Epicenters for the Prevention of Healthcare Associated Infections (HAIs) -- Volume of Contamination and Nosocomial Infection Control: Specific Aim II.1

We will perform a two-armed pilot test among 40 front-line healthcare workers (nurses, doctors, respiratory therapists, etc) at the University of Iowa Hospitals and Clinics. Participants will serve as their own controls. First, participants will perform hand hygiene with alcohol-based hand rub as they normally would in clinical practice then don PPE. We, the research team, will contaminate participating healthcare workers' (HCW) PPE with either bacteriophage MS2 (twenty participants) or S. marcescens ATCC 14756 (twenty participants). MS2 preparation and propagation and S. marcescens culture suspensions will each be performed as previously described. The MS2 bacteriophage will be suspended in 0.01 M phosphate-buffered saline and each PPE site will be contaminated with 10^5 plaque-forming units (PFU) of MS2 in 5 drops of 5 μL each. Aliquots of 3 mL of S. marcescens broth suspension (yielding bacterial titers of ~1 X 10^9 CFU/ml) will be applied to each PPE site. Participants will then doff PPE using the Centers for Disease Control's (CDC) recommended protocol. We will sample their hands using the bag broth method. A research assistant will monitor participants as they wash their hands with soap and water then rinse their hands with 70% ethanol. Participants will then apply ProvodineTM to their hands and put on (don) fresh PPE. We will repeat the contamination, doffing, and sampling procedure. For MS2 recovery, we will assay the eluent using the most probable number (MPN) enrichment infectivity assay. For S. marcescens recovery, we will dilute the eluent, plate it, incubate the plates, and count the colonies as described.