1. CRE Surveillance and Prevention
Cody Loveland, MPH
Surveillance Epidemiologist
Wyoming Department of Health

2. Learning Objectives
Upon completion of this presentation, attendees will be able to:
1.    Understand the clinical significance of CRE and its modes of transmission
2.    Identify and describe the WDH CRE definition
3.    Describe 12 facility-level CRE prevention strategies
4.    Evaluate your facility’s readiness for detecting, reporting, and containing CRE

3. CRE Basics

4. CRE = Carbapenem-Resistant Enterobacteriaceae
Family of bacteria - Enterobacteriaceae
Normal part of human gut flora
Carbapenems are broad spectrum antibacterial drugs
Imipenem, meropenem, doripenem, ertapenem
Often treatment of last choice for gram-negative bacteria
CRE are bacteria that have developed resistance to carbapenems
Either through susceptibility testing or through the production of carbapenemase

5. Family of Enterobacteriaceae
Medically Important CRE
Klebsiella pneumoniae
Enterobacter species
Escherichia coli
Klebsiella oxytoca
Salmonella enterica
Serratia marcescens
Citrobacter freundii

6. Why are CRE Important?

7. Mortality in CRE Bacteremia
p<0.001
Patel et al. Infect Control Hosp Epidemiol 2008;29:

8. Not just a hospital problem
Matters for whole healthcare system
Shared healthcare providers
Patient and resident transfers
Mode of transmission
Person-to-person
Especially contact with wounds or stool
Contaminated medical equipment

9. Mechanisms of Resistance
Carbapenemase Producing (CP-CRE)
enzyme that breaks down Carbapenems
KPC (most common)
NDM
OXA-48
VIM
IMP
Others??
These are an infection control emergency!
Non-Carbapenemase Producing, but resistant (Non-CP-CRE)

10. WDH CRE Definition
The Wyoming Department of Health defines CRE as any Enterobacteriaceae that:
Are resistant to at least one carbapenem (including imipenem1, meropenem, doripenem, or ertapenem) using the current M100-S25 CLSI breakpoints2; OR
Test positive for carbapenemase production by the Carba NP test;
Test positive for a known carbapenemase gene by nucleic acid amplification testing.
1, 2 See WDH CRE Toolkit p. 3. Available at

11. Sample CRE Lab Result This is a non-CP-CRE
Susceptibility Results (WDH Def. part 1)
Whether sample produces carbapenemase (WDH Def. Part 2)
Results of NAAT Testing (WDH Def. Part 3)
Genus and species

12. Other Carbapenem-Resistant Organisms
Pseudomonas aeruginosa and Acinetobacter baumannii species are not part of the Enterobacteriaceae family and therefore are not technically considered CRE.
HOWEVER, still medically important and drug resistant!
Often contain same carbapenemase genes as CRE
Send CR-PA and CR-AB samples to WPHL for confirmation testing!
Only send non-mucoid CR-PA samples
Follow same prevention principles as CRE, but also consult with WDH

13. Colonization vs. Infection
Colonization – The presence of bacteria on a body surface (like on the skin, mouth, intestines or airway) without causing disease in the person.
CRE colonization can be prolonged (>6 months)
Can lead to unidentified transmission
Infection – The presence of bacteria on the body that is associated with an immune response.
Both statuses have different implications in the healthcare setting and impact your response
Infected Patients
Colonized
Patients
Created by Uwe Kils (iceberg) and User:Wiska Bodo (sky). [GFDL ( or CC-BY-SA-3.0 ( via Wikimedia Commons

14. Non-CP-CRE Colonization††
Measure
CP-CRE Infection
CP-CRE Colonization
Non-CP-CRE Infection
Non-CP-CRE Colonization††
Notify Receiving facility
Yes
Notify WDH upon transfer or death No
Standard Precautions
Contact Precautions†
Gown/gloves for in-room resident care
For residents at higher risk of CRE transmission
Door Signage
Private Room
Yes (strongly encouraged)
Restricted to room
No**
Enhanced Environmental Cleaning
Designated or disposable equipment
If >1 case, cohort staff if feasible
Optional
If >1 case, cohort residents if feasible
Consult with WDH regarding screening cultures
Visitor recommendations:
Perform hand hygiene often, particularly after leaving the resident’s room.
Gown/gloves if contact with body fluids is anticipated.
Gown/gloves if no contact with body fluids is anticipated.   

15. Facility-Level Prevention Strategies

16. Facility-Level Prevention Strategies
1. Hand Hygiene
Single most important aspect of preventing CRE transmission!
Reminders, education, audits

17. Facility-Level Prevention Strategies
2. Contact Precautions
In acute care and ventilator units of skilled nursing facilities:
Perform hand hygiene
Donning gown and gloves before entering patient’s room
Removing the gown and gloves and performing hand hygiene before exiting the affected patient’s room
Lower-acuity post-acute setting:
Depends on procedures and perceived risk

18. Facility-Level Prevention Strategies
3. Education
Need to educate HCP about preventing transmission of CRE
At minimum, education should include reviews of proper use of contact precautions and proper donning and doffing of PPE so HCP don’t expose themselves
Consider giving in-service to staff on CRE and other gram-negative MDRO
MDR-Klebsiella pneumoniae
Photo credit: David Dorward; Ph.D.; National Institute of Allergy and Infectious Diseases (NIAID)

19. Facility-Level Prevention Strategies
4. Use of Devices
Device use has been associated with CRE
Minimizing device use should be part of effort to prevent all MDROs
Regularly review device use to ensure it’s still required and promptly discontinue use when no longer needed
5. Laboratory Notification
Need protocol in place to notify proper clinical and IP staff in a timely manner (i.e. within 4 to 6 hours)
True for facilities with both on-site and off-site laboratories

20. Facility-Level Prevention Strategies
6. Inter-facility Communication
CRE infection/colonization shouldn’t preclude transfers
Facilities transferring patients colonized or infected with CRE must notify the receiving facility of the patient’s CRE status
Notify about invasive devices the patient has and the duration of any ongoing antimicrobial therapy
Identification of CRE Patients at admission
Need a mechanism to identify patients colonized or infected with CRE at re- admission so the appropriate infection control precautions can be initiated

21. Facility-Level Prevention Strategies
7. Antimicrobial stewardship
Multiple antimicrobial classes have been shown to be a risk for CRE colonization and/or infection
Active antimicrobial stewardship program
8. Environmental Cleaning
Once CRE patients are discharged, terminal cleaning of CRE patient rooms should be performed.

22. Facility-Level Prevention Strategies
CRE
Patient w/o CRE
9. Patient and Staff Cohorting
Patients colonized or infected with CP-CRE should be housed in single patient rooms.
If insufficient numbers of rooms, give preference to patients at highest risk of transmission (incontinent, uncontrolled draining wounds, medical devices)
Consider a dedicated staff that provide the bulk of patient’s care. The specific staff that are dedicated may vary depending on the healthcare setting.
Not generally recommended for single patients, but in high prevalence areas and during outbreaks.

23. Facility-Level Prevention Strategies
10. Screening Contacts of CRE Patients
Screening process for CRE is rectal or peri-rectal swabs
Screen patient with epidemiologic links to unrecognized CP-CRE colonized or infected patients
Should be done even if patient has been discharged – consult with WDH!

24. Facility-Level Prevention Strategies
11. Active Surveillance Testing
Clinical cultures identify only a minority of patients colonized with CRE and unrecognized colonized patients who are not on contact precautions may be a source of CRE transmission.
Screen high-risk patients at admission or at admission and periodically during their facility stay for CRE (during outbreaks)
Consider surveillance cultures for patients admitted overnight to healthcare setting in foreign country within last 6-12 months, or within the US in an area with high CP-CRE prevalence.

25. Facility-Level Prevention Strategies
12. Chlorhexidine Bathing
Used successfully to prevent certain types of HAIs and to decrease MDRO colonization in ICUs.
Bathe patients daily with 2% liquid chlorhexidine or 2% chlorhexidine wipes
Usually high risk settings (ICUs)
Do not use above the jaw line or on open wounds
In LTC, may be used on targeted high-risk residents or high-risk settings (i.e. ventilator unit).

26. Facility CRE Readiness Evaluation

27. CRE Readiness Questions to Ask in Your Facility
Does your lab and/or reference lab test for CRE?
What CLSI standards are they using?
Can they test for Carbapenemase production?
What indicators prompt them to suspect a CRE? Positive ESBL? Ceftazidime or Ceftriaxone resistance?
If my lab cannot perform carbapenemase testing, what will be the infection control response protocol while we wait for confirmatory results?

28. CRE Readiness Questions to Ask in Your Facility
What is the timeframe in which you want to be notified for a CRE?
How will the lab notify the IP staff and clinicians of a positive?
Will they notify you if they suspect a positive before it’s identified?
Make sure they still notify you and report to public health if the sample is Carbapenem resistant, but susceptible to a more first-line drug!
Are our notification systems and protocol set up in a way that everything can be implemented properly (i.e. initiating precautions, communicating CRE status at transfers) if you (the IP) are gone?

29. CRE Readiness Questions to Ask in Your Facility
Do we have a system in place to flag patients with CRE at re-admission?
Is this something our EMR can handle?
Do I need to talk to IT staff about setting this up?
Will our administration support this as a priority? Who can be a champion to help administration understand this should be a priority?
Do we have a procedure upon intake to identify potentially infectious people (especially nursing homes)?
If the patient is transferred, how will you notify the receiving facility?
Do NOT assume that just because it is in the chart, they have read it.
Who will be responsible for making sure this notification is clear?
Don’t forget to notify medical transport

30. CRE Readiness Questions to Ask in Your Facility
What is my system for tracking CRE in my facility?
Line list? EMR? MS Access Database? NHSN?
Is my system capable of tracking patient risk factors?
Can I come back and review former cases to identify trends?

31. Resources

32. Questions? cody.Loveland@wyo.gov 307-777-8634