Transcript for CDC Telebriefing: New Vital Signs Report – Can effective water management programs prevent building-associated Legionnaires’ disease outbreaks?

Press Briefing Transcript

Tuesday, June 7, 2016, 11:30 a.m. ET

Please Note:This transcript is not edited and may contain errors.

OPERATOR: During the question-and-answer session please press star one if you’d like to ask a question. Today’s conference is being recorded.  If you have any objections please disconnect at this time. I’d like to turn the meeting over to your host.

KATHY HARBEN: Thank you.  Thank you all for joining us today for the release of a new CDC Vital Signs.  This month’s vital signs is about Legionnaires’ disease outbreaks investigated by CDC from 2000 through 2014 and opportunities for prevention.  We’re joined today by the director of CDC Dr. Tom Frieden.  We also have Cindy Whitney who is chief of CDC’s respiratory diseases branch. Jasen Kunz an environmental health officer in CDC’s Environmental Health Services Branch is also joining us for the Q&A.  I will turn the call over now to Dr. Frieden.

TOM FRIEDEN: Thank you for joining us on this call.  CDC works 24/7 to protect the health, safety and security of all Americans.  We identify health threats and address them.  Today’s vital signs is on Legionnaires’ disease.  We’ve looked at outbreaks we have investigated over the past 15 years and we’ve identified crucial ways that building owners and managers can prevent Legionnaires’ disease with better water system management programs.  I will give you the bottom line right up front.  Almost all Legionnaires’ disease outbreaks are preventable with improvements in water system management. Let me step back and emphasize, as you may know, that Legionnaires’ disease is a serious lung infection. It causes pneumonia and symptoms include cough, shortness of breath, high fever, muscle pains and headaches.  About 10 percent of people who get this infection will die from it and it’s of particular risk to the elderly and those with suppressed immune systems or other underlying health problems.  It’s very important that doctors correctly and promptly diagnose and treat patients with Legionnaires’ disease because it does require particular tests to be diagnosed and antibiotics to be treated.

The bacteria that causes legionella is spread by contaminated water drops that are small enough to be inhaled as mist.  There are many types of bacteria around us all the time and there’s no way for us to eliminate all of them; nor is there a need for us to eliminate all of them.  Many are present at low levels and do no harm.  For legionella the key is to keep our water systems well maintained to reduce the risk that the germ will grow to large numbers and spread so that people become ill.  Legionnaires’ disease was discovered in 1976 by CDC scientists during one of the largest respiratory disease investigations in U.S. history.  CDC’s disease detectives are often called on to solve mysteries about health threats.  When people attending the American legion convention at a hotel in Philadelphia became sick, investigation suggested that the source of infection was a pathogen being spread by the hotel’s air conditioning system.  The legionella bacteria was first identified by CDC exactly 40 years ago this July.  And it reminds us that there are many advances we still need to make.  Just as we worked to solve that mystery, we’ve continued working to prevent Legionella and Legionnaires’ disease.  Again, the bottom line is that we now know that almost all Legionnaires’ disease outbreaks are preventable and let me give you the facts from this vital signs report.  For the 15-year period review, we investigated 27 building-associated outbreaks.  Most occurred because water systems were not well maintained.  There were a series of problems that we identified.  These included inadequate disinfectant levels, human error and equipment breakdowns.  These can be prevented through more effective water system management.  We looked overall at 415 cases of Legionnaires’ disease and 65 deaths.  Although this analysis looked at outbreak-associated cases, our scientists believe that most other cases are likely caused by similar errors and preventable by similar measures.  It’s just easier to identify the problem if you have many cases in an outbreak, than if you have sporadic cases.  While we still need to learn more about Legionnaires’ disease, it’s clear that people are unnecessarily getting — and avoidably — getting sick and dying from preventable infections.

Furthermore, the number of people diagnosed with Legionnaires’ disease has been increasing.  That number quadrupled from 2000 to 2014 and now each year about 5,000 people in the U.S. are diagnosed with Legionnaires’ disease. On average, we see at least 20 different outbreaks.  We believe that the increase is real and it’s likely due to a combination of factors including the increasing number of people who are at risk for Legionnaires’ disease because of the aging of the population, the increase in chronic illness, and the increase in immune suppression through use of medications to treat a variety of conditions.  We also have an aging plumbing infrastructure and that makes maintenance all the more challenging.  It is also possible that increased use of diagnostic tests and more reliable reporting are contributing to some of the rise in rates.  The outbreaks are costly.  For one year alone insurers paid an estimated $434 million in hospitalization claims for Legionnaires’ disease nationally.  Large recent outbreaks of Legionnaires’ disease in New York City and Flint, Michigan, have brought attention to the disease and highlighted the need for us to understand why these outbreaks happen and how best to prevent them.  That’s why this vital signs is targeted to a specific audience that we in public health don’t talk with often enough.  Building owners and managers.  It’s not a traditional health audience, but in this case it’s the single most important one.  They are the key to environmental controls in buildings that we live in, get our healthcare in, and work in every day.

Let’s look at what we found through 27 building-associated outbreaks.  For each of them we looked at the location, source of exposure and problems with environmental control of legionella.  We found that hotels and resorts ranked number one, accounting for 44 percent of outbreaks, long-term care facilities 19 percent and hospitals 15 percent.  The outbreaks in long-term care facilities and hospitals affected more people and caused more deaths than outbreaks in other locations.  They accounted for 85 percent of deaths while hotel and resort outbreaks accounted for 6 percent.  This reflects the higher rate of underlying illness in patients who are infected in healthcare facilities.  The most common source of the Legionnaires’ disease outbreaks was potable water such as water used for showering.  That was the cause in most outbreaks, followed by cooling towers and then some in hot tubs or industrial equipment or decorative fountains or water.  Cooling towers are part of large air conditioning systems and typically sit on top of buildings.  Cooling tower outbreaks had more cases because they’re outdoors. Cooling towers can create plumes of potentially contaminated water that can drift out and affect more people.  Potable water outbreaks, on the other hand, usually affect people inside the building such as patients in hospitals or guests in hotels.  Twenty-three of the 27 investigations had enough information to evaluate what was the problem.  Where did the system break down?  And we found four different types of problems.  Nearly half had more than one of the problems.

The first were process failures such as not having in place a legionella water system management program.  This was the case in two-thirds of outbreaks.  The second were human errors such as a hot tub filter not being cleaned or replaced as recommended by the manufacturer and this was the case in half of outbreaks.  The third were equipment breakdowns such as a disinfection system not working itself.  And this was the case in also a third of outbreaks.  And the fourth were reasons external to the building itself and these are important to keep in mind, such as construction nearby or a water main break and this was also found in a third of infections.  These findings showed that Legionnaires’ disease outbreaks are preventable.  That’s why we’re calling for stepped up water management systems for buildings particularly those at risk for Legionnaires’ disease outbreaks.  There is a lot of work to be done.  First, building owners and managers can determine if their systems are at increased risk for legionella, if so they need a program.  Examples of the types of buildings that had such programs are hospitals, long-term care facilities and buildings that are taller than ten stories.  We’re urging building owners, managers, hospital administrators and others to introduce and look at what we’re introducing today, a practical guide to help them, it’s called Developing a Water Management Program to Reduce Legionella Growth and Spread in Buildings, a Practical Guide to Implementing Industry Standards.

This guide is based on the recent ASHRAE Standard 188.  ASHRAEe is an important institution that addresses standards. Their guide is written for building engineers and what our practical guide does is interpret this so that those responsible for building safety can use it to implement the water management program.  The feedback we received after ASHRAE 188 came out indicated that the standard was not easy to understand by people who weren’t building engineers. So we worked to develop this companion document spelling out recommendations for a broader range of people, including building owners and managers and public health officials.  We were able to develop the document and pilot it in Flint, Michigan, where people are actively working to improve Legionnaires’ disease control in the community and where so far this year we have not had a reported case.  This document was well received and will allow more people to get engaged.  It’s the first version.  It’s available for download and we welcome feedback to make future versions even more useful.  State and local officials may consider incorporating legionella water system management programs into licensing and accreditation requirements for healthcare facilities and consider looking at building and public health codes about these programs.  Public health officials can also investigate reports of Legionnaires’ disease promptly to prevent more people from getting infected. At the federal level  we’re working very closely with health, academic and industry partners to develop and evaluate guidelines and standards to prevent Legionnaires’ disease and I want to congratulate our colleagues at the VA who now require Legionnaires’ disease prevention programs to be instituted at all of their facilities.  Healthcare providers also play a critical role in making sure that patients know if they are at increased risk for pneumonia, including Legionnaires’ disease, and to seek care quickly if they develop symptoms of pneumonia. Healthcare providers should also test for Legionnaires’ disease in people with serious pneumonia, especially those requiring intensive care or who recently stayed in a healthcare facility, hotel or cruise ship.  During an outbreak investigation, it’s essential that doctors and other healthcare providers collect the appropriate samples from clinical cases including culture so we can analyze what the specific strain is in the laboratory and also from the environment so we can determine the source of exposure and see if they match.  Again, the bottom line is that almost all Legionnaires’ disease outbreaks are preventable with improvements in water system management and given the increasing number of Legionnaires’ disease outbreaks we’ve seen in the past few years, we urge those involved with building safety to look at this — look at and use this new practical guide.  At the end of the day, building owners and managers need to take steps to reduce the risk of Legionnaires’.  We can work together to reduce this risk and limit the number of people exposed, infected and hospitalized or potentially fatally infected with this serious infection.  So thank you very much and I would be delighted to take questions now.

OPERATOR: Thank you.  At this time we will begin the question-and-answer session.  To ask a question press star one on your phone. Once again, if you’d like to ask a question press star one and record your name. One moment as questions register.

OPERATOR:  Our first question comes from Mike with the “Associated Press,” your line is now open.

MIKE STOBBE: Hi.  Thank you for taking my call.  Two questions, if I may.  Dr. Frieden, you mentioned Flint.  Do you mind summarizing for us what was found in the investigation by the state and federal officials there, how many cases, how many were traced to drinking water, to any particular facility?  And the second question I had was about cruise ships.  I think I read that cruise ships weren’t included in this — in your findings.  Could you talk a little bit more about why they weren’t included and how many there are and whether the issues are the same on cruise ships as in the land-based buildings.

TOM FRIEDEN: Thank you.  I will give the highlight and then turn it over to Dr. Whitney to give the details.  In terms of Flint, Michigan, CDC did not do the investigation of the outbreak.  We have been focused on prevention going forward so we can share with you what we know, but that was not a CDC investigation.  In terms of cruise ships we do think the issues are similar with water system management, but because of unique environment on cruise ships there may be particular issues, whether it’s hot tubs or other water features.  Dr. Whitney.

DR. WHITNEY: Yeah, that’s right, Dr.  Frieden. During the time between 2000 and 2014 that we covered in our MMWR there were eight outbreaks that we participated in on cruise ships and again, their water systems are different, but it is things like hot tubs and the potable water where we do find the legionella.

KATHY HARBEN: next question, please.

OPERATOR: Thank you.  Participants, again, as a reminder if you’d like to ask a question press star one and record your name.  Our next question comes from Lena Sun from the “Washington Post.”

LENA SUN: Could one of you guys answer Mike’s first question about the Flint situation in more detail?  Also I was wondering whether Dr.  Frieden or one of the other folks could address the increase a little bit more.  Is it accurate to say it’s really quadrupled if the numbers that CDC reports is for — you know, the broader thing, legionellosis instead of Legionnaires’ disease?

TOM FRIEDEN: So I will start and Dr. Whitney will continue.  We do see a really substantial increase in cases.  The new diagnostics for legionella actually predate that increase.  They may be getting used for, but we do think this is a reflection of the increase.  If you look at figure 1, legionellosis is basically infection with legionella so that’s Legionnaires’ disease for all intents and purposes but we can have a little bit more specificity from Dr. Whitney on that.  This increase, again, may be partly that we’re looking for carefully and testing more patients, but we think it does appear to be a real increase.  We’re not certain of all the reasons for it.  I mentioned the increasing size of the vulnerable population in the U.S., but that clearly hasn’t increased at this rapid rate.  So there is still a lot we don’t understand about legionella.  One of the things that we’re doing to better understand it is apply the advanced molecular detection methods to legionella.  We have made a lot of progress on this but there is a lot more to be made.  Legionella is a large organism as bacteria — as microorganisms go — so doing the sequencing and coming up with a library of organisms and understanding which of them are pathogenic and which of them are non-pathogenic is really quite complex.  The number of legionella strains is large and many of them do not appear to cause human disease. So this is still a mystery that is being solved in terms of which are the most dangerous forms and how best to control them and why it’s increasing, but we’ve identified the bottom line here that we can prevent a lot of outbreaks by water system management.  But Dr. Whitney can speak more to both questions, both the Flint issue and the trend.

DR. WHITNEY:  Sure. First about the increase, I think Dr. Frieden, you covered it well, the reasons we think the increase might be happening.  With regard to what’s legionellosis and what’s Legionnaires’ disease, legionellosis is a catch-all term that’s all the conditions caused by this bacteria. The vast majority, we think over 99 percent of what gets detected and reported is Legionnaires’ disease, the pneumonia form.  There is this other condition, Pontiac fever, which is a mild, flu-like self-resolving condition that is sometimes also picked up as part of outbreaks or sporadic cases.  With regard to Flint, there are some data that state and local health departments have released about what’s known about those cases.  In 2014 and 2015 they had about 91 cases that were detected in Genesee County. Fifty of those, so more than half, were linked to a single hospital.  I want to emphasize that hospitals really are vulnerable to Legionnaires’ disease outbreaks. They have got patients that have — that are older, that have these susceptible conditions so it’s really, really important for every hospital to have a water management plan and to be actively looking for Legionnaires’ disease among their patients.

OPERATOR: Thank you, speakers.  Once again the floor is open to questions.  If you’d like to ask a question please press star 1 and record your name.  One moment to see if we have additional questions.

OPERATOR: Thank you so much. Our next question is coming from Sean Hamill from “Pittsburgh Post-Gazette.”  You may begin, sir.

SEAN HAMILL: Dr. Whitney, can you tell me two things about the MMWR.  One, am I reading this right, does the CDC still hold to the position that facilities should not be testing for legionella?  The statement in the past has been that if you’re continuing to test for it then vigilance is lower. Is that still the position?  And two, why didn’t the CDC as a result of all of this, also look into comparing the different disinfectant methods, you know, from chlorine, mono chloramine, copper, silver, etc. Why not even evaluate them or say what the CDC thinks is the best?

DR. WHITNEY:  Okay. First of all, the testing. We think that to prevent legionella — Legionnaires’ disease and legionella growth — in these complicated water systems you really need a multi-faceted approach.  First of all, if you are a hospital you need to be making sure you know where all your cases of Legionnaires’ disease are. Then you need to be carefully monitoring your water.  You need to be checking frequently your temperatures, your chlorine levels. In places like hospitals where there are a lot of susceptible patients, testing can be a good adjunct to really make sure your water is clean, but we want to emphasize that you can’t rely too much on testing. You really need all these other things that you’re checking to make sure your water is safe and you’re preventing legionella growth.  About the disinfectant methods, that’s a good question, there’s been a lot of different methods that have been touted as maybe being better than others.  This really is an area that needs more research.  It’s not something that CDC can own.  We really need partners to help take this up.

KATHY HARBEN: Next question, please.

OPERATOR: Once again, participants, if you’d like to ask a question please press star one and record your name.  At this moment I’m showing no other questions in the queue.

TOM FRIEDEN: Okay.  Well, I want to thank everyone for joining us today.  And go back to the bottom line here, which is that most legionella — Legionnaires’ disease — is preventable.  There are things that we can do simply that don’t have to result in high costs, but can save money and save lives.  There are standards and practical guides that allow us to take our human-built water systems that could have the potential to harbor legionella and implement programs that protect patients, guests, tenants and visitors of our buildings from Legionnaires’ disease.  I will also comment that I mentioned earlier legionellosis is a broader term, it does include some cases of Pontiac Fever as Dr. Whitney noted and I will just go back.  Legionella is — has a special place in CDC history because of the challenge and intensity of the 1976 investigation.  I will say that’s probably the first time I heard of CDC and I think it’s a time when many people recognized that CDC’s ability to find, identify and ultimately prevent health threats is essential to keeping American cities healthy.  So thank you all very much for what you’ve done to cover this. It is an important and somewhat complicated topic and one where we’ve learned a lot and we continue to have a lot more to learn.  So thank you very much.

KATHY HARBEN: Thank you, Dr. Frieden, for joining us today.  Thank you, also, reporters for joining us.  If you have follow-up questions please call the CDC press office at 404-639-3286 or you can e-mail us at  Thank you for joining us.  This concludes our call.


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