Slogan and key messages
The slogan for this year’s World Health Day campaign is "Small bite, big threat".
Mosquitoes, flies, ticks, bugs and freshwater snails can spread diseases that cause serious illness and death.
Diseases such as malaria, dengue, leishmaniasis and yellow fever are preventable, yet they have the biggest impact on some of the world’s poorest people.
More than half of the world’s population is at risk of these diseases. Increased travel, trade and migration make even more people vulnerable.
You can protect yourself and your family by taking simple measures that include sleeping under a bednet, wearing a long-sleeved shirt and trousers and using insect repellent.