported the most time-consuming outbreaks/exposures resulted from mumps/measles, tuberculosis, gastrointestinal viruses, and multidrug-resistant organisms. For an exposure to 

, lice or scabies, and influenza, there was a more than 60-minute workload increase for nurses. From a cost perspective, these exposures can be quite impactful on the healthcare facility. 

One such example would be hospital exposures related to measles. Since we have seen a growing number of cases and outbreaks in recent years, the threat of measles exposures following an infectious patient presenting in an emergency room or hospital is considerably higher. When exposures occur, infection preventionists must often perform chart reviews, compile lists of exposed contacts, establish preventive measures for future exposures, and also round on the units and notify staff/visitors. This becomes even more burdensome and laborious when it involves an airborne organism like measles or tuberculosis, as the list becomes inherently longer. Similar to outbreak situations, the IP must identify and work closely with staff to establish which patients were exposed and the potential incubation period that requires close observation and isolation. 

These examples have been limited to the infectious patient or healthcare worker, but IPs have also had to respond to situations involving contaminated medical devices. An outbreak of carbapenem-resistant Enterobacteriaceae (CRE) within the University of California, Los Angeles (UCLA) Medical Center is a prime example of how such outbreaks and exposures impact the IP workload and scope of practice. This particular outbreak of CRE was related to use of duodenoscopes that were later found to have a flawed design that led to a higher risk of contamination and disease transmission. This exposure is a particularly unique example of how IPs are expected not only to have a wide scope of practice, but also to work with various deparments and public health agencies to coordinate exposure lists and notifications. Whether it be a communicable disease like measles or pertussis, or a multidrug-resistant organism, infection preventionists carry a significant burden when it comes to exposures involving patients and healthcare workers. 

In the face of a growing Ebola virus disease outbreak in the Democratic Republic of the Congo and the ongoing threat of multidrug-resistant organisms on the home front, infection preventionists are constantly in a state of preparedness, ready to respond to outbreaks and exposures. In many ways, we are running from fire to fire hoping to put one out before the next begins. The spectrum of infection prevention work is not just limited to preventing healthcare-associated infection in patients, but also involves ensuring staff and visitors are safe from communicable disease while in the healthcare facility. Exposures and outbreaks alike test the very boundary of infection prevention and require IPs to be stead- fast, efficient, and effective in their practice. 

On High Alert: How Infection Prevention Changes in Outbreak and Exposure Situations 

Over the last few years, duodenoscopes have been associated with outbreaks of multidrug-resistant organisms such as carbapenem-resistant 

These scopes have shown a propensity for easing the transmission of multidrug-resistant organisms. There continues to be a strong infection control and regulatory focus on reprocessing to ensure patient safety. The flexible medical devices are used in endoscopic retrograde cholangiopancreatography (ERCP) procedures to help visualize and assess not only the small intestine, but also the pancreas and bile ducts. 

Because of the device’s intricate design, duodenoscopes are often more difficult to disinfect than other tools, such as endoscopes. The US Food and Drug Administration (FDA) even issued a recommendation over the summer for duodenoscope manufacturers and healthcare facilities alike to move towards scopes with disposable components, specifically the endcaps. 

“We recognize that a full transition away from conventional duodenoscopes to innovative models will take time and immediate transition is not possible for all healthcare facilities due to cost and market availability,” Jeff Shuren, MD, JD, director of the FDA’s Center for Devices and Radiological Health, said in a statement. “This is why we’re communicating with healthcare facilities now-so they can begin developing a transition plan to replace conventional duodenoscopes-and those facilities that are purchasing duodenoscopes with fixed endcaps can invest in the newer, innovative models.” 

In research presented recently at the American College of Gastroenterology’s Annual Scientific Meeting, investigators with Indiana University School of Medicine compared disinfection methods to determine whether reprocessing duodenoscopes with double high-level disinfection (DHLD) or chemical sterilization is more effective. 

The prospective study analyzed 2 methods of duodenoscope reprocessing between October 2017 and September 2018, randomly culturing the tools post-reprocessing for surveillance. The first DHLD method comprised complete manual cleaning followed by automated reprocessing, repeated for 2 total cycles. The second method involved liquid chemical sterilization. 

Investigators performed a total of 878 post-reprocessing surveillance cultures (453 in the DHLD group and 425 in the sterilization group). Out of all the samples collected, 17 (1.9%) were positive. Two cultures from both study groups grew high-concern organisms, but no multidrug-resistant organisms were detected. When comparing the 2 disinfection methods, there was no significant difference of positive cultures between DHLD (8 positive cultures, 1.8%) and chemical sterilization (9 positive cultures, 2.1%, p>0.05).

“DHLD and liquid chemical sterilization both resulted in a low rate of positive cultures, both for all organisms and for high-concern organisms, but neither process eliminated positive cultures from reprocessed duodenoscopes,” investigators concluded. “A liquid chemical sterilization protocol did not improve the growth of organisms on surveillance cultures compared to DHLD.” 

Disinfecting Duodenoscopes: Does the Method Make a Difference?

Healthcare environments are dirty. There’s no way of avoiding it – hospitals, urgent care facilities, and other medical centers are constantly battling microorganisms. Cleaning and disinfection are critical in these environments to help reduce the risk of transmission. Consider that roughly 1 in 1001 people carry methicillin-resistant 

(MRSA) while 1 in 3 carry drug-susceptible 

, are known to cause diseases in these settings and are often culprits in healthcare-associated infections. Effectively removing these organisms from the environment is critical for infection control efforts. While disinfecting wipes and sprays have been the go-to for decades, ultraviolet-A (UV-A) light exposure has been growing in popularity. While UV-A is a method for disinfecting surfaces and objects, it can’t sterilize products, but it can help reduce bio-burden in patient rooms, waiting areas, operating rooms, and other high-risk areas. Like many new technologies, UV-A disinfection is still finding its way into hospitals as staff become more comfortable with its infection control capabilities. 

A new study2 tested the efficacy of UV-A disinfection for decontamination against health care-associated pathogens on surfaces. The researchers used a ceiling light fixture for the UV-A source, testing its efficacy on killing microorganisms by assessing recovery on a version of the American Society for Testing Materials standard quantitative carrier disk test method. This disk includes a strain of MRSA, 

and 2 kinds of virus bacteriophages. The efficacy of the UV-A light was also evaluated for its capabilities of reducing contamination of 32 in-use portable pieces medical equipment. Doppler ultrasound machines, glucometers, wheelchairs, and workstations-on-wheels were some of the equipment tested by being placed 2 meters from the light source for 4 hours. 

Researchers found that these 4 hours yielded a significant reduction in pathogenic microorganisms from the medical equipment in use and mostly on the disks. There was a modest reduction in MRSA, 

spores were not reduced or minimally reduced after 24 hours of exposure to UV-A at 3 W/m2 (0-0.2 log10 CFU reduction),” the authors wrote. 

Prior to the use of the UV-A disinfection of the medical equipment, 37% yielded pathogenic microorganisms, while only 10% did after the disinfection, which was statistically significant. 

The authors note that these findings suggest the potential for UV-A disinfec- 

tion to aid in the reduction of pathogenic microorganisms that contribute to healthcare-associated infections. There should be a concern though for the health and safety of those exposed, which amplifies the importance of manufacturer guidance and proper protocols. Moreover, this component might increase the required cleaning time for certain areas, which should be considered prior to use. 

While the UV-A disinfecting light did provide a modest reduction in micro-organisms, the resilience of 

and the existing microbial burden should not be forgotten. UV-A light has shown promise in its capabilities to reduce microorganisms in healthcare environments; however, it cannot and should not be a substitute for the manual cleaning and disinfection that is required to remove biofilm and other hardier bioburden. 

UV Disinfection Tackles MRSA-What About C difficile? 

 Becky Smith, MD, medical director of infection prevention at Duke University Hospital, discusses a presentation she gave at IDWeek 2019 on a case of serial transmission of NDM-1 

Interview transcript (modified slightly for readability):

 We perform routine surveillance for carbapenemase-producing organisms, or CPO, at Duke Hospital just like many infection prevention programs do. In 2017, we noticed an uptick in seeing CPO within the hospital. This particular research came out of finding something called NDM-1, which is 1 of the various molecular mechanisms for carbapenemase-in this case, it's actually a metallo-beta-lactamase gene-within a germ that is considered to be a tier 2 organism per the CDC guidance. What that means is these are either multidrug-resistant pathogens with a novel resistance mechanism, or they are not yet endemic in the area. And so the state health department and CDC recommend enhanced containment efforts to really try to contain them or stop their spread because they aren't everywhere yet, so you have an opportunity to make a difference.

In 2017, we identified a patient in our hospital who had an NDM-1 Klebsiella pneumoniae. At the time, we engaged the health department as per the CDC guidance, and we reviewed the medical record to find out [whether] this patient [had] traveled to anywhere where there was endemic NMD-1 and/or where else had they been that they could have picked this up. And as part of that investigation, we found they hadn't really been anywhere typical; they had been to an outside hospital before they had come to us.

In response to this, we performed some point-prevalence surveys where we screened everybody else on the unit. We did 2 rounds of that and did not find any other patients with the organism, and we were very relieved so we sort of put it to rest. This investigation actually took place kind of in the midst of this uptick in seeing more carbapenemase-resistant organisms. We had already been in the process of trying to augment our approach to carbapenemase-producing germs in general, and what that meant at our hospital is, in addition to the normal surveillance and reaction, we wanted to be more proactive. We had an enhanced educational series for all types of healthcare workers, patients and families on what are these germs and why is it so important that we wash our hands and wear gowns and gloves and clean the environment. We also implemented this rectal screening program for our adult ICU so that once a week everybody in the ICU has a screen just to stay ahead of it by doing active surveillance. When we found a patient, enhanced communication around the whereabouts of that patient, making sure that everybody was doing the normal horizontal infection prevention measures. So we implemented that [and] thought things were rolling along quite nicely and then fast forward to March of 2018-that first case was July of 2017. And in March, we have our first case of NDM-1 Kleb pneumo from a rectal screen. So, again, [we] launch our normal investigation. This patient had been at an outside hospital for 24 hours and they were just in our hospital for a few days and were screened as part of our normal routine. We were able to identify that this patient was in the same room as the room that the first patient was in July of ’17. And we said, “Wow, there's something going on here.”

We decided to sample the sink based on the literature that has implicated sink drains and P-traps and shower drain P-traps in being persistent point sources for carbapenemase-producing organisms. We worked very closely with Amy Mathers and the UVA lab to learn how to appropriately perform those environmental cultures and help work them up, sent off those cultures. We also actually closed the room just out of an abundance of caution and we took out the sink because, again, based on what we had known from the literature, we were really suspicious that that was a persistent source. So lo and behold, the sink drain culture from the biofilm was positive for the NDM-1 Klebsiella pneumoniae. The P-trap water was negative. We had already replaced the sink and opened the room and deep cleaned just like we normally would have in the past. Then we thought, “You know, this is a really compelling story we need to share because here we are trying to stay ahead of CRE and [we] had implemented a very robust containment bundle. And yet, we still had this event happen.”

We went back and got 1 other case that was from 2015, the only other case that had ever been in the hospital, and that had been a patient with a risk factor of having had a liver transplant in India. That case was 3 years prior to the most recent case. We included that in our samples, bundled it up, and sent them off for whole genome sequencing. And then found out that patient 1, the one from 2015, was unrelated to the second patient and the third patient and the sink, and the second patient, sink, and third patient were all closely related isolates. And so this told us, “Wow, this was the smoking gun. Thank goodness, we removed the sink early on.”

The takeaway for everyone is that 1) as we already know, bacteria are always 1 step ahead, or probably 20 steps ahead, from us. And that, despite really aggressive prevention efforts, we found that the sink had become contaminated. This really leads us to believe that better education around sinks, particularly separating clean and dirty tasks, so thinking of having in ICU rooms, or in the hospital, where these really acute patients might be that might have these organisms, really having a sink that's dedicated for hand hygiene and clean things. And then an area that's used as a drain or for things like when you're performing peri care or bathing, where you've touched the patient and then that goes in the wastewater, that's considered dirty, you don't wash your hands there.

And then really, again, doubling down on your efforts to enhance horizontal infection prevention strategies, cleaning, particularly non-dedicated patient equipment, and really performing enhanced cleaning in the environment. My thought is that for hospitals that might not routinely see patients with CRE, or NDM-1 in this case, that if you were to detect a case, perhaps prospectively sampling that sink after their stay to see-we don't know the sensitivity or specificity of that, but-as a potential prevention measure, identify if there's colonization there and mitigate it before it becomes a problem. In our case, we’ve since performed many, many cultures on patients and haven't had any additional NDM-1 so we feel that because it was just in the sink drain and not the P-trap water, that it hadn't yet gotten to plumbing that couldn't be mitigated as easily.

I think that, as everyone knows, CRE is one of the most concerning pathogens out there and I just always want to put in a plug for microbial stewardship as a way to help stop the development of multidrug-resistant organisms in general. And that, again, basic infection prevention measures can really help stop the spread as well.

The study, What's Lurking in the Drain? Serial Transmission of NDM-1 Klebsiella pneumoniae to Patients Admitted 9 months Apart to the Same ICU Room, was presented Saturday, October 5, 2019, at IDWeek 2019 in Washington, DC.

Infection Control Today, Dec 2019 (Vol. 23 No. 10)

December 2019 Bug of the Month

Exploring CDC Guideline Updates for Infection Control in Healthcare Personnel

Enhanced Barrier Precautions: A New Approach to Preventing the Spread of Multidrug-Resistant Organisms in Nursing Homes

On High Alert: How Infection Prevention Changes in Outbreak and Exposure Situations

Disinfecting Duodenoscopes: Does the Method Make a Difference?

UV Disinfection Tackles MRSA-What About C difficile?

A Case of Serial Transmission of NDM-1 Klebsiella pneumoniae Tied to a Hospital Sink Drain