There are many species of mosquitoes, which can be found throughout the world. Females are responsible for the bite we suffer. These bites can cause very serious or fatal diseases. In cooler climates, especially seasonal discomfort from bites, but in the tropics they can become the main vectors of diseases. They can transmit different diseases to people and animals; p. eg, malaria, filariasis, yellow fever, encephalitis and dengue. Only a few species of mosquitoes are vectors of human diseases.