The great mosquito swap

Every year, it’s estimated that nearly 400 million people around the world are infected with dengue fever, a potentially fatal illness that’s passed on by mosquitoes. No vaccine is effective at preventing people catching the disease, but what if the mosquitoes themselves were treated to stop them spreading it?In one city that is severely affected – Medellin in Colombia — an ambitious project is underway to swap wild mosquitoes for a variety that is identical in every way, but with one crucial difference. These mosquitoes have been bred from specimens injected with bacteria that make it impossible to transmit not just dengue, but also the Zika and chikungunya viruses, and Yellow Fever.Buoyed by successful projects in Australia, the World Mosquito Program is releasing millions of newly-minted mosquitoes across Medellin, in the hope that they will replace the wild population. And to reassure the public, schoolchildren are being taught to love mosquitoes, and even to breed them — a message that contradicts what they’ve been brought up to believe.Presenter: Tom Colls Reporter / Producer: William Kremer(Photo Caption: The Aedes Aegyptii Mosquito / Photo Credit: Getty Images)