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Published on: February 22, 2019
A methodology for using Lambda phages as a proxy for pathogen transmission in hospitals
K B Burke1, B A Berryhill2, R Garcia3
1Department of Biology, Emory University, Atlanta, GA, USA; Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.
Background:
One major concern in hospitalized patients is acquiring infections from pathogens borne on surfaces, patients, and healthcare workers (HCWs). Fundamental to controlling healthcare-associated infections is identifying the sources of pathogens, monitoring the processes responsible for their transmission, and evaluating the efficacy of the procedures employed for restricting their transmission.
Aim:
To present a method using the bacteriophage Lambda (λ) to achieve these ends.
Methods:
Defined densities of multiple genetically marked λ phages were inoculated at known hotspots for contamination on high-fidelity mannequins. HCWs then entered a pre-sanitized simulated hospital room and performed a series of patient care tasks on the mannequins. Sampling occurred on the scrubs and hands of the HCWs, as well as previously defined high-touch surfaces in hospital rooms. Following sampling, the rooms were decontaminated using procedures demonstrated to be effective. Following the conclusion of the simulation, the samples were tested for the presence, identity, and densities of these λ phages.
Findings:
The data generated enabled the determination of the sources and magnitude of contamination caused by the breakdown of established infection prevention practices by HCWs. This technique enabled the standardized tracking of multiple contaminants during a single episode of patient care. Unlike other biological surrogates, λ phages are susceptible to common hospital disinfectants, and allow for a more accurate evaluation of pathogen transmission.
Conclusion:
Whereas our application of these methods focused on healthcare-associated infections and the role of HCW behaviours in their spread, these methods could be employed for identifying the sources and sites of microbial contamination in other settings.
Insights
Healthcare-associated infections (HAIs) are a major concern. This study introduces bacteriophage Lambda (λ) as a novel method to track pathogen transmission from surfaces and healthcare workers (HCWs), improving infection control.
Area of Science:
- Microbiology
- Infection Prevention and Control
- Epidemiology
Background:
- Healthcare-associated infections (HAIs) pose a significant risk to hospitalized patients.
- Identifying pathogen sources and transmission routes is crucial for effective infection control.
- Current methods for monitoring pathogen spread require enhancement.
Purpose of the Study:
- To introduce a novel method utilizing bacteriophage Lambda (λ) for tracking pathogen transmission in healthcare settings.
- To evaluate the efficacy of infection control procedures in simulated hospital environments.
- To identify sources and transmission dynamics of microbial contamination.
Main Methods:
- Genetically marked bacteriophage Lambda (λ) were inoculated onto simulated contamination hotspots on mannequins.
- Healthcare workers (HCWs) performed patient care tasks in a simulated room, with samples collected from HCWs and surfaces.
- Disinfection efficacy was assessed, and phage presence, identity, and density were analyzed post-simulation.
Main Results:
- The bacteriophage Lambda (λ) method successfully identified contamination sources and quantified transmission linked to HCW practices.
- This technique allowed for standardized, simultaneous tracking of multiple contaminants during patient care simulations.
- Bacteriophage Lambda (λ) proved susceptible to hospital disinfectants, enabling accurate evaluation of transmission dynamics.
Conclusions:
- The bacteriophage Lambda (λ) method offers a robust approach for evaluating infection prevention strategies and understanding pathogen spread.
- This technique can be adapted to identify microbial contamination sources and transmission in diverse settings beyond healthcare.
- The study highlights the utility of bacteriophages as biological surrogates for monitoring and controlling infectious agents.
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