Internal audits as a tool to assess the compliance with biosecurity rules in a veterinary faculty

Introduction

The present paper proposes a tool to follow up the compliance of staff and students with biosecurity rules, as enforced in a veterinary faculty, i.e., animal clinics, teaching laboratories, dissection rooms, and educational pig herd and farm.

Methods

Starting from a generic list of items gathered into several categories (personal dress and equipment, animal-related items, infrastructures, waste management, management of material/equipment and behavior), a checklist was created for each sector/activity mentioned above, based on the rules and procedures compiled in the Faculty biosecurity standard operating procedures. Checklists were created as Excel™ files. For each sector, several sheets were elaborated, i.e., one per specific activity: for example, the following sheets were created for the equine clinic: class 1-2 hospitalization (class 1 = non-infectious conditions; class 2 = infectious disease with a low or non-existent risk of transmission), class 3 hospitalization (class 3 = infectious disease with a moderate risk of transmission; these patients are suspected of having an infectious disease and being contagious for other patients and/or for humans) and consultation.

Results

Class 4 area, which corresponds to the isolation unit and aims at housing patients suffering from infectious diseases with a significant risk of transmission (including notifiable conditions), was not audited at that period, as it was undergoing renovation works. The audit relied on observations performed by a unique observer to ensure standardization. Observed items were presented as yes/no and multiple-choice questions. A scale from 0 to 3 or 4 (depending on the item) allowed scoring each item, i.e., 0 corresponding to 100% compliance with the procedure and the highest score to the worst situation. A median and average global score was also estimated by category and by activity.

Discussion

The methodology described in the present paper allows estimating the compliance with biosecurity standard operating procedures in a specific sector and/or for a given activity. The identification of criteria needing improvement is a key point: it helps prioritizing actions to be implemented and awareness raising among people concerned. Regular internal auditing is an essential part of a biosecurity plan, the frequency being conditioned by the risk linked to a specific activity or area (i.e., more frequent audits in risky situations).

Susceptibility of Escherichia coli O157:H7 to Disinfectants In Vitro and in Simulated Footbaths Amended with Manure

Escherichia coli O157:H7 is a human pathogen associated with gastrointestinal disease and hemolytic uremic syndrome. Direct contact with ruminants and their feces at agritourism or livestock interaction events is a known source of transmission. Footbath use is a pathogen reduction strategy that may decrease the transmission of E. coli O157:H7 at these interactions. The efficacy of chemical disinfectants in footbaths is not well reported. Our objective was to determine the susceptibility of E. coli O157:H7 toward commonly used disinfectants in vitro and within contaminated footbaths. The minimum inhibitory concentration and the minimum bactericidal concentration (MIC and MBC) and the time-to-kill were determined in vitro for seven E. coli O157:H7 strains using five disinfectant compounds (didecyldimethylammonium chloride [DDAC], glutaraldehyde, hydrogen peroxide, phenol, and sodium hypochlorite). Time-kill assays were performed within simulated footbaths at 22°C, 37°C, and 42°C with and without organic contamination using three commercial disinfectants with similar active ingredients (0.26% Clorox^® Bleach, 0.034% Virex^® II 256, and 1% Virkon^™ S). The MBCs of disinfectants toward E. coli O157:H7 were 3.2, 625, 40, 5000, and 320 ppm of DDAC, glutaraldehyde, hydrogen peroxide, phenol, and sodium hypochlorite, respectively. At 2 × MIC, E. coli O157:H7 reached a 3 log₁₀(colony-forming unit [CFU]/mL) reduction on contact with glutaraldehyde, by 20 min with DDAC and sodium hypochlorite, and by 4 h with phenol and hydrogen peroxide. In simulated footbaths, the commercial disinfectants reduced concentrations by 3 log₁₀(CFU/mL) on contact in the absence of organic contamination, but viable E. coli O157:H7 was recovered from organically contaminated Clorox Bleach and Virex II 256 footbaths. No E. coli O157:H7 was recovered from the Virkon S footbaths after 10 min. This study highlights the ability for organic contamination to compromise the efficacy of disinfectants in footbaths and the importance of choosing an appropriate footbath disinfectant to retain the efficacy.

Evaluation of the Efficacy of Disinfectant Footmats for the Reduction of Bacterial Contamination on Footwear in a Large Animal Veterinary Hospital

Background

Infection control is critical to providing high‐quality patient care. Many veterinary teaching hospitals (VTHs) utilize footbaths or footmats at entrances and key control points throughout the facility to decrease trafficking of pathogenic microorganism on contaminated footwear.

Hypothesis/Objectives

To compare efficacy of 4 disinfectants used in footmats for decreasing bacterial contamination of footwear in a large animal hospital.

Animals

A single adult dairy cow was housed in a stall for 4 days to facilitate stall contamination with fecal material.

Methods

Overboots were experimentally contaminated with organic material in a standardized manner. Each boot was randomly assigned to 1 of 5 treatments (no treatment, or exposure to 1 of 4 disinfectants: an accelerated peroxygen [AHP], a peroxygen [VIRKON], a quaternary ammonium [QUAT], and a phenolic disinfectant [PHENOLIC]) by stepping on a soaked footmat and collecting samples from boot soles. Generalized linear modeling was used to analyze differences in bacterial counts.

Results

Reductions in colony‐forming units (CFUs) on treated boots ranged from no detectable reduction to 0.45 log₁₀ and varied by disinfectant. Percentage reductions in total bacterial counts generally were larger (albeit still modest) for AHP and QUAT disinfectants (range 37–45%) and smallest for the PHENOLIC (no detectable reduction).

Conclusions and Clinical Importance

In general, use of disinfectant footmats was associated with significant reductions in viable bacteria on overboots—albeit with variable efficacy. Footmats may be useful adjuncts to cleaning and disinfection programs for decreasing trafficking of microorganisms throughout VTHs but should not be considered as a sole prevention method.

Shoe soles as a potential vector for pathogen transmission: a systematic review

Shoe soles are possible vectors for infectious diseases. Although studies have been performed to assess the prevalence of infectious pathogens on shoe soles and decontamination techniques, no systematic review has ever occurred. The aim of this study was to perform a systematic review of the literature to determine the prevalence of infectious agents on shoe bottoms and possible decontamination strategies. Three electronic bibliographic databases were searched using a predefined search strategy evaluating prevalence of infectious pathogens on shoe bottoms and decontamination strategies. Quality assessment was performed independently by two reviews with disagreements resolved by consensus. Thirteen studies were identified that supported the hypothesis that shoe soles are a vector for infectious pathogens. Methicillin-resistant Staphylococcus aureus, Clostridium difficile and multidrug-resistant Gram-negative species among other pathogens were documented on shoe bottoms in the health care setting, in the community and among food workers. Fifteen studies were identified that investigated decontamination strategies for shoe soles. A number of decontamination strategies have been studied of which none have been shown to be consistently successful at disinfecting shoe soles. In conclusion, a high prevalence of microbiological pathogens was identified from shoe soles studied in the health care, community and animal worker setting. An effective decontamination strategy for shoe soles was not identified. Studies are needed to assess the potential for contaminated shoes to contribute to the transmission of infectious pathogens.

Patient management

Hospital-associated infections, including those caused by zoonotic agents, represent an increasing concern in veterinary practice. Veterinarians and hospital staff are obligated and expected to provide education about and protection from transmission of pathogens among animal patients and between animal patients and human beings (eg, veterinary staff, volunteers, owners) who come into contact with infected animals. Patient management involves assessing risks of pathogen transmission, identification of animals either suspected of or proved to be infected with a transmissible infectious disease agent, and the implementation of measures that minimize the likelihood of transmission of the infectious agent.