Dengue Fever

I heard that once exposed to Dengue you develop a resistance to the pathogen, making reinfection unlikely, any truth to this? 

I had a friend who was infected twice- in Chiang Mai.

Also, I haven't seen any posting here mentioning that Dengue mozzies tend to bite in the daytime, malarial types bite mostly at night....

Ajarn, you missed the second line if my initial post.

Dengue is carried and transmitted by the Aedes aegypti mosquito, which commonly bites during the day, from 5 AM onwards with dawn showing the highest incidence of biting.

Regarding reinfection: There are four types of Dengue. If you are infected with type 1, you will gain immunity to type 1 etc., however you will still be susceptible to infection by the types you have not yet contracted.

Furthermore, there is some evidence that if you suffer from additional incidents of Dengue, they can be more dangerous.