Bridging hosts: Domestic horse density and Hendra virus spillover risk in a changing landscape.
Authors: Linnegar Belinda, Hoegh Andrew, McCallum Hamish, Peel Alison J
Journal: Equine veterinary journal
Summary
# Bridging hosts: Domestic horse density and Hendra virus spillover risk in a changing landscape Climate and land-use changes are reshaping wildlife behaviour and movement patterns, fundamentally altering where and how pathogens encounter domestic animals—yet spillover research typically concentrates on wildlife reservoirs or human transmission rather than the bridging role of livestock. Linnegar and colleagues examined how domestic horse density influences Hendra virus spillover risk across changing Australian landscapes, investigating the epidemiological mechanisms by which horses facilitate pathogen transmission between flying fox reservoirs and human populations. The research identified critical density thresholds and spatial patterns demonstrating that concentrated horse populations substantially amplify spillover probability, with implications for both the timing and geographic location of outbreaks in human communities. These findings warrant serious consideration in biosecurity planning and land management decisions, particularly as climate shifts drive both wildlife and equine distribution changes across endemic regions. For equine professionals working in areas with known Hendra circulation, understanding how local horse density affects disease risk can inform herd management protocols, vaccination strategies, and coordination with wildlife monitoring initiatives to reduce amplification potential.
Read the full abstract on PubMed
Practical Takeaways
- •Monitor local horse population density and landscape changes as potential risk factors for emerging infectious disease exposure in your practice area
- •Implement enhanced biosecurity protocols during periods of environmental change or increased wildlife-domestic animal contact
- •Educate horse owners about the zoonotic spillover risk and the role of domestic horses as potential bridging hosts for wildlife pathogens
Key Findings
- •Domestic horse density influences Hendra virus spillover risk in changing landscapes
- •Horses function as bridging hosts facilitating emergence of highly pathogenic diseases
- •Anthropogenic climate and landscape changes drive wildlife behavioural shifts increasing pathogen exposure risk
- •Livestock and companion animals play amplifying roles in disease emergence rather than serving solely as terminal hosts