Transcript New Hope for Prevention & Control of MRSA Infectns

Surprising Victories Against Old
Foes: New Hope for Prevention
and Control of HealthcareAssociated 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?
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):2014-2020, 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 healthcareassociated 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?
Emerging Prevalence of MethicillinResistance Among S. aureus in
U.S. Intensive Care Units
70
% Resistant
60
50
40
30
20
10
0
1975 1979 1983 1987 1991 1995 1999
National Nosocomial Infections Surveillance (NNIS)
System
Rationale for Efforts to Prevent and
Control Resistant Gram-positive Bacteria
• Emerging as dominant pathogens in
healthcare-associated infections
– for example:
• Between 1992-2002, 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; 20:408-411
Cheng et al J Hospital Infect 1988;12:91-101
Stosor et al. Arch Intern Med 1998; 158:522-527
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; 282:1745-1751
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 MethicillinResistance Among S. aureus in
U.S. Intensive Care Units
70
% Resistant
60
50
40
30
20
10
0
1960 1967 1974 1981 1988 1995 2002
USA
Emerging Prevalence of MethicillinResistance Among S. aureus in
U.S. Intensive Care Units
70
% Resistant
60
50
40
30
20
10
0
1960 1967 1974 1981 1988 1995 2002
USA
Denmark
Methicillin-resistant Staphylococcus
aureus in Europe, 1999–2002
Tiemersma et. al. Emerg Infect Dis 2004;10:1627-34
Methicillin-resistant Staphylococcus
aureus in Europe, 1999–2002
Tiemersma et. al. Emerg Infect Dis 2004;10:1627-34
Can the experience in other
countries be reproduced here?
MRSA Infection Incidence by Fiscal Year,
4W Unit, Pittsburgh VA, Oct 1999-Present
Infections per 1000 pt days
Intervention
2
1.5
1
0.5
0
2000
2001
2002
2003
2004
Overall Rates
Pre-intervention = 1.48 infections/1,000 pt days
Post-intervention = 0.68 infections/1,000 pt days
54% reduction, p=.04
MRSA Infection Incidence by Year,
Medical ICU Hospital B, 2001-Present
Infections per 1000 pt days
Intervention
4
3
2
1
0
2001
2002
2003
Overall Rates
Pre-intervention = 3.82 infections/1,000 pt days
Post-intervention = 1.62 infections/1,000 pt days
58% reduction, p<.01
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