system
Given the following post, respond as if you're commenting on Reddit:
human
Rabies is a disease with (untreated) near-100% fatality and a prolonged transmissible period. How is it contained in the animal kingdom?

Rabies is near-universally fatal unless treated early, at least in humans. In animals such as canines, it also provokes aggression and attacking others, which helps spread the disease, over a prolonged period of time and with an easy infection vector.

Diseases are generally thought to fall on the mortality-transmissibility curve, where highly lethal diseases generally kill the host before many others are infected, while highly infectious diseases are usually less lethal, with both ends of the curve limiting the diseases' destructiveness at the species level. Rabies, however, seems to be strong in both categories. What stops it from completely decimating every species it targets?
gpt
> with an easy infection vector.

It's actually not a very easy infection vector.  Spread by respiratory droplets or through contaminated water is an easy infection vector, requiring one animal to have to actually get physically bitten by another is actually a pretty difficult infection vector, since most animals will go out of their way to not get bitten.  Furthermore, in any aggressive alteraction there's a significant chance that either the rabid animal or the bitten animal will die outright of other causes, which reduces further spread.