Dengue is spread by the bite of an 'Ades' Mosquito. This mosquito bites the infected person and then bites someone else who is not affected thus transmitting the infection. These mosquitoes are active during the day time and spread the infection during day time. These mosquitoes live among human beings and breed in discarded tyres, flower pots, water stores etc.
Dengue fever is a flu kind of illness spread by mosquito bites. Dengue and dengue hemorrhagic fever are caused by any of the dengue family virus. This is also widely known as 'Break bone fever' due to the severe joint pain caused during the attack. Dengue can be diagnosed by blood test. The infected person as such cannot spread the infection but can be a source to spread it.