Infections due to antibiotic resistant organisms (ARO) are a major threat to public health worldwide and
a significant cause of healthcare-associated infections (HAI). AROs are especially threatening to
immunocompromised patients in intensive care units (ICUs), where a weakened immune system combined
with cancer chemotherapy and antibiotic exposures results in increased risk for HAIs due to AROs. A potential
source of ARO transmission is the hospital environment. AROs can survive on objects and surfaces in the ICU
for prolonged time intervals, resulting in fixed reservoirs for ongoing ARO transmission to vulnerable patients.
To create and optimize infection prevention strategies, it is crucial to understand the link between the hospital
environment and HAIs, and to optimize environmental hygiene intervention strategies to prevent HAIs due to
To characterize the environmental areas with the greatest ARO burden in the ICU, our group cultured,
identified, and created a biospecimen repository of 1,109 potential AROs from collected from ICU surfaces,
patient fecal samples, and clinical bloodstream infection (BSI) isolates from patients admitted to the bone
marrow transplant (BMT) ICU. Our preliminary selective microbiologic culture techniques and whole genome
sequencing (WGS) data indicate that there is a genetic link between AROs isolated from sink drains and
clinical BSI isolates. This raises the hypothesis that AROs in sink drains are being transferred between the ICU
environment and patients (or vice-versa), and that the environment may be a reservoir for ARO transmission.
Based on these preliminary data, our goal is to define the link between AROs found in the ICU environment
and patients with HAIs, and to design and test interventions to reduce the burden of AROs in the ICU
In this project, we will utilize antimicrobial susceptibility testing and WGS to longitudinally determine the
presence and transmission of AROs across the hospital environment, and determine the genetic link between
these strains to those causing BSIs in patients in a BMT ICU. Further, we will implement and measure the
impact of a bleach and hydrogen peroxide-based environmental hygiene intervention on the concentration of
AROs present in ICU sink drains. Completion of these specific aims will allow us to extensively characterize
the transmission dynamics of AROs across environmental surfaces and patients, and to evaluate an
environmental hygiene intervention that focuses on sink surfaces and drains.