Combining two serological assays optimises sensitivity and specificity for the identification of Streptococcus equi subsp. equi exposure.
Abstract: The detection of anti-Streptococcus equi antibodies in the blood serum of horses can assist with the identification of apparently healthy persistently infected carriers and the prevention of strangles outbreaks. The aim of the current study was to use genome sequencing data to develop an indirect enzyme linked immunosorbent assay (iELISA) that targets two S. equi-specific protein fragments. The sensitivity and specificity of the antigen A and antigen C iELISAs were compared to an SeM-based iELISA marketed by IDvet - diagnostic Vétérinaire (IDvet). Individually, each assay compromised specificity in order to achieve sufficient sensitivity (SeM iELISA had a sensitivity of 89.9%, but a specificity of only 77.0%) or sensitivity to achieve high specificity. However, combining the results of the antigen A and antigen C iELISAs permitted optimisation of both sensitivity (93.3%) and specificity (99.3%), providing a robust assay for the identification of horses exposed to S. equi.
Copyright © 2013 Elsevier Ltd. All rights reserved.
Publication Date: 2013-03-01 PubMed ID: 23465547DOI: 10.1016/j.tvjl.2013.01.033Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
- Antibodies
- Comparative Study
- Diagnosis
- Diagnostic Technique
- Disease
- Disease control
- Disease Diagnosis
- Disease Management
- Disease Outbreaks
- Enzyme-Linked Immunosorbent Assay (ELISA)
- Epidemiology
- Equine Health
- Genetics
- Genomics
- Horses
- Infection
- Infectious Disease
- Serology
- Streptococcus
- Veterinary Care
- Veterinary Medicine
Summary
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The research article presents a study that uses genome sequencing data to create a diagnostic assay for detecting the presence of the bacteria Streptococcus equi in horses. By targeting two specific proteins of S. equi, the researchers were able to optimize both the sensitivity and specificity of the assay, significantly improving its ability to accurately identify infected horses.
Development of a Diagnostic Assay
- This research aimed to improve the detection of anti-Streptococcus equi antibodies in horses. S. equi is responsible for a severe equine respiratory disease called strangles, and identifying healthy carriers is crucial to preventing outbreaks.
- The researchers used genome sequencing data to build an indirect enzyme linked immunosorbent assay (iELISA) that targets two proteins specific to S. equi.
- The new iELISA, based on antigen A and antigen C of S. equi, were compared with an existing iELISA diagnostic test marketed by IDvet.
Insights from Comparisons
- Each of the tested assays presented a trade-off between sensitivity (the ability to correctly identify positive cases) and specificity (the ability to correctly identify negative cases). The SeM iELISA from IDvet, while sensitive (89.9%), had a relatively low specificity of 77.0%, meaning it could erroneously identify healthy horses as infected.
- Individually, the newly developed antigen A and antigen C iELISAs also had to compromise between sensitivity and specificity to achieve the required accuracy.
Benefits of the Combined Approach
- The researchers found that by combining the results from the antigen A and antigen C iELISAs, they could optimize both sensitivity and specificity.
- The combination assay showed a high sensitivity of 93.3% and an impressive specificity of 99.3%, thus providing a much more reliable and accurate diagnostic tool for the identification of horses exposed to S. equi.
- This advancement offers significant implications for the management and prevention of strangles outbreaks in horse populations.
Cite This Article
APA
Robinson C, Steward KF, Potts N, Barker C, Hammond TA, Pierce K, Gunnarsson E, Svansson V, Slater J, Newton JR, Waller AS.
(2013).
Combining two serological assays optimises sensitivity and specificity for the identification of Streptococcus equi subsp. equi exposure.
Vet J, 197(2), 188-191.
https://doi.org/10.1016/j.tvjl.2013.01.033 Publication
Researcher Affiliations
- Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket CB8 7UU, UK.
MeSH Terms
- Animals
- Antibodies, Bacterial / blood
- Antigens, Bacterial
- Enzyme-Linked Immunosorbent Assay / methods
- Enzyme-Linked Immunosorbent Assay / veterinary
- Horse Diseases / blood
- Horse Diseases / diagnosis
- Horses
- Sensitivity and Specificity
- Serologic Tests / veterinary
- Streptococcal Infections / blood
- Streptococcal Infections / diagnosis
- Streptococcal Infections / veterinary
- Streptococcus equi
Citations
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- Dominguez-Medina CC, Rash NL, Robillard S, Robinson C, Efstratiou A, Broughton K, Parkhill J, Holden MTG, Lopez-Alvarez MR, Paillot R, Waller AS. SpeS: A Novel Superantigen and Its Potential as a Vaccine Adjuvant against Strangles. Int J Mol Sci 2020 Jun 23;21(12).
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