Your correct. Dengue fever is passed on only by a particlular mosquito. Funny enough, it usually occupies indoor areas mostly. I was bitten and caught Dengue in 1996 in Ambergris Caye. It was because I hadn't paid much attention to the mosquitos in the room.
I now go through a regimen with a towel every time I get a new hotel room. I kill every mosquito I can find by swatting them, and then I give the room a spraying of bug killer and leave the room for about an hour.
I don't get bitten in bed any longer.
The bottom line is that the mosquitos indoors are more dangerous than the ones outdoors, so kill them before they get you.
Jim