1. CNISP & CIHI MRSA infection rate comparison Preliminary results
May

2. What is the Canadian Nosocomial Infection Surveillance Program (CNISP) ?
CNISP is as a collaboration between PHAC (CCDIC and NML)and sentinel hospitals across Canada who participate as members of the Canadian Hospital Epidemiology Committee (CHEC), a subcommittee of the Association of Medical Microbiology and Infectious Disease (AMMI) Canada.
CNISP was established in 1994 as a hospital-based sentinel surveillance system
Objective: Report on rates and trends in national and regional hospital-associated infections (HAIs) including antimicrobial resistant organisms (AROs), strain types and resistance patterns, some of which have been identified by FPTs (CIDSC) as priorities for AMR surveillance
Currently CNISP collects surveillance data from 65 hospitals in 10 provinces
network of hospitals that has worked in partnership with PHAC/NML since 1994
ONLY national surveillance system in Canada collecting epidemiologic and linked microbiology data regarding HAI and ARO infections

3. Current CNISP surveillance projects
Methicillin Resistant Staphylococcus aureus (MRSA) infections
Vancomycin Resistant Enterococci (VRE) infections
Hospital-associated Clostridium difficile Infection (CDI)
Central line associated bloodstream infections (CLABSI) (also collects antimicrobial resistance data)
Carbapenem-Resistant Gram-Negative (CRGN) (Enterobacteriaceae & Acinetobacter)
Three surgical site infection (SSI) surveillance projects – all collecting antimicrobial resistance data
Hip & Knee SSI
Pediatric Cardiac SSI
Cerebrospinal fluid (CSF) shunt SSI
Antimicrobial Utilization data (Hospital pharmacies)
Periodic point-prevalence surveys of HAIs and antimicrobial utilization data – conducted in 2001, 2009 & 2017
Each CNISP surveillance project has a working group comprised of PHAC and CHEC members
Working groups direct the development, implementation and prioritization of surveillance projects including the development of case definitions

4. How CNISP works
CNISP surveillance follows a case identification process based on standardized case definitions, laboratory confirmation and chart review by infection control professionals. This method of surveillance is considered to be the gold standard in identifying cases of infection in any surveillance system.
CNISP surveillance provides key information that informs the CARSS report and international reports (WHO) and also assists in the development of federal, provincial, territorial and local infection prevention and control programs and policies
When carried out in a uniform manner, surveillance provides a measure of the burden of illness, establishes benchmark rates for internal and external comparison, identifies potential risk factors, and allows for the assessment of specific interventions

5. CNISP in Action
contributes to scientific literature - since 1995, CNISP has produced > 260 publications (scientific articles, reports, conference abstracts) providing scientific evidence to inform public health action to reduce HAIs
established and currently maintains only national surveillance system to determine epidemiology of HAI in Canadian hospitals and provides Canadian hospitals with “benchmark” data (national, regional and site-specific HAI rates, strain types and antimicrobial resistance and utilization data)
provides evidence-based data for CARSS and Canadian infection prevention and control guideline preparation
raises public awareness of important infection control issues relating to AROs and HAIs

6. 2015-2016 CNISP/CIHI data comparison
59 CNISP hospitals participated in CNISP MRSA surveillance
CNISP Québec hospitals (N = 6) excluded
7 of the CNISP hospitals compared are combined in the CIHI database
Therefore comparison is on 46 hospitals
Region
N (%)
Total patient days
April
March
# MRSA infections
(in-hospital only)
Rate per 10,000 patient days p
CNISP
CIHI
West
n = 22 (47%)
3,181,564
2,725,461
457
190
1.44
0.70
<0.001
Central
n = 14 (32%)
1,993,869
206
123
0.90
0.62
East
n = 10 (21%)
879,000
709,261
121 44
1.38
National
N = 46
6,359,793
5,428,591
784
357
1.23
0.66
West = BC, AB, SK, MB; Central = ON; East = NS, NB, NL, PEI

7. West Central East National
Region
# CNISP hospitals with
Pt days > CIHI
Pt days < CIHI
Pt days = CIHI
# infections
> CIHI
< CIHI
= CIHI
West
n = 22 (%)
21 (95%)
1 (5%)
16 (72%)
3 (14%)
Central
n = 14 (%)
14 (93%)
0 (7%)
14 (100%)
East
n = 10 (%)
6 (60%)
4 (40%)
9 (90%)
1 (10%)
National
N = 46
41 (87%)
5 (13%)
39 (85%)
3 (6%)
4 (9%)

11. With the release of their data, CIHI has agreed to post on their website the following message:
“The Public Health Agency of Canada (PHAC) produces healthcare-associated infection rates based on reporting from infection, prevention and control programs in 65 hospitals across Canada through the Canadian Nosocomial Infection Surveillance Program (CNISP). These rates are published at the regional (e.g. western, central, eastern) and national level. Comparisons of CIHI’s regional and national rates with CNISP rates of C. difficile and MRSA infection should be done with caution due to significant methodological differences:
- CIHI’s indicator captures C. difficile and MRSA infections in patients identified after admission to hospital (most likely hospital acquired); it is risk-adjusted using standardized diagnostic criteria.
- CNISP captures healthcare-associated C. difficile and MRSA infections (further categorized as healthcare or community associated) on all hospitalized patients using laboratory confirmation and standardized surveillance case definitions.
- CIHI's C. difficile and MRSA infections indicator is based on physician documentation of an active infection on patient charts, captured through ICD-10-CA codes in administrative data following the direction in the Canadian Coding Standards. Incomplete documentation of the type of infection in a patient chart may lead to an underestimation of infections within CIHI’s indicator.
- CNISP follows a case identification process based on standardized case definitions, laboratory confirmation and chart review by infection control professionals and constitutes active prospective surveillance.”