Superbug CRE may endure in patients one year after initial infection: study


Patients who tested positive for carbapenem-resistant Enterobacteriaceae (CRE) took an average of 387 days following hospital discharge to be clear of the organism, according to a new study published in the March issue of the American Journal of Infection Control, the official publication of the Association for Professionals in Infection Control and Epidemiology (APIC). 

The study was conducted in the Shaare Zedek Medical Center, a 700-bed university-affiliated general hospital in Jerusalem, Israel. The research team analyzed follow-up cultures from 97 CRE-positive patients who had been discharged from the medical center between January 2009 and December 2010.  

The average time until cultures became negative was 387 days. At three months, 78 percent of patients remained culture positive; at six months, 65 percent remained positive; at nine months, 51 percent, and at one year 39 percent of patients remained positive, meaning they could potentially become re-infected or transmit the germ to others. 

Risk factors for extended carriage included the number of hospitalization days, whether and how often the patient was re-hospitalized, and whether the patient had an active infection as opposed to colonization without signs of active disease. 

This is one of the first studies to determine length of CRE duration after hospital discharge and provides vital insight into treating formerly CRE-positive patients upon readmission as to limit the spread of this virulent and often deadly pathogen. 

The authors state, “Patients with multiple hospitalizations or those who were diagnosed with clinical CRE disease should be assumed to have a more extended duration of CRE coverage and should therefore be admitted under conditions of isolation and cohorting until proven to be CRE-negative. These measures will reduce the hospitalization of CRE-positive patients among the general patient population, potentially preventing the spread of CRE.”

CRE are extremely difficult-to-treat, multidrug-resistant organisms that are emerging in the United States. A CRE strain of Klebsiella pneumoniae recently spread through the National Institutes of Health hospital outside Washington, DC, killing six people. Because of increased reports of these multidrug-resistant germs, the Centers for Disease Control and Prevention recently alerted clinicians about the need for additional prevention steps to prevent transmission.

Full text of the article is available to journalists upon request; contact Liz Garman, APIC, 202-454-2604, egarman@apic.org to obtain copies.


AJIC: American Journal of Infection Control (www.ajicjournal.org) covers key topics and issues in infection control and epidemiology. Infection preventionists, including physicians, nurses, and epidemiologists, rely on AJIC for peer-reviewed articles covering clinical topics as well as original research. As the official publication of APIC, AJIC is the foremost resource on infection control, epidemiology, infectious diseases, quality management, occupational health, and disease prevention. AJIC also publishes infection control guidelines from APIC and the CDC. Published by Elsevier, AJIC is included in MEDLINE and CINAHL.


APIC’s mission is to create a safer world through prevention of infection. The association’s more than 14,000 members direct infection prevention programs that save lives and improve the bottom line for hospitals and other healthcare facilities. APIC advances its mission through patient safety, implementation science, competencies and certification, advocacy, and data standardization. Visit APIC online at www.apic.org. Follow APIC on Twitter: http://twitter.com/apic.    


“Duration of carriage of carbapenem-resistant Enterobacteriaceae following hospital discharge” by Frederic S. Zimmerman, Marc V. Assous, Tali Bdolah-Abram, Tamar Lachish, Amos M. Yinnon and Yonit Wiener-Well appears in the American Journal of Infection Control, Volume 41, Issue 3 (March 2013). 


Frederic S. Zimmerman, BSc 

Infectious Disease Unit, Shaare Zedek Medical Center

Hebrew University-Hadassah Medical School, Jerusalem, Israel


Marc V. Assous, MD, PhD 

Laboratory of Clinical Microbiology and Immunology, Shaare Zedek Medical Center 


Tali Bdolah-Abram, MSc 

Hebrew University-Hadassah Medical School, Jerusalem, Israel


Tamar Lachish, MD

Infectious Disease Unit, Shaare Zedek Medical Center


Amos M. Yinnon, MD (Corresponding Author)

Infectious Disease Unit & Division of Internal Medicine, Shaare Zedek Medical Center

Hebrew University-Hadassah Medical School, Jerusalem, Israel


Yonit Wiener-Well, MD

Infectious Disease Unit, Shaare Zedek Medical Center,

Hebrew University-Hadassah Medical School, Jerusalem, Israel




Contact Info

Liz Garman