Thursday, June 25, 2015

When antibiotics don't work any more: Maryn McKenna's TED Talk

Maryn McKenna is a public health journalist whose stories, books and posts have been important for explaining antibiotic resistance to those not already immersed in its study. Her TED talk from last spring just became available - well worth the listen. If you want to read more, head over to her 'new' blog at National Geographic: Phenomena: Germination.

Thursday, June 18, 2015

The role of weather, season and climate in HAI

The recent attention given to climate change served as a backdrop to this talk (slides posted below) that I just gave at ICPIC in Geneva. ICPIC has been a wonderful conference and it was a nice forum for discussing the larger, international issues hindering HAI control. I look forward to seeing everyone again in two years.

Tuesday, June 9, 2015

MERS in S. Korea and Infection Control

I've been thinking about this all week, and came to the conclusion that I don't have much of a take on the latest outbreak. Surprising, I know, given how we are the number one "therapeutically abrasive blog"* on the interweb. With that said, I want to counter a meme I've seen emerging.

In Nature News today there was an article and a quote from David Heymann, chair of Public Health England, that I found a bit concerning. He said, “The focus on South Korea would be better directed towards Saudi Arabia.” It appears to me that the article and he are suggesting that it's more important to study episodic animal-to-human transmission than to focus on human-to-human infection control. I think this is a poor choice (or perhaps a poor choice of words) for a number of reasons. First, it is unlikely that prevention activities in Asia compete for research dollars with epidemiological investigations in the Middle East - we can and should do both! Second, in the case of MERS, CDC has estimated that more than 90% of cases could be linked to health care exposures. So, if we care about preventing incident human cases, public health authorities must still focus on understanding and halting nosocomial transmission. Finally, in a recent article in Time, the CDC's Tom Frieden said “Hospitals can become amplification points...It’s the case in measles, it’s the case for drug-resistant tuberculosis, it’s the case for MERS and SARS and Ebola. That’s where sick people go and that’s where vulnerable people are. It really emphasizes the importance of good infection control in the health care system.”

And if I can extend what Dr. Frieden said - we don't actually know how to achieve good infection control for MERS and the other pathogens he mentioned. If only we invested in studies to understand how to best implement PPE in these settings. One could imagine improved PPE technology, refined PPE donning and doffing algorithms and enhanced environmental cleaning as potential targets for future studies examining optimal protection from MERS. Not coincidentally, many of these are the same targets that Mike, Dan and I mentioned in our Ebola+PPE editorial several years months ago. If we invest in infection prevention technology and implementation research, our health care system will be safer regardless of the pathogen du jour.

For those interested in reading more about infection control for MERS, I suggest a recent review by Westyn Branch-Elliman, Connie Savor Price, Alison McGeer and Trish Perl in the March 2015 ICHE. ICHE has graciously made the review "free access" for the month, so download the PDF now. Of note, this group has first hand experience with MERS infection control in Saudi Arabia. Additionally, CID just published an invited review on MERS for clinicians that is also free access. Finally, for a recent update on the S. Korean outbreak I suggest this excellent article by Julia Belluz in Vox.

*I found "therapeutically abrasive" quite funny and think it could be very useful in preventing C. difficile

Saturday, June 6, 2015

This study is boring, and we need more just like it

What is there to say about a study that compares the treatment of an infection with X versus Y days of antibiotics? The recently published STOP-IT trial didn’t reveal groundbreaking new approaches to treatment or prevention, or provide keen insights into pathogenesis or transmission. The investigators simply compared two antibiotic treatment durations for abdominal sepsis: a short course after source control (~4 days), versus a more standard course that continued until fever, elevated white cell count and ileus had resolved for 2 days or so (to a maximum of 10 days). The verdict? No difference in outcomes (a composite of surgical site infection, recurrent intraabdominal infection, or death within 30 days). Our own Mike Edmond and Dick Wenzel penned the excellent accompanying editorial, to which I refer you for more detailed commentary.

I like this study, and we clearly need more studies that test our current approaches to antimicrobial treatment of common infections. “How long do we need to treat this infection?” is one of the most frequent questions we get as ID consultants, and it’s amazing how scant the evidence base is regarding duration of therapy. Studies like this one, and this oft-cited study that helped reduce our duration of treatment for ventilator-associated pneumonia, have the potential to markedly reduce unnecessary antimicrobial therapy, thereby reducing risk for C. difficile and antimicrobial resistance emergence, among other adverse effects of antimicrobial overuse.

Also of note, this study was published just in time for the White House Antimicrobial Stewardship Forum!

Thursday, June 4, 2015

Removing C. difficile spores from hands: Enter Sandman

Exit, light 
Enter, night 
Take my hand 
We're off to never-never land
-Metallica "Enter Sandman"

It is well known that hand washing, particularly with soap and water, is critical for preventing the transmission of C. difficile in hospitals. Evidence suggests that the mechanical friction of hand washing is the mechanism behind spore removal. However, is there a way to improve the friction when practicing hand hygiene? To answer this question, investigators at UCSF reported results of a study that compared C. difficile spore removal after washing with 5 different methods including: (1) negative handwashing control: 30 seconds of rubbing with 5 mL of water and 30 seconds of tap water rinsing; (2) 30 seconds of rubbing with 5 mL of 0.3% triclosan soap and 30 seconds of rinsing; (3) 30 seconds of rubbing with a paste consisting of 15 mL of sand mixed with 15 mL of tap water and 30 seconds of rinsing; (4) 15 seconds of rubbing with 5 mL of a 50% baking soda–50% vegetable oil mix and 15 seconds of rubbing with 5 mL of liquid dish detergent followed by 30 seconds of rinsing; and (5) 60 seconds of rinsing.

Lo and behold, washing with sand and water was superior to both the water rub/rinse (0.36-log reduction in spores) and tricolosan soap (0.50-log reduction) - see Table 2, below.

The authors claim that the sand/water method was well tolerated after a single use, although it's hard to imagine that repeated use would be well tolerated. Still, this study raises many interesting questions. For example, what if we used Lava soap containing pumice, or Brillo pads or what if we placed our hands in a rock polishing machine after seeing patients? All kidding aside, you could imagine high-density soaps that have increased friction without the nasty abrasion. In the meantime, I'm going to keep rubbing my hands on my corduroys. 

Tuesday, June 2, 2015

SSI Prevention Bundle in Cardiac, Hip, and Knee Surgery - A Home Run

...and I'm being modest...

As I mentioned yesterday, it's really hard to write a post when you've already written the accompanying editorial. Today, I have a taller task - posting on a study led by two close colleagues (and favorite people), Marin Schweizer and Loreen Herwaldt. (COI alert) Fortunately, JAMA Associate Editor, Preeti Malani, has done the heavy lifting with her excellent editorial.

In today's JAMA, Schweizer and colleagues reported the results of an AHRQ-funded trial examining the benefits of an SSI prevention bundle in orthopedic and cardiac surgery. The bundle was outlined in a meta-analysis they published in BMJ two years ago and included preoperative nasal screening for MRSA/MSSA, mupirocin BID and daily CHG baths for 5 days if screen positive and vancomycin added to perioperative prophylaxis if MRSA positive. The quasi-experimental intervention study took place in 20 US hospitals across 9 states with 39 months of pre-intervention SSI rates and 21 months of rates collected during the intervention period.

Overall, the results are impressive (i.e. not modest). First, there was a 42% reduction in SSIs after the intervention was implemented (see Figure, below), despite modest bundle adherence (39% full adherence, 44% partial adherence).

The key finding for me relates to the number of months where there were ZERO SSIs across all 20 hospitals. Looking at the Figure above, you can see that "the number of months without any complex S aureus SSIs increased from 2 of 39 months (5.1%) to 8 of 22 months (36.4%; P = .006 by Fisher exact test)." Seven times as many zero-months in all 20 hospitals. That's not a modest finding. ;)

Key points from the editorial:

"inclusion of patients undergoing emergency or urgent operations, a population recognized as at high risk for SSI, improves the generalizability of the findings."

"the primary study outcome was limited to complex S aureus SSIs, eliminating much of the subjectivity of infection surveillance. Even though surveillance practices varied among participating hospitals, complicated S aureus SSIs are not clinically subtle and can be identified easily by any surveillance system."

and given the modest adherence to the bundle, "Moving forward, efforts to promote and maintain adherence to prevention protocols will remain important"

"The study’s setting is among its limitations. All 20 study sites were from a single health care system with a well-established quality improvement infrastructure - certain factors in this health care system may differ from other clinical settings, including a below-average baseline infection rate. It remains unclear what challenges and barriers may present as this bundle is implemented at other institutions. Further studies in different settings will offer additional guidance."

and my favorite quote:"Although getting to zero is unlikely to be achievable, efforts that move closer to this elusive goal hold tremendous value for clinicians, hospitals, payers, and, most importantly, patients."

My final thoughts:
This is a wonderful study that took many years of planning, hard work and tremendous collaborators, including HCA and Ed Septimus. Congrats to all involved. Not every study is a grand slam, but we'll take a home run for infection prevention.

Monday, June 1, 2015

C. difficile and Hospital Process Measures: What Works?

One of the more difficult things to cover is a study that you've already written about in an accompanying editorial. It's quite hard to come up with anything "new" to write that you haven't already written. Such is the case with a very nice study examining hospital process measures and C. difficile infections just published in BMJ Quality and Safety by Nick Daneman and colleagues from Sunnybrook Health Sciences Centre in Toronto.

Using results of a mandatory CDI prevention practices survey they compared facility-level processes measures and patient level (via ICD-10 codes) CDI rates in 159 Ontario hospitals. Specifically, they looked at implementation of six hospital-level measures: (1) isolation at diarrhea onset, (2) audit of antibiotic use, (3) audit of environmental cleaning, (4) vancomycin as first line therapy and (5) on-site diagnostic testing and (6) reporting of rates to senior leadership. Somewhat surprisingly, none of the process measures were associated with lower risk of CDI.

In the editorial, Nasia Safdar and I wrote:

"First, the authors identified low self-reported implementation of most CDI prevention practices, with only 27% of facilities reporting isolation of all patients at onset of diarrhoea, and 16% reporting auditing of antibiotic stewardship practices. Low adherence rates for these two practices in particular are concerning because prompt institution of contact precautions is necessary to reduce nosocomial transmission of C. difficile. And antimicrobial stewardship is at least as important as infection prevention practices, if not more so, for reducing CDI."

"This study also highlights the importance of implementation science research to tackle the vexing yet pervasive problem of low and variable adherence to evidence-based interventions for reducing HAI, including CDI. The scope of this study did not extend to exploring barriers to implementation or an in-depth assessment of the self-reported practices that may help inform implementation strategies to increase uptake of proven practices."

and of course my favorite part:

"Last, increasing the evidence base for preventing CDI by undertaking pragmatic randomised controlled trials of novel interventions incorporating efficacy and effectiveness is essential to successfully bridge the quality chasm that currently exists in CDI prevention."

Reference: Daneman N. et al. BMJ Qual Saf. 2015 Apr 24 (open access)