'Sweaty billboard' could help fight Zika

A billboard that attracts and kills mosquitoes has been designed by marketing agencies in Brazil.

The board releases a mixture of a lactic acid solution that mimics the smell of human sweat, and carbon dioxide, which is in human breath.

Its inventors have released the blueprint for free and are encouraging people around the world to make them.

However, one expert warned it could attract insects to areas where there are many humans.