They may be tiny, but they are deadlier than dynamites. Mosquitoes are the carriers of some of the most dangerous diseases in the world. In olden times, people used natural extracts from plants to keep these enemies at bay. Today, mosquito repellents, in the form of mats, liquid vaporisers, sprays or lotions have made the daunting task easy. Ever wondered how these repellents are made? Or how they work?