In Reply to: Nusa Lembongan or Gilis? posted by gnik on Sunday, 3. January 2010 at 14:47 Bali Time:
Yes, the Gili's are in a malaria zone and you should take anti-malarials if staying there. Some of the more upmarket places are fogging for mosquitos, but seeing as they use DDT (as recommended by WHO) it is also not something you want to expose yourself to. June is reasonably low risk, but I know a guy who got malaria staying there in April a couple of years ago.
You can get Dengue on Bali, Lembongan or on Lombok any time of the year.