Recently I traveled to Nepal and Thailand and choose to use Demal for Malaria and Dengue Fever prevention. I was in both countries for 3 months and returned very healthy. Demal was easy to use and convenient. However, I do not believe I was in contact with either diseases so I cannot say that the product actually worked against the illness. Though in my experience with other travelers I believe a homeopathic alternative and preventative measures are the best way to go for many people.