Surprising Victories Against Old Foes: New Hope for Prevention and Control of Healthcare- Associated MRSA Infections John A. Jernigan, MD, MS Division of Healthcare Quality Promotion Centers for Disease Control and Prevention Atlanta, Georgia

What is the Preventable Fraction of Healthcare Associated Infections?

SENIC study results others

What is the Preventable Fraction of Healthcare Associated Infections? Some may have interpreted these data to mean that most healthcare associated infections are inevitable What impact has this had on the Psychology of prevention? How has this impacted how infection control programs operate?

Eliminating catheter-related bloodstream infections in the intensive care unit Berenholtz, S et al. Critical Care Medicine. 32(10): , October 2004.

Maybe the Preventable Fraction is Much Larger than we Thought? Healthcare Epidemiologists have been afraid of using the “E” word (elimination) with regard to healthcare- associated infections, but recent successes suggest that perhaps we should have been using it more.

Are such goals appropriate for the problem of antimicrobial resistance, with MRSA as a starting point?

National Nosocomial Infections Surveillance (NNIS) System Emerging Prevalence of Methicillin- Resistance Among S. aureus in U.S. Intensive Care Units

Rationale for Efforts to Prevent and Control Resistant Gram-positive Bacteria Emerging as dominant pathogens in healthcare-associated infections –for example: Between , among infections following CABG, cholecystectomy, colectomy, and total hip replacement, % S. aureus 16.6% -30.9% % S. aureus infections attributable to MRSA increased from 9.2% to 49.3% Treatment options are limited and less effective, may result in higher morbidity and mortality –Gonzalez Clin Infect Dis 1999;29:1171 –Lucas Clin Infect Dis 1998;26:1127 –Abramson ICHE 1999; 20: –Cheng et al J Hospital Infect 1988;12: –Stosor et al. Arch Intern Med 1998; 158:

Summary of Unadjusted Results of Studies Comparing Mortality of MRSA and MSSA Bacteremia Cosgrove et al. Clinical Infectious Diseases 2003:36;53-59

Rationale for Efforts to Prevent and Control Resistant Gram-positive Bacteria Prevalence of resistance leads to unfavorable antibiotic prescribing, and leads to more resistance –prevalent MRSA more glycopeptide use more glycopeptide resistance

MRSA infections add to the total S. aureus infection rate –Stamm Am J Infect Control 1993;21:70 –Boyce J Infect Dis 1993;148:763 –Chaix JAMA 1999; 282: –Jernigan ICHE 1995;16:686 –Harbarth J Hosp Infect 2000:46;43 Therefore, preventing MRSA infections should result in decreased S. aureus infection rates

“Okay, so MRSA and antimicrobial resistance in general are important problems, but they are different from bloodstream infections. It’s okay to set bold goals for preventing bloodstream infections, but we could never hope to be so successful against MRSA infection! Could we?”

Emerging Prevalence of Methicillin- Resistance Among S. aureus in U.S. Intensive Care Units

Emerging Prevalence of Methicillin- Resistance Among S. aureus in U.S. Intensive Care Units

Methicillin-resistant Staphylococcus aureus in Europe, 1999–2002 Tiemersma et. al. Emerg Infect Dis 2004;10:

Can the experience in other countries be reproduced here?

Overall Rates Pre-intervention = 1.48 infections/1,000 pt days Post-intervention = 0.68 infections/1,000 pt days 54% reduction, p=.04 Intervention

Overall Rates Pre-intervention = 3.82 infections/1,000 pt days Post-intervention = 1.62 infections/1,000 pt days 58% reduction, p<.01 Intervention

Huang, S. IDSA 2005

There are a growing number of studies suggesting that US healthcare facilities can successfully prevent MRSA infections

A regional collaborative approach may be a good way to approach the MRSA problem: –Sharing of MRSA-carriers between facilities –Success at the community level may be more readily accepted as generalizable –Need to agree on common system for measuring outcome, but there is room for alternative approaches to prevention. One size may not fit all. –Successes can be shared and spread across the community

Summary We (healthcare epidemiologists) may have badly underestimated the preventable fraction of healthcare-associated infections Regional/community collaboratives have been effective in achieving major reductions in healthcare-associated infections MRSA is an important patient safety issue that needs addressing.

Summary (continued) MRSA infections can be prevented, even in endemic settings Regional collaboration on MRSA prevention may have particular advantages. Successful MRSA prevention across a region would represent a major advance for infection control, and would have implications for control of other antimicrobial resistant infections