To assess the impact of an electronic surveillance system on isolation practices and rates of methicillin-resistant Staphylococcus aureus (MRSA).

A pre-post test intervention.

Inpatient units (except psychiatry and labor and delivery) in 4 New York City hospitals.

All patients for whom isolation precautions were indicated, May 2009–December 2011.

Trained observers assessed isolation sign postings, availability of isolation carts, and staff use of personal protective equipment (PPE). Infection rates were obtained from the infection control department. Regression analyses were used to examine the association between the surveillance system, infection prevention practices, and MRSA infection rates.

A total of 54,159 isolation days and 7,628 staff opportunities for donning PPE were observed over a 31-month period. Odds of having an appropriate sign posted were significantly higher after intervention than before intervention (odds ratio [OR], 1.10 [95% confidence interval {CI}, 1.01–1.20]). Relative to baseline, postintervention sign posting improved significantly for airborne and droplet precautions but not for contact precautions. Sign posting improved for vancomycin-resistant enterococci (OR, 1.51 [95% CI, 1.23–1.86]; P = .0001), Clostridium difficile (OR, 1.59 [95% CI, 1.27–2.02]; P = .00005), and Acinetobacter baumannii (OR, 1.41 [95% CI, 1.21–1.64]; P = .00001) precautions but not for MRSA precautions (OR, 1.11 [95% CI, 0.89–1.39]; P = .36). Staff and visitor adherence to PPE remained low throughout the study but improved from 29.1% to 37.0% after the intervention (OR, 1.14 [95% CI, 1.01–1.29]). MRSA infection rates were not significantly different after the intervention.

An electronic surveillance system resulted in small but statistically significant improvements in isolation practices but no reductions in infection rates over the short term. Such innovations likely require considerable uptake time.