The 9th World One Health Congress is taking place in Lisbon, Portugal, from September 4 to 7, 2026. The meeting brings together researchers, policymakers and international organisations around a simple idea: human health cannot be separated from animal health and the environment.
The World Health Organization is participating alongside the Food and Agriculture Organization, the UN Environment Programme and the World Organisation for Animal Health—the four bodies often described as the One Health Quadripartite.
What does One Health mean?
One Health is a coordinated approach to problems that cross biological and institutional boundaries. A virus moving between wildlife, livestock and people is an obvious example, but the idea is wider than outbreaks.
Antimicrobial resistance can be shaped by antibiotic use in hospitals, farms and food production. Water contamination can affect ecosystems, animals and nearby communities. Land-use change can alter how people and wildlife encounter one another.
No single ministry can solve those problems alone.
Why the Lisbon congress matters
Scientific conferences can produce valuable research without changing practice. The 2026 congress is placing visible emphasis on the science-policy interface, financing and country implementation.
WHO-listed sessions include the economics of One Health, investment design, field epidemiology, workforce skills and implementation of the Joint Plan of Action. That agenda reflects a practical challenge: governments may accept the concept while struggling to fund shared surveillance, laboratories and response systems.
Antimicrobial resistance is a central test
When bacteria and other microbes evolve resistance to medicines, routine infections become harder to treat. Misuse and overuse of antimicrobials can occur across human medicine, veterinary practice and agriculture.
A One Health response combines better prescribing, infection prevention, vaccination, sanitation, farm biosecurity and environmental monitoring. Focusing on only one sector can shift the problem rather than reduce it.
What useful outcomes would look like
The value of the congress should be judged after the closing session. Useful outcomes include interoperable surveillance, clear data-sharing rules, funding for local capacity and measurable national plans.
Low- and middle-income countries also need access to diagnostics and trained staff. A framework that depends on expensive systems unavailable where risks are highest will not deliver global protection.
Why this affects everyday life
Food safety, pet health, clean water and medicine effectiveness are all One Health issues. The approach does not claim every illness comes from animals or the environment. It asks decision-makers to check the connections before designing an isolated response.
That mindset is especially important when climate change shifts species ranges, extreme weather damages sanitation and global trade moves people, food and animals rapidly across borders.
WHO's official congress page lists the event and major sessions. For more international risk coverage, read our El Niño 2026-27 explainer or visit world.
