Hospital Authority Convention 2007
Control of Methicillin-ResistantStaphylococcus Aureus
in a Chest Hospital
Dr. KC Wong 1,2, Ms. SM Ling 2, Dr. YC Chan1, Ms. MC Chan 21Tuberculosis and Chest Unit2Infection Control TeamTWGHs Wong Tai Sin Hospital8th May 2007
Introduction (1)
- Methicillin-resistant Staphylococcus aureus (MRSA) first isolated in UK in 1961
- An important nosocomial pathogen in hospitals worldwide
- Individual infection & infection outbreak
Introduction (2)- MRSA endemic in local hospitals- Highly prevalent at Wong Tai Sin Hospital:
*Department of Rehabilitation and Extended Care*Tuberculosis and Chest Unit
- Preponderance of chronic patients: poor functional status, dependent ADL, increased LOS, antibiotic therapy and prior hospitalization last 3-6/12
Control of MRSA Important (1)- Substantial morbidity and mortality of
nosocomial MRSA infections- Potential threats of more resistant pathogen:
* Vancomycin Intermediate Staphylococcus aureus (VISA)
* Vancomycin Resistant Staphylococcus aureus (VRSA)
- First VISA identified in 1995
Control of MRSA Important (2)
- Limited number of antibiotics available for treatment
- Costs of treatment of MRSA infections & implementation of infection control measures
- Linezolid: newer effective antibiotic, unit cost more than 20 x Vancomycin
Infection Control IcebergMRSA isolates from clinical specimens
Cross Transmission
Asymptomatic patients with unrecognized colonization of MRSA
Nursing Home Patients
Transfers
Readmission
New Infection Control Policy in 2001 (1)(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
- Active surveillance and immediate “isolation” of high risk patients for MRSA on hospital re-admission(Targeted surveillance culture & pre-emptive “isolation”)
- High risk patients defined as patients known to have MRSA in previous admission
New Infection Control Policy (2)(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
- Evidence-based guideline by Society for Healthcare Epidemiology of America (SHEA): Similar policy of active surveillance cultures (ASC) for patients at high risk for carriage for MRSA (Infection Control & Hospital Epidemiology, May 2003)
New Infection Control Policy (3)(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
- Management of Multidrug Resistant Organisms in Healthcare Settings 2006 (HICPAC, Centre for Disease Control & Prevention) : ASC also recommended
- Papia et al. Patients with previous Hx of MRSA colonization much more likely to be MRSA screening positive on re-admission (OR, 13.1, P:0.05) [Infection Control & Hospital Epidemiology, July 1999]
Containing the Iceberg(Targeted Surveillance & Pre-emptive “isolation” on Re-admission)
NosocomialMRSAInfectionMRSAColonization
MRSA isolates from clinical specimens
Asymptomatic patients with unrecognized colonization of MRSA
Active Surveillance & immediate “Isolation” (1)
- A continuously updated master name-list of all patients known to have MRSA in previous hospitalization(s) is compiled by Infection Control Team
- Hospital admission officer checks for history of MRSA by this master name-list against the scheduled daily admission
Active Surveillance & immediate ”Isolation” (2)
- Active surveillance cultures & pre-emptive application of contact precautions in patients known to have MRSA in previous hospitalization(s), immediately upon hospital re-admission
- Screening cultures: anterior nares, bed-sores and previous body sites of MRSA isolate
Annual MRSA Incidence 1998 -2005(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
Year Incidence of New MRSA Patient per 1,000
Admission p-value#
1998 16.66 -
1999 11.06 -
2000 12.68 -
Average of 1998 - 2000 (Reference)
13.14 -
2001 Active surveillance and immediate isolation of patients high risk for MRSA re-admission
2002 10.99 0.255
2003 7.98 0.03
2004 7.33 0.003
2005 7.81 0.006
Average of 2002 - 2005 8.71 < 0.001
# Testing the incidence rate of each year against the reference (average of 1998 - 2000).
MRSA Screening Patients(Wong Tai Sin Hospital)
No. of new MRSA Patients No. of MRSA patients re-admitted WTSH
Year WTSH acquiredOther Hospitals
acquired Total +ve Screening -ve Screening Total
2000 148(70%) 64(30%) 212 - - -
2001 125(55%) 104(45%) 229 - - -
2002 174(66%) 89(34%) 263 14(50%) 14(50%) 28
2003 99(61%) 63(39%) 162 20(71%) 8(29%) 28
2004 134(62%) 82(38%) 216 39(61%) 25(39%) 64
2005 116(50%) 118(50%) 234 60(52%) 56(48%) 116
1. MRSA screening began in 2001 in Tuberculosis & Chest Unit
2. MRSA screening in whole hospital since 2004
3. SARS outbreak in 2003
Milestones of MRSA Control (1)(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
1999 * Infection Control Link Nurses
2001 * Policy of “Active surveillance & immediate ‘isolation’ of high riskpatients for MRSA on hospital re-admission”
Milestones of MRSA Control (2)(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
2003 * Post-SARS outbreak: - 6-bed cubicles; 4-bed, 2-bed and
single isolation rooms withindependent ventilation
- 3-feet spatial separation betweenbeds
Milestones of MRSA Control (3)(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
2004 * Advocate use of alcohol-based hand rub for hand anti-sepsis
* Policy of “Active surveillance & immediate ‘isolation’ of high risk patients for MRSA on re-admission endorsed / implemented for the whole hospital
0
5
10
15
20
1998 1999 2000 Ave ra ge of
1998 - 2000
2001 2002 2003 2004 2005 Ave rage of
2002 - 2005
Per 1 ,000 admission
Annual Incidence MRSA 1998 – 2005(Tuberculosis & Chest Unit, Wong Tai Sin Hospital)
ICLNs
Active surveillance & pre-emptive isolation of patients high risk for MRSA on re-admission
Post SARS isolation facilities
Alcohol-based hand rub
P=0.
030
P=0.
255
P=0.
003
P=0.
006
P<0.
001
Ref
eren
ce
Annual MRSA Incidence 1998 -2005(Department of Rehabilitation & Extended Care,
Wong Tai Sin Hospital)
Year Incidence of New MRSA Patient per 1,000 Admission
1998 26.00
1999 22.27
2000 25.37
2001 20.97
2002 28.41
2003 26.48
#2004 28.75
2005 23.16
# Policy of "Active surveillance & immediate ‘isolation’ of high risk patients in hospital re-admission " implemented since 2004
Conclusions
- Active surveillance & pre-emptive “isolation” of high risk patients contribute to MRSA control even in endemic wards
- Our experiences concur with what are reported in literature
Thank you for your attention