By Gary Evans, Medical Writer
With the recent CMS action1 to begin enforcing Legionella controls in hospitals, infection preventionists can find a wealth of compliance resources in a newly updated CDC Water Management toolkit.2
“Think of this as part of you continuing quality improvement plans,” said Matthew Arduino, DrPH, MS, RM(NRCM), M(ASCP)CM, FSHEA, senior advisor for environmental hygiene and infection prevention at the CDC. “You are going to do your risk assessment and identify your critical control points where you can actually do something. You’re going to establish your limits, and come up with monitoring procedures.”
Aruduino emphasized that the CDC toolkit allows some flexibility in reviewing the basics of the guidance recently in Portland at the annual conference of the Association for Professionals in Infection Control and Epidemiology (APIC).
Decide “what you’re going to measure and how you’re going to measure it,” he said. “It could be as simple as monitoring disinfectant [levels] and water temperature — making sure your hot water is sufficiently hot. That’s something [you can work] with your engineers on. Identify your corrective actions if something were to [fail], then verify your procedures and document your program.”
As an environmental microbiologist, Arduino reminded that just because you find a pathogen in your water system, that does not necessarily mean you are on the eve of an outbreak.
“Presence alone does not equal risk,” he said. “Remember when we do sampling it is a point in time; it may not be consistent. And sometimes with water systems you can resample, and some of these things can be transient.”
Though the CDC document primarily focuses on Legionella elimination efforts, remember that other waterborne bugs may survive treatments designed to eradicate Legionella.
Some hospitals hire a water system consultant, but Arduino recommended that the local team still maintain ownership and responsibility for any decisions.
“Someone on the program team must have knowledge of the hospital’s water system,” he said.
This is presumably obvious, but Arduino has been to hospital outbreak investigations where there was no schematic of the plumbing and water system available.
“In one outbreak, they discovered they had a pipe that ran down to the end of the hall, [saying] ‘we don’t even use that anymore,’” he said. “Who involved in your assessment is going to identify those kind of locations? What is your corrective action? Document and configure your progress performance and communicate regularly. Develop a schematic — it could be hand drawn. Remember, some facilities have multiple points of entry and some may be interconnected.”
Likewise, if you have emergency water storage, know how often the supply is “turned over” and how that reservoir is connected to the rest of your water system, he said.
“You want to consider special patient populations at distant points,” he said. “Base it on your map of your facility. Make sure the program is running as designed and is effective, so you want to verify the cleaning and that the program is embedded and implemented as you designed it. That [means] you are controlling the hazardous conditions that you have identified, and that you may be monitoring for Legionella, especially in facilities with LD or with patients at high risk. It may include surveillance of patients for waterborne infections, and it may include testing for other pathogens — especially during an outbreak.”
Or Never Left?
Showing evidence of a water management plan could be the difference in avoiding a citation from CMS, which said hospitals must begin trying to control and prevent Legionella “effective immediately.”1
CMS surveyors “are going to be looking for you to have these these things in place: policies, procedures, reporting documenting water management in place — at least that you have started it,” Janet Stout, PhD, president of the Special Pathogens Laboratory in Pittsburgh, said at the APIC session. “You need to do a risk assessment as soon as possible to determine if these organisms are growing. Implement the water management program and document corrective actions — this is all in that [CMS] memo. [They] hammer home an important point about healthcare Legionnaires’ disease — the mortality is high.”
Having studied Legionella since the first highly publicized outbreak in 1976, Stout sees positive benefit in the the CMS regulation.
“I’m a glass-half-full person,” Stout said. “This is going to light the fire to prevent more Legionella. We don’t want to just react to Legionella [after cases have occurred] — we want to prevent it.”
Much as when it first appeared, it seems Legionella has made a dramatic return. But all may not be as it appears, neither then nor now, she notes. It was 1976, Rocky won the Oscar for Best Picture, and a large gathering of Legionnaires were staying in a hotel in Philadelphia, the very city where the movie was shot. This population of elderly men, with smoking much more common amid the drinking of the social gathering, were susceptible to Legionella being aerosolized from the hotel’s air conditioning system. A total of 221 people were infected and 32 died with what became known as Legionnaires’ disease (LD). A “mystery” bug capable of a 14% mortality rate in such an insidious fashion made the cover of the major news magazines.
“There was essentially panic,” Stout recalls.
However, Legionella was actually not new, it was simply going undetected, Stout said.
“It wasn’t epidemic, it was endemic,” she told APIC attendees. “It was there all the time but we didn’t know it because we weren’t testing for it. We weren’t testing the water for it, and we weren’t testing the patients for it.”
Legionella Is Not Ubiquitous
Stout was the lead author of a subsequent 1982 paper that said Legionella was “ubiquitous” in water, sparking a debate about whether it was worth testing for it in hospital water systems.
“Sometimes we regret the use of that word in the title of that article because ever since then, people have been saying Legionella is everywhere,” Stout said. “[People say], if it’s ubiquitous, then why test for it because we are going to find it everywhere. That is not true. The studies that have been done of hospitals and other buildings show that about half of the buildings will have Legionella in them. So, one of the things that is important for you to know is, what half are you in?”
Highlighting some recent CDC data that show LD is increasing, Stout said that better diagnostics and a heightened index of clinician suspicion in part explain why a surveillance graph of cases is “going in the wrong direction.”
“The number of Legionella patients have gone up dramatically over time,” she said. “Over 200% in the last 10 years. Why are the numbers going up? There are a couple of things that really are dramatically affecting this. Certainly, the diagnosis — people are thinking about LD more. Physicians will see a patient with healthcare-associated pneumonia and instead of just treating it like it is pneumococcus, they may do a Legionella diagnostic test. So, certainly with the increased understanding and use of more diagnostic tests, the more we are going to find.”
Weather patterns also play a role, as both heavy rain and drought can affect the quality of water going into municipal treatment plants. In a drought situation, the water recedes and more organic material in riverbeds gets mixed into the water. Similarly, heavy rain events stir up turbulent organic material and soil into the water, creating opportunities for Legionella growth.
Another factor may be aging population demographics, creating a larger pool of people who may develop illness if the waterborne bacteria is aerosolized and inhaled. That said, the presence of Legionella in the water alone does not necessarily mean people will become infected.
“Three factors [are involved],” she said. “It has to be pathogenic [species of] Legionella; Legionella pneumophila primarily is the one causing infection. Then, it has to get from water into the patient, who then has to be susceptible.’’
The Legionella in the water can get into the patient’s lungs if it is aerosolized in a shower or aspirated into the air from a sink or faucet. If the patient that is exposed is immunocompromised or has other risk factors like smoking, they may develop LD.
“One of the things you probably don’t know is that about a quarter of cases have none of those risk factors,” Stout told APIC attendees. “So, if you tell yourself you only have to look for Legionnaires’ disease in those highly compromised cases, you are wrong. Most of the cases are not in an outbreak — they are sporadic, meaning one here, many months go by, even years, and there is another one. This is important because when people identify a case, they start to panic because they think it is going to break out like the LD outbreaks.”
The pathogen can survive various water treatments, and likes warm water where it collects in biofilms, where bacteria form synergistic communities and share nutrients. Despite the increase reported by the CDC, Stout says many cases are still missed, citing a 2011 study where 41% cases were missed despite following testing guidelines for pneumonia by the Infectious Diseases Society of America.3
“That’s why there are more cases than you know. They’re missed,” she said.
In addition, with an incubation period of two to 10 days, many cases are missed because patients typically are discharged by five days at the most, she added. This is particularly relevant to hospital-acquired cases, which are only confirmed as such after a stay of 10 days. The variety of water treatments for Legionella include maintaining the hot water at a sufficient temperature and using chlorine or other chemical treatments.
“Legionella is in the water. If you kill it in the water, you have less cases,” Stout says. “It is not the concentration or growth of Legionella in a water sample — it is how many of the fixtures within the distribution system are positive that is predictive of illness. The risk of LD is better predicted by the proportion of water sites testing positive than by concentration.”
Studies suggest 30% seems to be a threshold, with increases beyond predictive of an outbreak, she noted.
“If you test 10 fixtures and more than three of those are positive, our studies and CDC studies say that as proportion goes up, the risk of exposure goes up and the risk of disease goes up,” Stout said.
According to the CDC water management plan, healthcare facilities should be wary of Legionella growth in areas:
- where medical procedures may expose patients to water droplets, such as hydrotherapy;
- where patients are more vulnerable to infection, such as bone marrow transplant units, oncology floors, and ICUs;
- with ice machines, where patients with difficulty swallowing may suck on ice for moisture.2
Of all the complex issues raised by Legionella detection and testing in water, there is one activity about which Stout gives full warning: chasing zero.
“People in your organizations are going to ask you, ‘Is there some magic number? Some acceptable level of Legionella above which we are going to have cases, and below which we are not?’” she said. “The answer is no, because it is a multifactorial event, including who is exposed, what kind of Legionella, and whether it gets into their lungs. I want to [warn] you about chasing zero. And what I mean by that is everybody wants everything to be black and white. I want no Legionella ever in my water system, but I can tell you as I stand here today — after studying this organism for more than 30 years — you won’t get to zero, and more importantly, you don’t need to be at zero. But if you wait and you have a case, and the health department comes to the facility — they [may] try to make you get to zero, and it is a nightmare. It is a loop you will have tremendous difficulty getting out of. Don’t wait. It is virtually impossible to achieve zero Legionella in a complex water system.”
The point, she emphasized, is not to get to zero Legionella in the water, but zero LD infections in patients. The polar opposite of an obsessive search for Legionella is the “no news is good news” approach taken at too many hospitals who would rather not look for the bug. This approach was famously summed up by the late Bruce Dixon, MD, who Stout quoted as saying, “If you don’t look for it, you don’t find it. If you don’t find it, you don’t think you have a problem. And if you don’t think you have a problem, you don’t do anything about it.”
At a recent CDC press conference, Hospital Infection Control & Prevention asked the CDC to clarify its position on Legionella testing and when an outbreak investigation should begin.
“Our current recommendations are that one case of definite healthcare-associated Legionnaires’ disease should prompt an investigation or two cases of probable healthcare-associated infection that occur within 12 months,” says Anne Schuchat, MD, acting director at the CDC. “Those are signals that there might be a bigger problem and that perhaps there’s some lapses in the water management plan. In terms of whether routine testing for Legionella is recommended or not, we really updated our tool kit to be in line with the ASHRAE 188 guidance document. That is somewhat ‘agnostic’ on the testing. The most important thing is to have a water management plan. Some plans will include testing; some don’t. But most important thing is to get the team together to assess the building, to develop the management plan, to follow it, and to make corrections when you have problems. That’s really where we stand on that. The very important issue is to make sure that we can protect patients in these settings.”
- CMS. Center for Clinical Standards and Quality/Survey & Certification Group. Requirement to Reduce Legionella Risk in Healthcare Facility Water Systems to Prevent Cases and Outbreaks of Legionnaires’ Disease (LD). Ref: S&C 17-30-ALL. June 02, 2017: http://go.cms.gov/2r3ue6B.
- CDC. Developing a Water Management Program to Reduce Legionella Growth & Spread in Buildings: A Practical Guide to Implementing Industry Standards. Version 1.1 June 5, 2017: http://bit.ly/2sdSW9a.
- Hollenbeck B, Dupont I, Mermeal LA, et al. How often is a work-up for Legionella pursued in patients with pneumonia? A retrospective study. BMC Infect Dis 2011; 11: 237. Published online 2011 Sep 7. doi:10.1186/1471-2334-11-237