It's true that diseases are often caused by those things, but in this particular case malaria is caused by the /Plasmodium/ organism and transmitted via infected mosquitoes.
If you're imagining a situation in which one individual in an outlying community gets sick with mysterious symptoms that turn out to be malaria, you have simply failed to grasp the magnitude of the problem.
I have family ties in Southern Africa, I've been there multiple times, I've seen it and I still don't think I grasp the magnitude of the problem. However, on thing I know for sure: The problem is not limited to large portions of the population being infected with malaria. They also have a wide variety of other, quite nasty diseases that will all still be around once you eliminate Malaria - if you succeed at that. The sub-Saharan countries for example suffer from a massive AIDS/HIV epidemic, at some point the estimate was that every third adult in Botswana is infected. Things are better now with about 24% infection rate - that's still a quarter of the population. A common belief was that having sex with a virgin would cure your infection - with predictable results: Think anywhere on the range of merely spreading the epidemic to flat out rape of young virgins. I'm very sorry to respond in kind: I think you fail to grasp the magnitude of the problem.
If you're imagining a situation in which one individual in an outlying community gets sick with mysterious symptoms that turn out to be malaria, you have simply failed to grasp the magnitude of the problem.