Has horsepox become extinct?
Authors: Esparza José
Journal: The Veterinary record
Summary
# Editorial Summary: Has Horsepox Become Extinct? The origins of vaccinia virus—the vaccine strain that successfully eradicated human smallpox—remain poorly understood, with horsepox virus suspected as a potential ancestral or contributing source, yet the scientific record offers frustratingly limited documentation to resolve this question. Esparza's 2013 review examines available case reports and historical records of horsepox occurrence in equine populations to assess whether the virus persists in nature or has genuinely disappeared. With genuine horsepox cases rarely documented in recent decades, the author argues that this apparent extinction may permanently obscure the viral genealogy underpinning one of medicine's greatest achievements. Beyond historical curiosity, identifying new cases would provide invaluable molecular evidence for understanding vaccinia's origins and could have implications for understanding poxvirus evolution and cross-species transmission mechanisms. The editorial call emphasises that equine veterinarians and researchers should remain alert to potential horsepox cases and report suspected infections, as even a single confirmed case could substantially advance our knowledge of this significant viral history.
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Practical Takeaways
- •Equine practitioners should be aware of horsepox as a potential emerging or re-emerging disease and report suspected cases to relevant authorities
- •Historical understanding of horsepox's role in vaccine development highlights the importance of documenting and preserving knowledge of equine viral diseases
- •Continued surveillance for horsepox is warranted despite apparent extinction, as clarification of its relationship to smallpox vaccination would inform future vaccine research
Key Findings
- •Few documented cases of horsepox have been recorded in recent years, suggesting the disease may be extinct or extremely rare
- •The historical contribution of horsepox virus to the vaccinia virus strain used in smallpox eradication remains unresolved
- •Identification of new horsepox cases would have significant historical and scientific importance for understanding vaccine development