Understanding the significance of microbiota recovered from health care surfaces

Microbial contamination of hospital surfaces remains despite adherence to routine disinfection. Our study demonstrates bioburden from various types of hospital high-touch surfaces and the pathogenicity of all bacteria recovered.

Several high-touch hospital surfaces from a single medical-surgical unit were sampled and cultured using replicate organism detection and counting (RODAC) Tryptic Soy agar plates. Colonies were then subcultured to blood agar plates and speciated using MALDI-TOF. The local microbiology laboratory database was queried for any clinical isolate match with the environmental samples recovered.

Manikins, bed rails, and workstations-on-wheels were the most contaminated surfaces with the largest variety of bacteria isolated from manikins and bed rails. A total of 60 different types of pathogens were isolated, 18 of which were well-known pathogens, and 7 were classified as important in the health care setting by CDC. Our clinical microbiology laboratory identified 29 of 60 hospital surface bacteria in clinical isolates. Urine, soft tissue, and blood were the most common sources of clinical isolates.

Surfaces in the health care environment harbor both well-known and not-so-well-known human pathogens. Several not-so-well-known pathogens are skin flora or environmental bacteria, which in the right setting, can become pathogenic and cause diseases including meningitis, brain abscess, endocarditis, and bacteremia.