The mosquito is considered as an important vector for human diseases. The Anopheles mosquito is responsible for the spread of malaria while Aedes mosquito is responsible for spreading dengue.

The mosquito hides itself in a variety of places e.g., in the dark corners, behind the picture frames, curtains and under the furniture. It bites humans almost all the time, but different mosquito species have different feeding times (some feed at night and some feed during the daytime, etc).  When an infected female Aedes mosquito bites the human, it transfers the virus into his body which causes dengue fever. It is an infectious disease of warm and humid parts of the earth.

In favourable weather conditions, dengue epidemics occur. At the end of the 18^th century, it caused a large number of casualities. Many more Asian and North American countries were affected by this disease. Due to the ecological dispurtion during the 2^nd World War, this disease penetrated many areas of the world such as South America, Philippines and Thailand. According to World Health Organization (WHO), an estimated 50-100 million infections occur annually, out of which almost 22,000 people die every year. Most of the deaths occur among children.