Service Ready Ambulance Surfaces and Emergency Medical Services Clinicians are Routinely Contaminated with Clinically Important Pathogens.

OBJECTIVES: To characterize contamination of ambulances and emergency medical services (EMS) clinicians with clinically important pathogens (CIPs) before and after a shift. METHODS: Prospective observational study of 20 ambulances from two EMS agencies (10 nonemergency transport, 10 emergency 9-1-1) from September 2021 to March 2022. Samples were collected from patient-facing and clinician-facing surfaces, EMS uniforms, and right nostril before a shift and after a shift but prior to post-shift cleaning. Ambulance surfaces were disinfected by study staff after pre-shift sampling to establish a near-zero reference. The CIPs included methicillin-resistant and methicillin-sensitive Staphylococcus aureus (MRSA, MSSA), vancomycin-resistant Enterococcus (VRE), and Clostridioides difficile. The EMS clinicians completed surveys on hygiene behaviors and beliefs. Primary outcome was presence of ≥1 CIP at an individual sampling site. RESULTS: Across 20 ambulances and 27 EMS clinicians, 941 samples were collected. Overall, 18.5% harbored ≥1 CIP. MSSA was most common (12.8%), followed by MRSA (4.6%) and VRE (3.0%). Clostridioides difficile was rare (0.1%). When deemed service ready, 63.1% of EMS clinicians and 60% of ambulances had ≥1 CIP. Post-shift contamination remained similar (EMS clinicians 67.6%, ambulances 60%). Emergency 9-1-1 ambulances had higher contamination than nonemergency ambulances. EMS clinicians reported high awareness of the importance of clean uniforms and vehicles. CONCLUSIONS: EMS clinicians and ambulances harbor CIPs when deemed service ready and contamination accumulates during shifts. Pre-shift uniform contamination suggests clinicians may be sources of medical transport setting contamination. Improved uniform hygiene, rigorous terminal cleaning, and targeted interventions are needed to reduce medical transport-associated infection risk.

Duke Scholars

Author Deverick John Anderson Medicine, Infectious Diseases