I don't know anything about the fever, but when I was on Bora Bora a few years ago, we circumnavigated the island on bikes. There were lovely homes built on stilts. Lovely that is until we noticed ditches leading from the homes to the ocean. They were open sewers. I don't know if that had anything to do with my intestinal ailment that lasted for about six months. As I say, the colonial rule of the French leaves a lot to be desired.