World Health Day is celebrated on April 7 every year to mark the anniversary of the founding of World Health Organization in 1948. Each year a theme is selected that highlights a priority area of public health. The Day provides an opportunity for individuals in every community to get involved in activities that can lead to better health.

The topic for 2014 is vector-borne diseases.

What are vectors and vector-borne diseases?

Vectors are organisms that transmit pathogens and parasites from one infected person (or animal) to another. Vector-borne diseases are illnesses caused by these pathogens and parasites in human populations. They are most commonly found in tropical areas and places where access to safe drinking water and sanitation systems is problematic.

The most deadly vector-borne disease, malaria, caused an estimated 660,000 deaths in 2010. Most of these were African children. However, the world's fastest growing vector-borne disease is dengue, with a 30-fold increase in disease incidence over the last 50 years. Globalization of trade and travel and environmental challenges such as climate change and urbanization are having an impact on transmission of vector-borne diseases, and causing their appearance in countries where they were previously unknown.

In recent years, renewed commitments from ministries of health, regional and global health initiatives -- with the support of foundations, nongovernmental organizations, the private sector, and the scientific community -- have helped to lower the incidence and death rates from some vector-borne diseases.

World Health Day 2014 will spotlight some of the most commonly known vectors -- such as mosquitoes, sandflies, bugs, ticks, and snails -- responsible for transmitting a wide range of parasites and pathogens that attack humans or animals. Mosquitoe s, for example, not only transmit malaria and dengue, but also lymphatic filariasis, chikungunya, Japanese encephalitis, and yellow fever.

Goal -- better protection from vector-borne diseases

The campaign aims to raise awareness about the threat posed by vectors and vector-borne diseases and to stimulate families and communities to take action to protect themselves. A core element of the campaign will be to provide communities with information. As vector-borne diseases begin to spread beyond their traditional boundaries, action needs to be expanded beyond the countries where these diseases currently thrive.

More broadly, through the campaign, we are aiming for the following -- 

• families living in areas where diseases are transmitted by vectors know how to protect themselves;
• travelers know how to protect themselves from vectors and vector-borne diseases when travelling to countries where these pose a health threat;
• in countries where vector-borne diseases are a public health problem, ministries of health put in place measures to improve the protection of their populations; and
• in countries where vector-borne diseases are an emerging threat, health authorities work with environmental and relevant authorities locally and in neighboring countries to improve integrated surveillance of vectors and to take measures to prevent their proliferation.