We cannot keep chasing outbreaks: it’s time to detect them where they begin

OPINION | EZANA KASSA | By the time a dangerous zoonotic disease reaches a hospital ward, the opportunity to prevent it has already been lost.

Health systems around the world have become increasingly effective at detecting infections in people, tracing contacts and responding to outbreaks. But these systems are largely activated only after a pathogen has crossed from animals to humans and began to spread. They are designed to respond—not to prevent.

That reactive approach leaves a critical gap in global health security.

Scientific evidence increasingly shows that many disease outbreaks are fueled not only by human-to-human transmission, but by repeated spillover events from wildlife and livestock into people. Even when one chain of transmission is interrupted, the threat remains if pathogens continue circulating undetected in animals and the environment.

As the Director-General of the World Health Organization observed during a recent Ebola outbreak, the disease “had a big head start, we are still trying to catch up.”

We cannot afford to keep catching up.

More than 60 percent of emerging infectious diseases are zoonotic, and around three- quarters of new infectious diseases originate in animals. Population growth, agricultural expansion, environmental degradation and climate change are increasing interactions between wildlife, livestock and people, creating more opportunities for pathogens to emerge.

These are not remote frontiers. They are productive landscapes where people farm, raise livestock and depend on natural resources for their livelihoods.

This is precisely where surveillance must begin.

The economic case is equally compelling. The cost of preventing pandemics through stronger surveillance, veterinary services and ecosystem management is estimated at only a fraction of the economic losses caused by major outbreaks. COVID-19 alone cost the global economy trillions of dollars and claimed millions of lives, while global analyses estimate that investing roughly US$10–11 billion annually in prevention could substantially reduce the risk of future pandemics—saving countless lives and avoiding losses measured in trillions.

Uganda is demonstrating what this shift can look like.

In Queen Elizabeth National Park, a wildlife veterinary diagnostic laboratory established with support from the United States Government has strengthened the country’s capacity to detect zoonotic pathogens before they spill over into human populations.

The laboratory supports surveillance at the wildlife–livestock–human interface, enabling earlier detection, faster risk assessment and more targeted interventions.

This is prevention in practice.

Through the One Health approach, the Food and Agriculture Organization of the United Nations (FAO) works with governments and partners to strengthen veterinary services, improve animal disease surveillance, monitor risks in agrifood systems and promote coordinated action across the human, animal and environmental sectors. Together with the World Health Organization, the World Organisation for Animal Health and the United Nations Environment Programme, FAO is helping countries build systems that identify risks where they emerge—not only where they are detected in people.

Managing zoonotic disease risk also requires working with communities.

Practices such as hunting and consuming wild meat remain important sources of food and income in many areas. Sustainable solutions cannot ignore these realities. Instead, they must reduce risk through practical measures such as safer handling and processing, stronger veterinary oversight, improved market hygiene and community awareness. Effective prevention depends on trust, participation and locally appropriate solutions.

The evidence is clear. Spillover is not an isolated event; it is an ongoing process. Yet investments remain heavily concentrated on responding after outbreaks occur rather than preventing them at their source.

If we are serious about strengthening global health security, we must invest upstream.

Detecting pathogens before they spread, protecting ecosystems, strengthening veterinary services and integrating surveillance across sectors are not optional additions to outbreak response; they are its foundation.

The next pandemic is unlikely to begin in a hospital. It will emerge quietly, where wildlife, livestock and people interact every day.

The choice before us is clear: continue paying the enormous human and economic costs of reacting to outbreaks or invest now in preventing them. Prevention is not only the smarter investment. It is the only sustainable path to a healthier, safer future.

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Ezana Kassa is the FAO Representative for Uganda and this opinion piece written for the World Zoonotic day 6 th July 2026