But WHO doesn’t just make recommendations – it helps countries use them to keep more people healthy. For decades, WHO staff have worked alongside governments and health professionals on the ground. In the early years, there was a strong focus on fighting infectious killers like smallpox, polio and diphtheria. The Expanded Programme on Immunization, for example, set up by WHO in the early 1970s, has, with the help of UNICEF, Gavi, the Vaccine Alliance, and others, brought lifesaving vaccines to millions of children.

In the last century, access to antibiotics, clean water and improved sanitation became powerful weapons in preventing infectious disease. A real challenge now is to protect the effectiveness of antibiotics, through a global programme to fight antimicrobial resistance, and to ensure that the entire world benefits from safe water and sanitation to prevent infections occurring in the first place. Today, access to clean drinking water and safe sanitation facilities is one of the most obvious examples of the stark divisions between rich and poor.

In recent decades, the world has seen a rise in noncommunicable diseases such as cancer, diabetes and heart disease. Driven by forces such as rapid unplanned urbanization, globalization of unhealthy lifestyles and population ageing, these diseases now account for 70%of all deaths. So WHO has shifted focus, along with health authorities around the world, to promote healthy eating, physical exercise and regular health checks.

The Organization has run global health campaigns on the prevention of diabetes and high blood pressure and on healthy cities. It negotiated the WHO Framework Convention on Tobacco Control, a formidable tool to help reduce disease and death caused by tobacco.

But these are not the only forms of noncommunicable illness. Mental health is a major issue around the world. WHO has helped extend mental health care in more than 110 countries. This is thanks in part to training nonspecialists and increasing mental health and psychosocial support for people affected by natural disasters and conflict.

At the same time, work has ramped up in areas such as violence and injury prevention, highlighting the devastating consequences of maltreatment of children, sexual violence and elder abuse, as well as road traffic accidents and drowning. And WHO has called attention to the importance of catering to the needs of people with disabilities, through strengthened rehabilitation services in health programmes and better access to assistive technologies.

Tracking progress in all of these areas requires a strong monitoring system. Data collected from countries across the world is stored in and shared through WHO’s Global Health Observatory. This powerful tool helps countries get a clear picture of who is falling sick, from which disease, and where, so that efforts can be targeted where they are needed most.

The ability to collect and analyze data has been critical to WHO’s work to improve health through the life-course – from before birth right through to the last years of life. This approach, with its focus on critical periods such as pregnancy, early childhood, and adolescence, emphasizes the importance of getting a healthy start in life, and of making the extra effort to reach people who might otherwise get left behind – all too often, women and girls living in the poorest environments.