Battling ESBL-E With Standard Precautions

Isolation precautions are the bread and butter for infection prevention efforts in health care. Using these measures can halt the spread of infection and ensure the safety of health workers and patients alike. These prevention strategies become increasingly important in the presence of resistant organisms, like extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E). Studies have shown at that ESBL-E carriers are relatively common, in a Spanish study, 7.69% of patients were carriers on admission.

More recently, though, the efficacy of contact precautions for such organisms has been called into question. Just how likely is ESBL-E to spread if good hand hygiene and standard precautions are utilized? A new research study sought to evaluate contact isolation versus standard precautions in non-critical care areas to assess the transmission of ESBL-E.

Across 4 European university hospitals, the team performed a cluster-randomized crossover trial in medical, surgical, or hybrid units without critical care patients. The authors noted that “Randomization was done via a computer-generated sequence, with a block size of 2 consecutive wards. Only laboratory technicians and data analysts were masked to allocation. Patients were screened for ESBL-E carriage within 3 days of admission, once a week thereafter, and on discharge.” Moreover, they defined the primary outcome as the incidence density of ESBL-E (per 1000 patient-days at risk).

Twenty hospital wards were enrolled, across 4 hospitals in Germany, the Netherlands, Spain, and Switzerland. The study period was from January 6, 2014 to August 31, 2016, which involved 38,357 patient admissions. Over 15,000 patients had a hospital stay longer than a week and of those, 11,368 patients (75%) were screen at least twice. Following these efforts, they found that the incidence density of hospital-acquired ESBL-E was 6 per 1000 patient-days at risk during periods of contact precautions and 6.1 during periods of standard precautions (P = 0.9710).

These findings were particularly interesting as the notion of contact precautions has been engrained in infection prevention efforts for decades. The authors ultimately note that in their study, contact isolation revealed no benefits when used in addition to standard precautions in efforts to control the spread of ESBL-E in non-critical care units.

The distribution of ESBL-E patients in these areas might be different though and it is important to note that this is only assessing one organism. It does raise several questions, though, from the infection prevention standpoint, regarding the utility of contact precautions. For those patients with active infections, contact precautions are important however, what about colonization?

There has long been discussion regarding the continuation of contact precaution in those patients considered colonized or without active infection. Isolation precautions inherently impact the patient’s satisfaction during their hospital stay as health care workers often visit those patients less.

This study has shed light on the limitations of contact precautions and that vigilant standard precautions might prove effective against multi-drug resistant infections like ESBL-E. Future efforts should be made to continue these studies and assess the efficacy against resistant infections. Moreover, there is a renewed need to assess contact precaution efficacy in terms of infection control failures, like poor use of gowns, lack of hand hygiene before or after glove use, and more.