On World Health Day 2026, the World Health Organization (WHO) unites and mobilizes the world under the theme “Together for health. Stand with science.” The event celebrates scientific collaboration to protect the health of people, animals, plants, and the planet.
The campaign marks the anniversary of WHO’s founding on April 7, 1948, launching a year-long public health campaign.
Human health has changed greatly during the past century, thanks to science and international collaboration. The global maternal mortality rate has fallen by more than 40% since 2000, and deaths among children under five have been reduced by over 50%.
Advances in technology, scientific knowledge, skills, and cross-sector collaboration continue to transform once-life-threatening health challenges—like high blood pressure, cancer, and HIV—into manageable issues. This progress is saving and extending lives worldwide. Public health, meanwhile, is not always dramatic. WHO states that factors as simple as clean water, sanitation, and hand hygiene can protect health.
“Science is one of humanity’s most powerful tools for protecting and improving health,” said Tedros Adhanom Ghebreyesus, WHO director-general. “People in every country live longer and healthier lives on average today than their ancestors did, thanks to the power of science. Vaccines, penicillin, germ theory, MRI machines, and the mapping of the human genome are just some of the achievements that science has delivered that have saved lives and transformed health for billions of people.”
Scientific innovations are most powerful when they are widely adopted and used. For example, during the past 50 years, global immunization efforts have saved over 154 million children from infectious diseases. Vaccines have contributed to a 40% reduction in infant mortality. The measles vaccine alone has saved over 90 million children.
In line with the World Health Day 2026 theme, WHO and the G7 Presidency of France convened a One Health Summit in Lyon, France, from April 5 to 7. The event brought together heads of state, scientists, and community leaders to strengthen coordinated action.
WHO will host the Global Forum of its Collaborating Centres network from April 7 to 9, with representatives from over 800 academic and research institutions from more than 80 countries. These Centres support WHO’s research, technical assistance, and capacity-building work worldwide.
“Science transforms uncertainty into understanding and reveals the pathways to protect and heal our communities,” said Dr. Sylvie Briand, WHO chief scientist. “Without the clarity of rigorous scientific inquiry, we risk being led by bias and misconception—and too often toward treatments that fail us or even place us in harm’s way. Today, we must stand together with science so that our collaboration is sustained, supported, and enhanced for the better health of generations to come.”