Everything old is new again, with WGS!

As we’ve pointed out, whole genome sequencing (WGS) is the hottest new tool to help us decipher the epidemiology of healthcare-associated pathogens. Last week’s NEJM included a study using WGS to investigate the molecular epidemiology of C. difficile disease (CDD) in Oxfordshire, UK. In a 3.6 year study that included 1223 CDD patient isolates, the investigators found that only 333 were genetically related to at least one previously obtained isolate. Of those 333, only 126 (38%) had nosocomial exposure to the earlier patient. And the finding receiving the most attention: 45% of strains isolated were genetically distinct from all previous isolates.

The take home point? In current hospital settings (where we isolate every known CDD patient and use enhanced environmental measures to try to eradicate their C. difficile spores), symptomatic CDD cases are no longer the major reservoir for C. difficile acquisition. Focusing only on transmission prevention, then, will have a limited impact (antimicrobial stewardship, anyone?). Most obviously, further work is clearly needed to identify other sources of exposure and acquisition of C. difficile.

This may come as news to many, but probably not to Matt Samore, who made a similar observation….in 1994.

Why validation is important

A new study in the American Journal of Infection Control describes the validation of publicly reported central line associated bloodstream infection (CLABSI) data in Colorado. The study encompassed a review of data from ICUs at 35 acute care hospitals and 8 LTACHs for the first quarter of 2010. Charts of 519 patients with positive blood cultures were reviewed. Results of this study, as well as 3 other statewide CLABSI validation projects are summarized below.

	Sensitivity	Specificity
Connecticut	48%	99%
New York	74%	95%
Oregon	72%	99%
Colorado	83%	99%

These 4 studies show that 17-53% of CLABSI cases were misclassified as non-CLABSIs, primarily due to labeling CLABSIs as secondary bacteremias. Interestingly, the Colorado study attempted to delineate the underlying causes of misclassification. Two reasons were found to be significant: lack of an electronic medical record or data mining software, and review of potential cases by an infectious diseases physician (i.e., post-surveillance certification).

Given all the attention paid to publicly reported HAI data and the important implications with regards to reimbursement, it's imperative that hospitals produce valid data. However, validation projects remain infrequent due to their cost. We have a long way to go...

Dr. Donald Low on Dying with Dignity

Toronto ID physician Donald Low died last month secondary to a brainstem tumor. Here he discusses his thoughts on the diagnosis, telling his family and his fear of losing control. An amazing person to the end.

Source: Toronto Star

The Antimicrobial Hospital Room

Earlier this month I gave a talk at ICAAC where I shared my thoughts concerning the role that environmental coatings and antimicrobial textiles might play in limiting pathogen spread in hospital settings.  Several readers asked for copies of my talk, so I thought I'd just post a (moderately) modified version here.  In the same session, Mike gave an excellent talk describing the primary importance of hand hygiene, Andrew Stewardson discussed the counter point that hand hygiene wasn't the most important intervention and Andreas Widmer covered no touch disinfection methods (e.g. UV light hydrogen peroxide vapor). A great session - wish you were there!

NIH KPC Outbreak - The Final Word?

We've covered CRE extensively over the past couple of years.  Never so extensively as we did when the 2011 NIH KPC outbreak was first publicized last August following the whole-genome sequencing report in Science Translational Medicine. Almost a year has past since that report and kerfuffle, so it is nice to see that Tara Palmore and David Henderson have found the time to share their experiences controlling the outbreak and the media storm that followed the publication of the original manuscript. They decided to label the section on the public reaction the "Unintended Consequences of Publication." This title is very disturbing, as it highlights why many outbreaks like these are never reported - publication bias. I'm glad they weren't afraid to publish again, so that we can all learn for this difficult outbreak. The report is freely available in PDF over at CID. I'll stop writing and let you get on with your required reading.

In praise of the fist bump

A new paper in the Journal of Hospital Infection piqued my interest. It's a study about the fist bump. The investigators did an analysis of surface area and duration of contact comparing the handshake to the fist bump. They found that the surface area of the palm is about 4 times larger than that of the fist, and the handshake lasts 3 times longer than the fist bump. Like social distancing, cough etiquette, and bare below the elbows, the fist bump may be another simple behavior that could have the ability to reduce transmission of infection. It's worth exploring.

Photo: In These Times

"I am isolated here..."

The October issue of Infection Control and Hospital Epidemiology has an interesting paper on contact precautions by the University of Maryland group. This prospective cohort study of over 500 patients used standardized interviews to compare perceptions of inpatients who were cared for under contact precautions versus those who were not.

Patients who experienced contact precautions were twice as likely to report problems with their care. Specifically these patients noted poor care coordination and a lack of respect for their needs and preferences.

One particular quote from a patient stands out:

“I am isolated here. When people put on the gowns, I feel dirty and alone… [They] even had to wear them when I was being wheeled around for tests.”

So in a nutshell, another study tells us that contact precautions is a patient unfriendly intervention.

Photo:  Bob Tymcyszyn/QMI Agency in the Toronto Sun.