Malaria survives on healthy red blood cells and carriers don't have many healthy red blood cells. In the same way that people with hemochromatosis deprived bubonic plague of iron, sickle cell carriers deprive malaria of red blood cells. The proactive effect of malaria only works on those who have a copy of sickle cell anemia and not on the disease itself. If you have sickle cell anemia, you are more likely to get malaria. Nevertheless, malaria is such a vicious disease that anything that can help combat it and ensure its survival and reproduction is helpful. Sharon Moalem and Jonathan Prince's book, Survival of the Sickest, highlights the fact that diseases do not always need to be cured, but that we evolve through beneficial mutations. Although the book is primarily about how diseases evolve in humans, Moalem and Prince discuss how we humans shape diseases. By simply obtaining and donating nets, we force the malaria virus to find a new, perhaps less malicious, path to survival and reproduction, a path that may not cure the malaria virus. malaria but which will not make it fatal, similar to the common route.