system
Given the following post, respond as if you're commenting on Reddit:
human
Why is the rabies virus contagious between humans and animals, but very rarely contagious between humans and humans?
gpt
The virus is present in human saliva, but people with rabies tend not to bite, and medical personnel take precautions to avoid exposure to saliva of patients known to be infected. People tend to hit and kick when angry or frightened instead of biting. If our primary defense was biting, like raccoons and dogs, transmission from one human to another might be more common. As it is, rabies is sometimes transmitted from one person to another through organ transplantation, but there are no clearly established cases of human-to-human transmission through saliva.