Coordination of what?

I’m glad that the new CDC Vitals Signs report, based upon a modeling study of the impact of regionally-coordinated interventions to reduce healthcare associated infections (HAIs) due to selected multiple drug resistant organisms (MDROs) and C. difficile, is gaining some media attention. The investigators modeled three different scenarios for control: (1) status quo, (2) “augmented” efforts at selected individual facilities, and (3) augmented activities coordinated across a health care network. Using data from various sources to inform the model (Emerging Infections Program and National Healthcare Safety Network for disease burden; Orange County, California and the VA system for patient movement across healthcare facilities; and experience from the UK and Israel for reductions in MRSA, C. difficile, and carbapenem-resistant Enterobacteriaceae (CRE) after national interventions), the model suggests that prevention approaches coordinated by public health authorities could reduce HAIs due to CRE by 55-74%.

This analysis has several limitations, most of which are pointed out by the authors in their discussion—models are models. And I don’t think anyone disagrees that coordinating infection prevention activities across healthcare systems is a desirable goal. The sad fact, though, is that we are very far from achieving this goal. I think Judy Stone has a good take on this, here. Furthermore, even if public health funding were increased enough to provide resources for state and regional coordination of MDRO control, the impact would depend upon each facility’s capacity to implement basic infection control practices (as the authors point out, “Optimizing implementation of basic infection control practice within individual facilities will be of fundamental importance to this effort”).

So while we wait for the inevitable boost in public health funding that is sure to come from our current Congress, we should remain focused on improving the basic “horizontal” infection control practices of individual facilities. It is not possible to know in advance which patient harbors a life-threatening bacterial pathogen (resistant or not), so it is best to assume that everyone does.

Regional Control of a large KPC outbreak: The Israeli Experience

The oubreak DID NOT occur here.
However, it IS St. Patrick's Day.

Hello everybody.  I hope you're all having a great St. Patrick's Day and a great Match Day.  Not sure those two days should be combined, at least for the safety of the future of the medical profession, but for some reason, that decision is not left up to me...

There is a report out electronically in CID (scheduled for April 1) by Mitch Schwaber et al. that describes the containment of a country-wide, carbepenem-resistant Klebsiella pneumoniae outbreak in Israel.  The outbreak of a highly-resistant strain, typically susceptible only to gentamicin and colistin, began in 2006 in multiple Israeli hospitals. The resistance was mediated by KPC-3 and local efforts to control the outbreak were largely unsuccessful. By March 31, 2007 there had been 1275 patients in 27 hospitals affected (13,040 beds).

In March 2007, the Israel Ministry of Health implemented a 3 component intervention: 1) Mandatory reporting of every patient with a carbepenem-resistant Enterobacteriaceae (CRE); 2) mandatory contact isolation of all known CRE carriers within self-contained nursing units in single rooms or cohorts with dedicated equipment AND dedicated nursing; and 3) creation of a nationwide task-force with statutory authority to intervene as necessary to control the outbreak.

Did it all work?  Well, they probably wouldn't have published this if it didn't work. They'd still be working too hard trying to stop the problem!  From the peak of 185 cases (56 cases/100,000) in March 2007 (92% of CREs were Klebsiella) infections fell to a low of 45 (12 cases/100,000) in May 2008, a 79% decline. I have pasted the incidence curve below. So it worked, but there are still too many CREs. If they let their guard down, the outbreak could easily reoccur.

As far as the study design, the usual caveats apply.  Despite great statistical control, they did not include a non-equivalent control group, etc, so perhaps these findings could be partially explained by regression to the mean or other biases, such as non-recorded interventions. Do I think that is what is going on here?  No.  I think the nationwide effort probably worked and their analysis and interpretation are correct.  This overwhelming response might be needed more often in the future given the lack of new antimicrobials, poor overall support for infection control (everywhere, not just in Israel) and continued overuse of the antimicrobials we do have.

Reference: Schwaber MJ et al. CID April 2011

Note: Dan posted on the CDC Guidance for Carbapenem-Resistant Enterobacteriaceae a couple years ago.

MRSA is a regional problem too

Years ago, Belinda Ostrowsky, then at CDC, showed in the NEJM that VRE could be controlled through regional infection control efforts in the Siouxland region of Iowa, Nebraska, and South Dakota. David Smith, then at NIH, was motivated by this success to test whether this regional response was necessary for control of a generic hospital pathogen using mathematical models. (see his PNAS study). He found that regional coordination may be necessary. So what about MRSA?

Hajo Grundmann and others in Europe have just published a very interesting paper in PLoS Medicine with an accompanying editorial by Frank Lowy. The authors collected MSSA and MRSA samples from 450 hospitals in 26 countries during 2006–2007 and completed spa typing on all of the isolates to determine genetic relatedness. They then geographically mapped the spa types. What they found was the unlike the widely distributed MSSA, dominant MRSA spa types formed distinctive geographical clusters within regions. Check out their interactive map (here). I think this shows that regional efforts will be required to control the spread of MRSA since it appears that it's mainly spread by patients who are re-admitted to different hospitals.

I won't begin to suggest what those efforts should be, but we certainly have multiple potential interventions and a single approach won't work in all places all of the time. However, since JJ Furuno's Archives of Internal Medicine paper a few years ago found that patient self-report of a hospital admission in the previous year detected 76% of MRSA carriers on admission, we have been using this regional spread hypothesis to control MRSA at University of Maryland Medical Center. Instead of obtaining nares swabs on 100% of admissions, we've swabbed only the highest-risk patients (admissions in the past year to any hospital and/or active skin infection) and detected and isolated almost all patients who subsequently developed MRSA infections - saving lives and saving millions of dollars too. Dollars we can spend to reduce CLABSIs or SSIs or another MDRO.