Let's think at the scale of species evolution and survival, instead of being mired in memetic myopism, where our conversation uses toxic religious memes to counter them.
I don't understand why memetically sophisticated atheists are still entranced with the positive aspects of evolution, instead of paying attention to its lethal shortcomings.
Darwinian selection hinders our ability to deal with extinction threats such as climate destabilization and relaxed selection, the gradual accumulation of deleterious genes because we've limited human predation and disease. While this issue is not immediately recognizable as a theism/atheism issue, it represents a wider critical perspective that subsumes that conflict.
Sooner or later any system driven by Universal Darwinism will run into limiting factors, because evolution is unaware, reactive, and automatic. No awareness of future possibilities exists in Darwinian selection. Our bodies, our neural anatomy, our memosphere, all were sculpted by mechanical Darwinian selection. Mind viruses are no more planners than measles, despite memeplexes containing such "planning" claims. In sum, two "forces" are behind our inability to cope with climate destabilization: natural selection and memetic selection. Every fiber of our being strains to cope with extinction threats such as climate destabilization as if it were the same kind of challenge the genes and memes that program us have always faced.
The bottom line is that we must take charge of our "selves" in a new way, recognizing how natural selection and memetic selection prevent us from planning for our collective future. This is the case we need to make to the infected.
Fear is not a negative thing unless it is keeping us from living a full life, it indeed keeps us from many a foolish behaviours. We need I think, both sides of our humanity, aggression and compassion, doctor Jekel and Mr Hyde. What was it Nietzsche said, "Becareful in casting out your devil, that you are not casting out your best part." It is a balance that humanity will perhaps better manage in the future.