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Equine veterinary journal2025; doi: 10.1111/evj.14527

Molecular detection of pathogens in an equine fever diagnostic panel: 2019-2023.

Abstract: A common diagnostic approach for febrile horses is to test for a panel of potential pathogens. Panels are curated by expert opinion and vary between diagnostic laboratories. Objective: To report the results of a newly developed equine fever diagnostic panel (EFDP) between 2019 and 2023 and evaluate the frequency of positive results. Methods: Retrospective descriptive study. Methods: The EFDP requires submission of whole blood, nasal swab, and faecal samples, and includes PCR tests for 12 pathogens that can present as fever without localising signs of illness or infection. Submission metadata and results of all submissions with EFDP performed between July 2019 and April 2023 were tabulated. Submissions were excluded if horses were <1 year old or any tests were cancelled. Results: One or more pathogens were identified on the EFDP in 366/961 (38%) cases. The most common pathogens identified were Anaplasma phagocytophilum and beta coronavirus. Co-infections with 2 or 3 pathogens were identified in 48/366 (13%) positive panels. Ancillary testing detected Salmonella in 5/23 (22%) submissions. Conclusions: Clinical information regarding the cases was lacking. The majority of submissions originated from the northeastern United States, and results might not be generalisable to other geographic regions. Conclusions: The panel was able to detect a possible causative agent in approximately a third of cases. Based on the results of ancillary testing and recent literature, Potomac Horse Fever PCR on faeces (in addition to whole blood) and Salmonella culture have been added to the EFDP as of November 2024.
© 2025 The Author(s). Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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Publication Date: 2025-05-19 PubMed ID: 40384355DOI: 10.1111/evj.14527Google Scholar: Lookup
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Summary

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.

The research analyzes the results and efficiency of a newly developed equine fever diagnostic panel (EFDP) for detecting horse fever-inducing pathogens between 2019 and 2023. The study finds that the EFDP was able to identify potential causative agents in around a third of the cases.

Objectives and Methods

  • The main goal of the study was to assess the results of the equine fever diagnostic panel (EFDP) introduced in 2019, and determine the frequency of positive results.
  • The EFDP necessitated the submission of various samples including whole blood, nasal swab, and faecal samples from horses.
  • PCR tests included in the EFDP were designed to detect 12 pathogens which could cause fever without any localising signs of illness or infection.
  • Metadata and results from submissions with EFDP conducted between July 2019 and April 2023 were systematically collated and tabulated for evaluation.
  • Data from horses younger than a year old, and from tests which were cancelled, were excluded from the study.

Results

  • One or more pathogens were identified through the EFDP in 38% of the cases (366 out of 961).
  • The most commonly identified pathogens were Anaplasma phagocytophilum and beta coronavirus.
  • Co-infections involving 2 or 3 different pathogens were found in 13% of the positive panels (48 out of 366).
  • Additional testing highlighted the presence of Salmonella in 22% of the submissions (5 out of 23).

Conclusions and Limitations

  • A significant limitation of the study was the insufficient clinical information on the cases.
  • Most of the data for the study came from the northeastern United States, thus the results might not be applicable or generalizable to other geographic regions.
  • Despite these limitations, the panel was still able to detect a potential causative agent in about a third of the cases.
  • Based on the results of additional testing and recent literature, additional tests including Potomac Horse Fever PCR on faeces (in addition to whole blood) and Salmonella culture have been included in the EFDP as of November 2024 to improve diagnostic accuracy.

Cite This Article

APA
Pinn-Woodcock TL, Aprea MS, Lejeune M, Tomlinson JE. (2025). Molecular detection of pathogens in an equine fever diagnostic panel: 2019-2023. Equine Vet J. https://doi.org/10.1111/evj.14527

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Pinn-Woodcock, Toby L
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Aprea, Melissa S
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Lejeune, Manigandan
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Tomlinson, Joy E
  • School of Veterinary Medicine, University of Pennsylvania, New Bolton Center, Kennett Square, Pennsylvania, USA.

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