system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How is rabies "controlled" in the wild? Why doesn't it just destroy large populations of wild mammals?
gpt
Diseases are self-limiting. If they infected and killed everyone in a population, there would be nothing left to infect, and the disease itself would die out. Diseases "want" to be spread (as much as a non-thinking entity can want), and so they take measures to be highly infectious but as low lethality as possible. It's a balancing act. Too strong = run out of victims, to weak = victims become immune and stop spreading it.