Environmental persistence of equid herpesvirus type-1

Area of Science:

• Veterinary Virology
• Equine Infectious Diseases
• Environmental Microbiology

Background:

• Equid herpesvirus type 1 (EHV-1) is a prevalent pathogen in horse populations, responsible for significant respiratory, reproductive, and neurological issues.
• Controlling EHV-1 in housing environments is difficult due to porous materials like wood and bedding.
• Understanding EHV-1's environmental persistence is crucial for effective disease management.

Purpose of the Study:

• To assess the environmental persistence of EHV-1 on common equine facility materials under various conditions.
• To determine how different environmental factors (temperature, location) influence EHV-1 survival on surfaces.
• To evaluate the potential for EHV-1 transmission from contaminated environments.

Main Methods:

• An experimental study exposed EHV-1 to leather, fabric, wood shavings, straw, and polystyrene under controlled conditions (4°C, indoor, outdoor).
• Virus viability was quantified using plaque-forming unit (PFU) assays and quantitative PCR (qPCR) at multiple time points up to 48 hours.
• Standard inoculum was used, not mimicking natural nasal secretions, which may affect virus sensitivity.

Main Results:

• Viable EHV-1 was detected on all tested materials up to 48 hours, though persistence decreased over time.
• The outdoor environment demonstrated the most significant reduction in EHV-1 persistence, followed by indoor and 4°C conditions.
• Wood shavings showed the greatest impact on EHV-1 persistence, followed by leather, straw, fabric, and polystyrene.

Conclusions:

• Environmental conditions significantly influence EHV-1 persistence, with reductions observed within the first 3 hours.
• Despite rapid initial decline, viable EHV-1 can persist for 48 hours, indicating a potential transmission risk.
• Implementing barrier precautions is recommended to prevent the spread of EHV-1 from environmental reservoirs.