The Effect of Vaccination Status on Total Lymphocyte Count in Horses Affected by Equine Herpes Virus-1 Myeloencephalopathy
Simple Summary
Abstract
1. Introduction
2. Material and Methods
2.1. Inclusion Criteria
2.2. Clinical Parameters on Admission and Hospitalization
2.3. Laboratory Parameters on Admission and Hospitalization
2.4. Vaccination Status of Referred Horses
2.5. Comorbidities Developed During Hospitalization
2.6. Statistical Analyses
3. Results
3.1. Outbreak Details for Inclusion Criteria
3.2. Clinical Parameters During Admission and Hospitalization
3.3. Laboratory Parameters During Admission and Hospitalization
3.4. Vaccination Status of Admitted Horses
3.5. Comorbidities During Hospitalization
3.6. Impact of Vaccination on Clinical Parameters and Disease Severity
3.7. Impact of Vaccination on Laboratory Parameters
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
COVID-19 | Coronavirus 2019 |
CNS | central nervous system |
EHM | equine herpesvirus myeloencephalopathy |
EHV-1 | equine herpesvirus type 1 |
FEI | International Equestrian Federation |
PBMCs | peripheral blood mononuclear cells |
PCR | polymerase chain reaction |
SARS-CoV-2 | severe acute respiratory syndrome coronavirus 2 |
SIRS | systemic inflammatory response syndrome |
VTH | veterinary teaching hospital |
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EHM Outbreak Parameters | Vaccination Status Against EHV-1 Prior to Outbreak | p Value | |
---|---|---|---|
Correctly Vaccinated | Incorrectly Vaccinated | ||
Number of affected horses (n) | 6 | 4 | - |
Age years old | 10 ± 2 | 8.2 ± 1.5 | NS |
Gender (female/gelding ratio) | 3/3 | 1/4 | NS |
Fever (%) | 50.0 | 0.0 | NS |
Lymphopenia at admission (%) | 50.0 | 100.0 | NS |
Lymphocytes at admission (×103 cells/µL) | 1.51 ± 0.30 | 1.08 ± 0.15 | 0.02 |
Systemic complications (%) | 33.3 | 0.0 | NS |
Median ataxia grade (Min.–Max.) | 3 (0–4) | 3 (2–3) | NS |
Mean hospitalization time (days) | 15.5 ± 1.2 | 12.5 ± 1.2 | 0.01 |
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de la Cuesta-Torrado, M.; Vitale, V.; Velloso Alvarez, A.; Neira-Egea, P.; Diss, C.; Cuervo-Arango, J. The Effect of Vaccination Status on Total Lymphocyte Count in Horses Affected by Equine Herpes Virus-1 Myeloencephalopathy. Animals 2025, 15, 1019. https://doi.org/10.3390/ani15071019
de la Cuesta-Torrado M, Vitale V, Velloso Alvarez A, Neira-Egea P, Diss C, Cuervo-Arango J. The Effect of Vaccination Status on Total Lymphocyte Count in Horses Affected by Equine Herpes Virus-1 Myeloencephalopathy. Animals. 2025; 15(7):1019. https://doi.org/10.3390/ani15071019
Chicago/Turabian Stylede la Cuesta-Torrado, María, Valentina Vitale, Ana Velloso Alvarez, Patricia Neira-Egea, Clairianne Diss, and Juan Cuervo-Arango. 2025. "The Effect of Vaccination Status on Total Lymphocyte Count in Horses Affected by Equine Herpes Virus-1 Myeloencephalopathy" Animals 15, no. 7: 1019. https://doi.org/10.3390/ani15071019
APA Stylede la Cuesta-Torrado, M., Vitale, V., Velloso Alvarez, A., Neira-Egea, P., Diss, C., & Cuervo-Arango, J. (2025). The Effect of Vaccination Status on Total Lymphocyte Count in Horses Affected by Equine Herpes Virus-1 Myeloencephalopathy. Animals, 15(7), 1019. https://doi.org/10.3390/ani15071019