Welfare of Animals in Zoonotic Disease Contexts: Spillover, Surveillance, and Sentience

The intersection of zoonotic disease and animal welfare is growing in importance. Understanding how disease surveillance and response affects animal welfare is essential for One Health approaches.

Key Facts

Zoonotic diseases — those that transmit between animals and humans — account for 60% of all emerging infectious diseases, making human-animal disease interface a major public health concern
COVID-19, SARS, Ebola, MERS, avian influenza, and Nipah virus all originated in animal reservoir species — wildlife trade and habitat encroachment are primary drivers of spillover
Culling of wild and farmed animal populations for disease control is a major welfare event — millions of animals are killed in outbreaks of avian influenza, foot-and-mouth, and ASF annually
Surveillance methods including trapping, sampling, and collaring of wildlife for disease monitoring cause distress and injury if not conducted with welfare best practices
One Health frameworks — recognising the interdependence of human, animal, and environmental health — increasingly require welfare integration in disease surveillance and response planning
Trophy hunting bans and wildlife trade restrictions motivated by disease risk have welfare implications for the animals involved in these trades
Biosafety culling of farm animal populations for disease control is typically conducted under time pressure that compromises welfare — as documented in COVID-19 mink culls

Welfare Considerations

The welfare dimensions of zoonotic disease responses are often overlooked in the public health focus on human protection. Mass culling of farmed animals — the standard response to HPAI, FMD, and ASF outbreaks — involves killing millions of animals, often under emergency conditions that compromise the humane standards that would apply in normal slaughter. Wildlife disease surveillance requires trapping, handling, and sometimes killing of wild animals whose welfare during these procedures deserves consideration. The One Health framework — which recognises that human, animal, and environmental health are interconnected — provides an intellectual basis for integrating animal welfare into disease surveillance and response, but this integration remains incomplete in practice in most countries.

What You Can Do

Advocate for One Health frameworks to explicitly include animal welfare standards in disease surveillance and outbreak response protocols
Support investment in rapid-deployment, humane culling infrastructure that can be mobilised quickly in disease outbreaks without compromising welfare
Push for wildlife disease surveillance protocols to include welfare best practices for trapping, handling, and sampling of wild animals
Donate to wildlife disease research organisations that study spillover risk and prevention — preventing outbreaks is better for both animal and human welfare than responding to them
Engage with food system reform that reduces live animal trade, high-density farming, and human encroachment on wildlife habitat — these are the primary drivers of zoonotic spillover
Support legislation restricting wildlife trade that poses high disease spillover risk — both the human disease and wildlife welfare arguments support these restrictions
Raise awareness of the One Health connection — public understanding of the links between wildlife trade, farm animal conditions, and human pandemic risk motivates integrated policy responses