The Role of Antibiotic-Resistant Bacteria in Healthcare-Associated Infections


An article in the Morbidity and Mortality Weekly Report from the Centers for Disease Control and Prevention (CDC) on March 3, 2016 discusses the most common healthcare-associated infections (HAIs), many of which are caused by antibiotic-resistant (AR) bacteria. This article highlights the incidence of these infections and emphasizes the continued need for HAI prevention to decrease adverse patient outcomes, namely sepsis and death. This report is the first to combine national data on major AR bacteria threats and progress on HAI prevention.

The following is a summary of the data presented in this article. A full reference for the original article, from which all information below is gathered, can be found at the conclusion of this post.


HAIs caused by AR bacteria are an international public health concern, as they significantly increase patient morbidity and mortality. Of the 18 urgent AR threats outlined in a 2013 CDC report, six (in addition to C. difficile infection, or CDI) are healthcare-acquired. The CDC assessed the role of these healthcare-acquired AR bacteria in common HAIs, specifically central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), and surgical site infections (SSIs). CLABSIs, CAUTIs, and SSIs, along with CDI, were responsible for 50% of all HAIs in acute care hospitals in 2011.


During 2014, the National Healthcare Safety Network collected data from 1135 inpatient rehabilitation centers, 501 long-term acute care hospitals, and 4000 short-term acute care hospitals in all 50 states, the District of Columbia, and Puerto Rico. For each type of HAI, national standardized infection ratios and percentage reduction from a baseline year were calculated by facility type.


When compared to baseline historic data from 5-8 years earlier, SSIs decreased by 17% and CLABSIs decreased by 50% in 2014. There was no significant percentage decrease in CAUTIs from baseline, though CDIs decreased by 8% in hospitals from 2011-2014.

Combining HAIs other than CDI across all settings, 47.9% of Staphylococcus aureus isolates were methicillin resistant (MRSA), 29.5% of enterococci were vancomycin-resistant (VRE), 17.8% of Enterobacteriaceae were extended-spectrum beta-lactamase phenotype (ESBLs), 3.6% of Enterobacteriaceae were carbapenem resistant (CREs). Additionally, 15.9% of Pseudomonas aeruginosa isolates and 52.6% of Acinetobacter species were found to be multidrug resistant. The likelihood of HAIs caused by any of the six resistant bacteria ranged from 12% in inpatient rehabilitation facilities to 29% in long-term acute care hospitals.



Although the incidence of HAIs has improved in the past several years, two million people continue to be affected on an annual basis, resulting in approximately 23,000 deaths per year. This study determined a high percentage of HAIs to be related to AR species; these findings are particularly relevant for the Gastroenterology community given significant concern about the transmission of CRE via duodenoscopes and the associated hospital outbreaks over the past year. In this vein, it is paramount that healthcare professionals adhere to HAI prevention methods, such as hand hygiene and proper sterilization of medical equipment, and commit to the practice of antimicrobial stewardship.


Weiner, L.M. et al. 2016. Vital Signs: Preventing Antibiotic-Resistant Infections in Hospitals – United States, 2014. Morbidity and Mortality Weekly Report, Centers for Disease Control and Prevention (