The Department of Veterans Affairs Veterans Health Administration’s active screening campaign to reduce methicillin-resistant Staphylococcus aureus (MRSA) continues to make significant progress, with healthcare-associated infections dropping 87% in ICUs from October 2007 to September 2015, researchers report.1
Lead author Martin E. Evans, MD, an infectious disease physician at the University of Kentucky in Lexington, reports that infection rates fell 80% percent in non-ICUs, and 81% percent in spinal cord injury units.
The VA implemented the MRSA Prevention Initiative nationwide in October 2007. It includes having a dedicated MRSA prevention coordinator at each hospital. Interventions include universal active surveillance on admission, which triggers contact isolation precautions for those colonized or infected with MRSA. The program also includes monthly updates on MRSA nares screening, clinical culture results, and data on patient movement. Hospital Infection Control & Prevention asked Evans to comment on some on the key aspects of the program.
HIC: This latest paper certainly documents continued success with your MRSA infection reductions. You also describe a “collateral effect” of this program in a previous paper.2 Can you explain what you mean by that term?
Evans: When we do MRSA swabs on admissions and find that patients are positive and put them in isolation, [we wanted to find out] how many times we accidentally get them in isolation for a gram-negative multidrug-resistant organism like an ESBL [extended spectrum beta-lactamase], CRE [carbapenem-resistant Enterobacteriaceae], multidrug-resistant Pseudomonas, or Acinetobacter. Those kinds of things.
So we went to our corporate data warehouse, which is the VA’s big collection of data for all patients for many decades. We asked that question — how many people who turn out to be MRSA-positive on admission subsequently are found to have a multidrug-resistant gram-negative organism? And the answer was 44%. So that means that 44% of our patients who are swabbed [for MRSA] and put in isolation subsequently had a gram-negative [organism]. The odds of having a gram-negative culture were 2.5 times greater for those who screened [positive for MRSA]. So that, to us, was a benefit of doing MRSA swabbing. We really hadn’t intended going after other organisms. But this was a clear situation. When patients were isolated for MRSA, they were also being isolated for other organisms that could be a problem and which we weren’t looking for.
That was followed up by [another study] that took a look at what was going on with gram-negative bacteremias in the VA systems before and after the implementation of the MRSA prevention initiative in 2007. So essentially what [the researchers] found is that the rates of gram-negative bacteremias were going up steadily over time until 2007 when the MRSA initiative was enacted, and since then they have steadily gone down. It could be we were isolating patients accidentally, and for that reason there was less transmission of gram-negatives going on within facilities.
HIC: As you are well aware, some hospitals have gone to a more horizontal approach, emphasizing standard precautions and use of such measures as chlorhexidine bathing and mupirocin. Despite your obvious success, is this alternative approach something you may consider for certain pathogens and medical situations?
Evans: I think if you look at the VA program, the MRSA bundle is a four-part thing. The first one is active surveillance, which you might interpret being silo-like and vertical because it only focuses on MRSA. The second component is contact precautions, and as we’ve already talked about with the collateral-benefit paper you are probably putting a bunch of people into isolation who have gram negatives as well. You don’t know that because you are not looking for them, but you are getting the benefit of doing that. So that is more of a horizontal thing, since it is not strictly MRSA and affects other organisms as well.
The third component of our MRSA program is hand hygiene, and you can’t say that is not a horizontal approach. Then the fourth one is a culture transformation where infection control becomes everyone’s business. I would also interpret that as being horizontal. It's kind of like throwing a stone in a pond — the ripples that we get just because of the MRSA program. We just have to be careful about thinking of the MRSA prevention initiative as being only silo and vertical, because it is anything but that.
HIC: What about the movement by some hospitals to drop contact precautions for MRSA?
Evans: Some [hospitals] have stopped contact precautions and tracked their hospital infections over time and found no change [in infection rate]. So the conclusion is that you don’t really need to do contact precautions for MRSA if you’re doing really good hand hygiene and these other horizontal-type things.
I just want to throw out a word of caution. My concern is about these studies — the ones that look at what happens while the patient in the hospital. The patient is admitted, and theoretically they are not colonized with MRSA. So they do not go into contact precautions. Then if [the patient gets] colonized with the organism, it takes a little bit of time to develop a hospital-acquired infection. The length of stay for most patients is like 5 to 7 days.
There is the possibility that patients acquire the organism while in-house and they develop an infection, but it does not appear until after discharge. In our own data within the VA, we are finding that a portion of MRSA infections occur within 30, 60, or 90 days [post-discharge].
There is a large portion of those that occur in that time frame, and ostensibly they were from picking up the organism while in-house. In individuals who get colonized, their infections tend to appear after discharge. So when people study, write, and report that they stopped contact precautions and nothing happened, it well could be because their observation interval is too short. They don’t pick up the infections that occur because they occur after discharge.
- Evans ME, Kralovic SM, Simbartl LA. Eight years of decreased methicillin-resistant Staphylococcus aureus health care-associated infections associated with a Veterans Affairs prevention initiative. Am J Infect Control 2017; 45:13–16.
- Simbartl LA, Jain R, Roselle GA. Collateral benefit of screening patients for methicillin-resistant Staphylococcus aureus at hospital admission: Isolation of patients with multidrug-resistant gram-negative bacteria. Am J Infect Control 2015; 43:31-34.