Preventing zoonotic disease emergence requires addressing the animal welfare conditions in which pathogens evolve and spread, making welfare and pandemic prevention inseparable.
Zoonotic disease prevention is increasingly recognized as inseparable from animal welfare. The welfare conditions that allow rapid virus evolution - high-density housing, immunosuppressed animals, inadequate veterinary care - are precisely those that create pandemic risk. COVID-19 demonstrated the catastrophic human cost of zoonotic spillover events that originate in or are amplified by poor animal welfare conditions. Improving farm animal welfare, reducing live wildlife trade, and managing human-wildlife interfaces are simultaneously welfare improvements and pandemic prevention investments. The economic case for welfare improvement, when pandemic risk costs are included, is stronger than welfare costs alone suggest.