World Health Day is celebrated each year on 7^th April to mark the anniversary of the founding of the World Health Organisation (WHO) in 1948.

WHO is the directing and co-ordinating authority for health within the United Nations system. It has the responsibility for providing leadership on global health matters, shaping the health research agenda, setting norms and standards, articulating evidence-based policy options, providing technical support to countries and monitoring and assessing health trends.

In the 21^st century health is seen as a shared responsibility that involves equitable access to essential care and collective defence against transnational threats.

As the boundaries of public health action have become blurred, WHO finds itself having to operate in an increasingly complex and rapidly changing landscape. It now finds itself having to move into other sectors that influence health opportunities and outcomes.

In order to respond to this challenge, WHO now uses a six-point agenda to address these challenges.

1. Promoting Development

Poverty contributes to poor health and poor health anchors huge populations in poverty. Health development is directed by the ethical principle of equality and access to life-saving or health-promoting interventions should not be denied for unfair reasons. Health development is targeted towards poor, disadvantaged or vulnerable groups and the prevention and treatment of chronic diseases, plus addressing the neglected tropical diseases are the cornerstone of WHO's health and development agenda.

2. Fostering health security

One of the greatest threats to international health security is the outbreak of emerging and epidemic-prone diseases. These are occurring in increasing numbers, fuelled by rapid urbanisation, environmental mismanagement, the way that food is produced and traded, and the way that antibiotics are used and misused. Collective security against such outbreaks has been strengthened since the revised International Health Regulations came into force in June 2007.

3. Strengthening health systems

If health improvement is to operate as a poverty-reduction strategy, it is important for them to reach poor and under-served populations. In many parts of the world this is not possible, so making and strengthening health systems is a high priority for WHO. This strengthening will include provision of appropriately trained staff, sufficient financing, access to appropriate technology and the provision of essential drugs.

4. Harnessing research, information and evidence

Evidence provides the means for setting priorities, defining strategies and measuring results. WHO consults with leading experts to generate authoritative health information that enables norms and standards to be set. Evidence-based policy options are articulated and the evolving global health situation can be monitored.

5. Enhancing partnerships

WHO works closely with many partners and uses the strategic power of evidence to encourage partners to implement programmes within their countries that meet their priorities and are aligned to best technical guidelines and practices.

6. Improving performance

WHO participates in ongoing reforms that are aimed at improving its efficiency and effectiveness. It aims to ensure that its staff work in an environment that is motivating and rewarding. Its budget and activities are planned through a process of results-based management with clear expected results to measure performance.

Every year on Word Health Day WHO and its partners choose a different health theme. For 2013 the theme is "Control your Blood Pressure". High blood pressure affects one in three adults worldwide, with many being completely unaware of the fact. It leads to more than nine million deaths each year, including half of all deaths due to heart disease and stroke.

Reducing salt intake is key to reducing high blood pressure and stroke and to reduce the growing burden of non-communicable diseases, so this year WHO recommends reducing salt intake in the general population as a cost-effective strategy.