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What topics presented during the 2025 AAEP Infectious Disease Track stood out?

By Duane E. Chappell, DVM

Each year, a carefully selected group of infectious disease studies are presented at the annual AAEP convention. The 2025 educational track did not disappoint. If you missed Denver or couldn’t catch the full infectious disease track, here’s a quick rundown. These 10 abstracts are available to AAEP members and convention registrants (in-person and virtual) through the AAEP Proceedings or convention app.

FIVE RESEARCH THEMES WERE PRESENTED:
1. Diagnostic innovations
a. Noah D. Cohen – Developed and validated a novel ELISA (Protein 92) for improved serodiagnosis of strangles compared to SeM-based assays.

b. Nicola Pusterla – Evaluated a point-of-care (POC) PCR assay for rapid detection of Salmonella spp. in pooled environmental swabs from an equine hospital.

c. Cara Wright – Investigated whether light exercise increases detection of select respiratory viruses and bacteria in healthy horses using noninvasive nose wipes.

2. Epidemiology and monitoring
a. Rebecca C. Bishop – Assessed non-contact infrared thermometry at the perineum and cornea versus rectal temperature for fever detection in ambulatory horses.

b. Nicola Pusterla – Analyzed prevalence factors and coinfections associated with EHV-2 and/or EHV-5 in nearly 10,000 horses presenting with acute fever or respiratory signs.

c. Joy E. Tomlinson – Longitudinally monitored equine parvovirus-hepatitis (EqPV-H) infection dynamics in seven horse herds over four years.

3. Therapeutic advances
a. Kallie J. Hobbs – Tested a novel hemoperfusion cytokine adsorption device (VetResQ) in Lymphocytic Plasmacytic Stomatitis (LPS)-treated horses and measured effects on neutrophil function.

b. Alessandro Migliorisi – Performed a multicenter trial of F(ab′)2 antivenom in U.S. horses bitten by rattlesnakes, evaluating safety and clinical efficacy.

4. Supportive care and pharmacodynamics
a. Camilla Quattrini – Characterized the anti-fibrinolytic pharmacodynamics of IV and oral tranexamic acid and IV ε-aminocaproic acid in healthy adult horses via thromboelastography.

5. Other
a. Claire Card – Compared radiographic ossification, serum iodine, and thyroxine levels in term versus congenital hypothyroid neonatal foals.

STAND-OUT CLINICAL TAKE-HOMES
Protein 92 ELISA for Strangles

• Significantly better receiver-operating characteristic (ROC) curve (95% vs. 88% for SeM, which indicates better overall sensitivity/specificity), less cross-reactivity with S. zooepidemicus.
• Ready-for-practice labs to improve early case detection and herd management.
  F(ab′)2 Antivenom Safety and Efficacy
• No anaphylaxis in 18 horses; 1-vial dosing sufficient in 15 of 18 cases.
• Consider antivenom as an alternate therapy vs. whole IgG or empirical therapies (corticosteroids, antibiotics).

Rapid Environmental Salmonella Monitoring

• POC PCR matches lab qPCR, yields results <24 hours.
• Implement as part of stall or ICU surveillance to curb nosocomial outbreaks.

Nose Wipes from Healthy Horses

• Identification of common and commensal respiratory pathogens was easily achieved.
• Nice alternative when more invasive techniques like nasal swabs or lavages are unavailable or not accepted by the patient.

Given the wide range of equine populations and practitioner interests, this year’s topics addressed many common challenges faced by equine veterinarians. Touching on less familiar topics like antivenom safety, Salmonella testing with POC units, and alternative means of temperature monitoring display the creative side of equine patient care and continue to expand our arsenal of ways to care for the horse. If one of this year’s presentations meets a need in your practice, contact the author to learn more. Merck Animal Health is proud to sponsor the AAEP Infectious Disease Track.

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