Equine veterinary journal2026; doi: 10.1002/evj.70348

Fluorescent tagging for assessment of environmental cleaning in an equine hospital.

Joch, D
·
Lyrakis, M
·
Franz, S
·
Biermann, NM

Abstract: Healthcare-associated infections increase morbidity, mortality, and treatment costs in both human and veterinary medicine, and environmental contamination can contribute to their occurrence. Monitoring of environmental cleaning is an important component of multimodal infection control strategies. Fluorescent tagging is a low-cost, practical approach that correlates with reduced environmental contamination in human and small animal hospitals. Its applicability in equine hospitals, where surface characteristics and contamination risks differ, has not yet been evaluated. Objective: To evaluate fluorescent tagging as a monitoring tool for environmental cleaning in an equine hospital, to assess the impact of active feedback, and to validate an objective ImageJ-based assessment against subjective evaluation. Methods: Before-after study. Methods: A commercial fluorescent dye was applied to surfaces in examination rooms and stalls. Fluorescent tag removal was evaluated visually and objectively using standardised photography and ImageJ-based green intensity analysis. Surfaces were sampled repeatedly across two study phases, separated by structured feedback to cleaning staff. Aerobic colony counts (ACC) were performed during phase II adjacent to fluorescent tags to assess bacterial contamination before and after cleaning. Results: Objective ImageJ-based analysis accurately distinguished between removed, partially removed, and not removed fluorescent tags, and there was strong agreement with subjective visual assessment. In examination rooms, provision of feedback resulted in a significant overall improvement in cleaning efficacy, particularly in orthopaedic treatment rooms (room1: log-odds ratio = 1.71; q-value = 0.033, room2: log-odds ratio = 2.11; q-value = 0.01), whereas no improvement was observed in stables (q-value >0.05). The ACC were not associated with fluorescent tag removal grades (q-value >0.05). Conclusions: Subjective and objective assessments were performed by the same non-blinded examiner, single centre design and limited ACC assessment. Conclusions: Fluorescent tagging is a feasible monitoring method for assessing environmental cleaning efficacy in an equine hospital, and objective quantification correlated closely with subjective visual assessment. Active feedback improved cleaning performance in examination rooms but not in stables.

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Publication Date: 2026-10-22 PubMed ID: 42910996DOI: 10.1002/evj.70348Google Scholar: Lookup

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This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

This study evaluated the use of fluorescent tagging as a method to monitor the effectiveness of environmental cleaning in an equine hospital.
The researchers assessed whether providing feedback to cleaning staff improved cleaning outcomes and compared an objective image analysis method with subjective visual assessments.

Background and Purpose

Healthcare-associated infections (HAIs) increase illness, death, and healthcare costs in both humans and animals.
Environmental contamination plays a key role in spreading infections, making thorough cleaning critical.
Fluorescent tagging is a simple and cost-effective technique used in human and small animal hospitals to monitor cleaning quality.
Equine hospitals have different surface types and contamination risks, so the effectiveness of fluorescent tagging in this context was previously unknown.
The study had three main goals:
- Evaluate fluorescent tagging as a cleaning monitoring tool in an equine hospital
- Assess the effect of providing active feedback to cleaning staff on cleaning performance
- Validate an objective computerized image analysis method (ImageJ-based green intensity analysis) against subjective visual assessments

Methods

Study design: Before-and-after study conducted in an equine hospital.
Fluorescent dye was applied to specific surfaces in examination rooms and horse stalls.
After cleaning, fluorescent tag removal was evaluated:
- Visually by a human examiner (subjective assessment)
- Objectively using standardized photos and ImageJ software analyzing green color intensity of tags
Two study phases were conducted:
- Phase I: Initial measurement without feedback
- Intermediate: Cleaning staff received structured feedback on performance
- Phase II: Measurements repeated after feedback to assess impact
Additionally, during phase II, aerobic colony counts (ACC) were taken near fluorescent tags to measure bacterial contamination before and after cleaning.

Results

The objective ImageJ-based method could reliably distinguish between:
- Completely removed fluorescent tags
- Partially removed tags
- Tags not removed at all
There was strong agreement between the objective image analysis and the subjective visual assessments, confirming the validity of the automated approach.
In examination rooms:
- Providing cleaning staff with active feedback significantly improved cleaning effectiveness.
- The orthopaedic treatment rooms showed particularly notable improvements in fluorescent tag removal after feedback, demonstrated by statistically significant log-odds ratios.
There was no significant improvement observed in cleaning performance in the horse stalls (stables) after feedback.
Aerobic colony counts (ACC) did not correlate significantly with the degree of fluorescent tag removal, indicating that bacterial contamination levels were not directly associated with fluorescent tag removal grades in this study.

Conclusions and Limitations

Fluorescent tagging is a practical and feasible approach to monitoring environmental cleaning effectiveness in an equine hospital setting.
The objective ImageJ-based quantification method closely matched subjective visual evaluations, supporting its use for standardized assessments.
Providing active feedback to cleaning staff improved cleaning quality in examination rooms but did not have a measurable impact on cleaning in stables.
Limitations of the study included:
- Assessments were conducted by the same non-blinded examiner, which may introduce bias.
- The study was performed at a single hospital, limiting generalizability.
- Limited aerobic colony count sampling restricted evaluation of links between cleaning efficacy and bacterial contamination.

Cite This Article

APA

Joch D, Lyrakis M, Franz S, Biermann NM. (2026). Fluorescent tagging for assessment of environmental cleaning in an equine hospital. Equine Vet J. https://doi.org/10.1002/evj.70348

Publication

Equine veterinary journal

ISSN: 2042-3306

NlmUniqueID: 0173320

Country: United States

Language: English

Researcher Affiliations

Joch, Desiree

Clinical Centre for Equine Health and Research, Department of Companion Animals and Horses, University of Veterinary Medicine Vienna, Vienna, Austria.

Lyrakis, Manolis

Platform for Bioinformatics and Biostatistics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria.

Franz, Sonja

Clinical Centre for Ruminants, Camelids and Herd Health Management, Department of Farm Animals and Food System Transformation, University of Veterinary Medicine Vienna, Vienna, Austria.

Biermann, Nora Mareike

Clinical Centre for Equine Health and Research, Department of Companion Animals and Horses, University of Veterinary Medicine Vienna, Vienna, Austria.

Grant Funding

Institutional Infection Control Budget

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