Friday, February 12, 2016

SHEA Annual Meetings 2007, 2011, 2015 and Beyond?

A decade ago, I was a young associate professor of Epidemiology at the University of Maryland School of Medicine in Baltimore. One afternoon I received a call from Dr. Trish Perl, then President of SHEA and crosstown colleague. Two years earlier, she and I had met when we assisted with the infection control of Bob, an Atlantic Bottlenose Dolphin at the National Aquarium, who had been diagnosed with Mycobacterium abscessus pneumonia. She was not calling about marine mammals this time, but rather was asking me to serve on the 2007 SHEA Annual Meeting Planning Committee, as the local "Baltimore" representative. It was an amazing experience. For one, it was when I met future colleague, friend and co-blogger Dan Diekema and other mentors and colleagues - see the 2007 AMPC roster below.

Over the years I've been asked to serve on many other meeting committees including the last old format SHEA Scientific Meeting in Dallas (2011) and the first combined meeting, IDWeek 2012. As 2016 represents my last year on the SHEA AMPC, I've been looking back over the old committee rosters and reminiscing. What struck me most, besides the amazing colleagues I've crossed paths with, is the overwhelming presence of MDs, specifically ID-trained, on the committees. Looking at the rosters from 2007 (above) and 2011 (right) and excluding SHEA staff, 94% were ID physicians over both years.

The preponderance of ID physicians is not surprising, given that SHEA was founded by ID physicians and our board of directors roster is made up of ID physicians. However, the science and practice of infection prevention and stewardship is evolving into a broader multidisciplinary effort. We now frequently collaborate and learn from a variety of well-trained scientists and clinicians including medical sociologists, medical anthropologists, epidemiologists, biostatisticians, human-factors engineers, infection preventionists, general internists, MBAs, health economists, pharmacists, microbiologists and health psychologists among others.

When faced with the daunting task of walking in the footsteps of prior co-chairs, Lindsay Nicolle, Scott Fridkin, Charlie Huskins and Dan, we recognized that we had an opportunity to broaden the appeal of the conference and strive towards a truly multidisciplinary program. So in 2015, working with the SHEA board and staff, Susan Huang and I convened a Program Planning Committee (figure below) with 42% of its members trained in fields other than infectious diseases. 

This is not to imply that ~40% is the correct balance. Maybe it should be closer to the 15% of 2016. Perhaps future spring meetings will have an implementation focus and over 50% of the planning committee could be experts outside of infectious diseases and other years the focus could be diagnostics and the committee could be loaded with microbiologists. 

The important thing is that we realize that clinical and scientifically, SHEA and our meeting should not be defined by what we were (ID physicians) and what we are not (APIC), they should be defined by what we hope to achieve. And if we truly hope to prevent healthcare-associated infections and the emergence of antimicrobial-resistant pathogens, we need more than ID physicians. Plus, I think it will be a lot of fun!

Thursday, February 11, 2016

What happens when you flush a toilet?

Many of you know that I'm not a fan of the uncovered toilet in hospital rooms or anywhere for that matter. Over at Fast Company, they have an amazing post with high-speed video (included above) from Lydia Bourguiba, an MIT professor who studies fluid dynamics and disease. The focus of this 1000-2000 frame per second video is the small particle or aerosol transmission that occurs after a toilet is flushed, think C. difficile. Enjoy! Oh, and sorry to ruin your breakfast or lunch.

Wednesday, February 10, 2016

New ESCMID blog - Leveling the Field

The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) formed a Parity Commission in 2010 to address barriers and facilitators for women and minorities in the fields of clinical microbiology and infectious disease. To further their mission, the Commission has started an important new blog called "Leveling the Field." The first post titled "Between Privilege and Merit" was written by Dr. Angela Huttner, the current advocate for gender. The plan is for her colleagues on the Commission to contribute future posts. Their aim is to "convey the voices of all" involved and they invite us to contact them with our thoughts and experiences. If future posts are half as good as Dr. Huttner's, this blog will be one to check in on often.

Barriers exist outside of infectious diseases and microbiology and Nisha Mehta's recent post on KevinMD titled, "Why are female physicians scared to be women?" provides a description of many issues. And these are not confined to medical fields  - I would point you to this excellent post by Sarah Bond, an assistant professor in the UI Classics Department titled "The Decline and Fall of the All-Male Panel."

I would just close with a question - is it time for a similar platform in the U.S.?

Tuesday, February 9, 2016

Is it time to ditch CHG bathing in ICUs and get back to basic infection control?

We are at an interesting inflection point in infection control. On the one hand MRSA is in decline and VRE has flat or declining incidence in many national samples. Yet on the other, we have largely pulled back from what is considered traditional infection control practice. It is important for us to understand what may be driving the declines in MRSA (and to a lesser extent VRE) and on what shaky foundation these declines are actually resting.

The recent MRSA decline is due to multiple factors including the underlying epidemiology of the pathogen, host immunity and the emergence of effective antibiotics targeting MRSA that are not named vancomycin (e.g. linezolid, daptomycin, ceftaroline). These factors are intertwined. For example, recent CA-MRSA strains have susceptibility to many existing antibiotics (e.g. clindamycin, tmp-sulfa), which highlights the complexity of the underlying reasons for MRSA's decline. I should also mention the antibiotics CHG and mupirocin here too, but I'll get back to them in a bit.

During the past decade, we've also seen a decline in the importance of basic infection control. Many of you will disagree with this statement but let me explain. The cornerstone of infection control has always been hand hygiene compliance and yet very little "honest" attention is paid to it. There is now so much pressure to report hand hygiene compliance rates greater than 90% that we have hit the target without actually improving compliance. Over and over in studies at hospitals across the US where we've looked, hospitals are reporting compliance rates over 90% and it's actually 40-60%, when we look closely with independent observers. Why does this matter? Because when we believe it's 90%, we ignore it.

On top of our hand hygiene conundrum, contact precautions are no longer favored for MRSA prevention. A bit of history - the second ever post on this Blog back in 2009 was titled: "Why I hate Contact Precautions, vol. 1." So there's not much love here for ye olde CP. Which brings me to the point of this post (finally) - when we no longer have hand hygiene compliance, gowns and gloves and when the foundation of infection control is based on antibiotics like linezolid, CHG and mupirocin, what will we do when the foundation begins to crumble?  Will we even notice the crumbling or will we stick our heads in the sand and ignore it?

Many of the gains in infection control over the past decade have rested on the foundation of CHG bathing. Ignoring for now that CHG might select for Gram-negative pathogens that have fewer effective therapies, CHG use might also select for CHG resistance through efflux pumps coded by qacA/B, which has been associated with MRSA decolonization failures. Yet the long-term (and after a decade, we are getting longish) effects of daily CHG bathing are not well described.

Into this void, David Warren and colleagues just reported in ICHE 8-year trends in the epidemiology of MRSA strains after initiating daily CHG bathing in their SICU. A random sample of 504 MRSA isolates were selected for analysis (63/year). Among all isolates from 2005 (when CHG bathing was implemented) to 2012, 7.1% were qacA/B(+). Somewhat disconcerting was the rise of qacA/B from 6.2% (2005) to 16.9% in both 2009 and 2010. Also concerning was the finding that 25% of qacA/B(+) MRSA isolates were mupirocin resistant. Results stratified by timing of nasal swab collection are in the Figure above. In explaining this increase the authors noted: "qacA/B(+) isolates from 2009 and 2010 were more likely to have ≥1 hospital admissions in the prior year, suggesting a possibility of an expansion of qacA/B(+) MRSA at BJH during this time period, which resulted in qacA/B(+) patients in those years being exposed in prior admissions."

So where do these findings leave us? Yes, more studies, larger studies, bigger and better studies - $6 million dollar man studies. But pending those dream-like studies, can we state at what level of CHG resistance we should ditch universal CHG bathing?  Are we compromising the effectiveness of CHG in preoperative settings like those supported by STOP-SSI? And when can we get back to basic infection control? To my knowledge hand hygiene and gowns/gloves don't drive resistance like CHG. Well, except resistance from my esteemed co-bloggers and colleagues. ¯\_(ツ)_/¯

Monday, February 8, 2016

Guest Post: Thinking about Contact Precautions

Anthony Harris, MD MPH
This is a guest post from Dr. Anthony Harris, Professor of Epidemiology and Public Health, University of Maryland School of Medicine.

I have a lot of admiration for this blog and in the spirit of academics, I would like to share my somewhat different interpretation of the contact precautions literature. I offer three points for your consideration:
1. Contact precautions do not lead to an increase in adverse events: 

Instead of the frequently cited small observational studies, I think it is most important to focus on the one randomized trial that evaluated adverse events associated with contact precautions (I acknowledge my bias in that it is the study I led). A randomized trial should most often trump observational studies especially since it's near impossible to control for confounding by indication, i.e. why was the patient placed on contact precautions. In fact, the latest analysis of our randomized trial data showed a trend towards decreased adverse events in the universal contact precaution arm. (See: Croft L et al. Clin Infect Dis. 2015 Aug 15;61(4):545-53). To quote from the Conclusion: "Concerns of adverse events resulting from universal glove and gown use were not supported." So we should be clear that other than the cost issues of gloves and gowns no high level study has shown any adverse events from contact precautions. Healthcare workers do go into the patient room less often when the patient is on contact precautions but this has not been shown to lead to an increase in adverse events. In my experience (and the data supports this), healthcare workers just bundle their activities and thus perform the same activities in the room with fewer visits.

2. Methodological problems in studies that have removed contact precautions: 

Studies that show no effect of removing contact precautions have serious methodological problems. The largest problem is that they are incredibly under-powered. The studies that show “no difference when you remove contact precautions” are too small to detect a difference and thus may falsely conclude that removing contact precautions is safe.

3. Need a better solution before removing the current standard of contact precautions: 

As much as I would love to stop wearing gloves and gowns, antibiotic-resistant bacteria are a continuing problem. They are not going away and other than MRSA, they are not decreasing. Until we have better solutions, I believe that we should not be abandoning contact precautions. This is particularly true in high risk settings such as the ICU. In the ICU where acquisition of an MDRO leads to infection 20-30% of the time during the index ICU admission, the stakes are too high not to prevent patient-to-patient transmission. I believe that the phase 0, phase 1 and phase 2 data on contact precautions are strong and the biologic plausibility that they prevent patient-to-patient transmission so strong that I don’t think we should abandon contact precautions based on underpowered "removal studies" and an adverse-event literature with few studies with strong internal validity. Of course there are certain settings and certain bacteria where removing contact precautions might make sense and these scenarios should be studied using large, sufficiently powered and methodologically sound trials.

Saturday, February 6, 2016


This term, defined by Merriam-Webster as “causing harm in a way that is gradual or not easily noticed”, keeps occurring to me as we continue our investigation and response to a case of M. chimaera infection. Our early efforts to address the “not easily noticed” part of this problem is starting to bear fruit, with some increased media attention and an excellent piece by Maryn McKenna.

In this post I want to raise three questions about this situation (note that I say “raise”, not answer):

1. Why M. chimaera?

Why is this particular, uncommon species from within Mycobacterium avium complex (MAC) causing infections in multiple countries in Europe and multiple states in the U.S.? If the cause of this outbreak were simply a faulty heater-cooler unit (HCU) design that allows whatever water is placed in the device to be aerosolized, one would expect a greater variety of environmental flora to be implicated (other MAC species, environmental Gram negatives, etc.). And indeed, there has been concern regarding a link with some of the rapidly-growing mycobacteria (e.g. M. abscessus), that are often found in the hospital tap water used to fill the HCUs (until more recent guidance to use sterile or filtered water). However, the consistent finding of M. chimaera from patients exposed to HCUs suggests a “point-source”. Molecular typing or genome sequencing will be needed to confirm this, and I know some of this work has been done—I hope the results are published soon. It is extremely important to understand this, because a point source implies that the HCUs may already be contaminated when shipped to hospitals. The units are tested prior to shipping, so they do get filled with water at the factory, and the recent FDA warning letter suggests that the tests used by the company to monitor their disinfection and drying process at the factory are “inadequate”. If an organism like M. chimaera has already colonized the HCU (and formed a biofilm), good luck disinfecting it.

2. When should patients be notified as part of a look-back or case-finding investigation?

There are several hospitals across the U.S. that are working with public health officials (state or CDC) to respond to the identification of one or more M. chimaera infections. Obviously, notifying every patient who has undergone bypass for the past four years is a huge endeavor: resource intensive, generating bad press and patient anxiety. Undoubtedly there are hospitals that have decided not to do patient notification (which is why you’ve not heard about them).

So let me review our thinking on this. One of the first steps of any outbreak or exposure investigation is to do additional case-finding, without which it is impossible to understand the extent of the problem, and impossible to provide either preventive or therapeutic care to the exposed or infected. In some outbreaks, case-finding can be limited to record reviews because the infection essentially always comes to medical attention (e.g. MRSA bacteremia), or because it resolves without treatment if it doesn’t come to medical attention. For the reasons outlined by Mike, there is no way to know how many M. chimaera infections have occurred without doing notification—of both patients and providers. Thus once we learned about a case, we felt the only ethical option was to proceed with an extensive patient notification (in addition to the other case-finding using lab and patient records). If even a single exposed patient is being bounced from one specialist to another with prolonged FUO because nobody has reason to do mycobacterial blood cultures in someone with an intact immune system, we need to identify that person in order to provide therapy.

A counterargument would be that a nationwide notification should be performed, rather than these piecemeal notifications from individual centers that happen to find a case—however, it is not clear to me how that could be done, logistically, and we’ve learned in the past few days that the notifications from CDC and FDA in October of last year were insufficient at increasing awareness of the problem.

3. What should FDA be doing?

Note that I say FDA, not CDC—because CDC has no enforcement function. The agency that needs to step up aggressively to address this problem is FDA. As outlined here, they’ve already informed the manufacturer that they will block the shipment of new units to the U.S. until this problem is addressed. However, depending upon the answer to question 1 above, we are still left with 60-80% of all HCUs in US hospitals at risk for aerosolizing M. chimaera, with no way to know whether current cleaning and disinfection protocols are effective. The approach we’ve taken (to move the units outside the OR) is not feasible for many hospitals due to the requirement that the unit be within 5 meters of the patient. Likewise, it isn’t feasible to ban the existing units, as the supply of other HCUs is not sufficient and you can’t just stop doing heart surgery. The Sax group referenced construction of a containment unit for the HCUs that exhausted through a HEPA filter, but it isn’t known how that might impact the performance of the HCU. Other engineering solutions must be available, something that can be mass-produced and used to modify the existing units so that the exhaust is safe. In the era of 3-D printers and such, someone must be able to figure this out quickly!

Tuesday, February 2, 2016

M. chimaera infections associated with cardiopulmonary bypass

Dan and I have spent numerous hours recently on a particularly difficult infection prevention issue. We recently learned that a patient who underwent cardiothoracic surgery at our hospital developed an infection due to Mycobacterium chimaera. Last year, it was recognized that this organism is associated with heater-cooler devices used in cardiac surgery, and CDC and FDA put out alerts to hospitals in October 2015 regarding appropriate disinfection of these devices.

A paper in Clinical Infectious Diseases last year described an outbreak of these infections in Switzerland. The outbreak investigators determined that the water used in the heater-coolers became contaminated by M. chimaera. This water never comes into physical contact with the patient, but the investigators found that a fan on the heater-cooler unit aerosolized the organism into the air leading to direct contamination of the surgical wound. When the heater-cooler devices were present in the operating room but not turned on, the organism was not aerosolized.

Most of the reported cases have manifested as prosthetic valve endocarditis or vascular graft infections, and there may be involvement of the bone marrow causing cytopenias, as well as splenomegaly. The patients were not immunosuppressed. Often these patients presented with nonlocalizing symptoms, such as fever, mylagias, arthralgias, fatigue and weight loss. The mortality rate is approximately 50%.

Several issues make case finding problematic:
  • The time to diagnosis can be up to four years, as the incubation period for the infection due to this slow-growing mycobacterium is long, and diagnosis is often delayed since the organism isn’t detected in routine cultures.
  • Symptoms of the infection are often nonlocalizing.
  • We rarely order mycobacterial blood cultures in nonimmunosuppressed patients, and these cultures are key to making the diagnosis since most of the patients have infections of endovascular grafts or prosthetic cardiac valves.
  • Given that Iowa is primarily rural, many patients receive their post-operative care by local providers, making it more difficult to identify cases. 
For the reasons above, on the basis of a single case, we have embarked on a four-year look-back of 1,500 patients who underwent procedures utilizing cardiopulmonary bypass at our hospital. These patients are being instructed to call a toll-free number to be screened for symptoms that may be related, and then to undergo further evaluation if needed.

If your hospital performs procedures requiring cardiopulmonary bypass, the most important control measure to prevent infection is to move the heater-cooler devices out of the operating room. Our engineers were able to develop a solution and accomplish this within 24 hours. In addition, ensure that the devices are being disinfected according to manufacturers’ guidelines.

M. chimaera is one of 8 species in the M. avium complex, and was recognized as a a distinct species in 2004. Given the ubiquitous nature of nontuberculous mycobacteria, we suspect that the cases linked to heater-cooler devices reported to date represent only the tip of the iceberg, and it is likely that more hospitals will be facing extensive look-back investigations.