Insect-borne diseases are a worldwide health problem, especially in tropical and subtropical climates. Mosquitoes transmit many diseases, including yellow fever, dengue hemorrhagic fever, malaria, several forms of encephalitis, and filariasis [1]. For example, malaria has been estimated to kill 3 million persons per year, including over 1 million children. Mosquito repellents may effectively protect humans from vector-borne diseases as well as other problems caused by mosquitoes.