I suppose you're referring to Malarone or products similar to Malarone. The preventive medicines are used more by people travelling to those countries, because when you are living in a non-endemic country, you cannot take it every day for medical reasons and for financial reasons. You cannot take a medicine for prevention. The prevention is very often the use of bed nets treated with insecticide. It's very important is to use the test, and that's dovetailing to resistance. Too often in the past when people had a fever, they would immediately think they had malaria and would take some pills for malaria. They were taking too many pills, even though they maybe were not sick with malaria.
Now we push very aggressively the use of very small diagnostic tests that give results in a few minutes to make sure that before you take a medicine, you have malaria. Most of the medicines are for treatment—at least for the population living there.