system
Given the following post, respond as if you're commenting on Reddit:
human
Why are antiviral medications so much less prevalent than antibacterial?

It seems like we have a lot of defenses against bacterial infections, and have had them for quite some time.  I'm curious why it appears that anti-viral equivalents are so much less pervasive?  And the ones we have, seem so much more dangerous than the antibacterial counterparts.
gpt
There are fewer unique targets, since viruses mostly use our own cellular machinery. We end up having to target the few enzymes and proteins they have, such as viral proteases or reverse transcriptases. We can also sometimes produce neutralizing antibodies that target viral surface proteins, which opens up some new options, but even there we also have to be careful that the viral epitopes aren’t too similar to human proteins. 

In contrast, bacteria have whole suites of enzymes and proteins that are often unique or significantly different than their human analogs, so we can build compounds targeting them that are less likely to interrupt human cells.