system
Given the following post, respond as if you're commenting on Reddit:
human
Are there viruses who can replicate in the human body without damage?
gpt
Techniicaalllyyy. Going off of the wording of the question, one could argue that bacteriophages inside your gut would qualify. These are a couple different orders of viruses that exclusively infect bacteria, and as such are not going to interfere with any of your human cells, causing damage. 

They're found basically everywhere on earth, (including your gut microbiome) and are thought to number ~10³¹. More than all living organisms combined on earth! They are absolutely fascinating to learn about

HOWEVER the gut microbiome is a unique ecosystem, so there is the argument that the death of too much "good bacteria" from phages killing may result in indirect damage from causes such as pathogenic bacteria over-extending their welcome in the gut. But the vast majority of people are going to have phages happily multiplying inside them to maintain a healthy balance of bacteria to keep that gut in check. 

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