A bacteria replicates at a much smaller rate than a virus. A virus requires a cell to replicate, bacteria require a much more limited range of hospitable envir

A bacteria replicates at a much smaller rate than a virus. A virus requires a cell to replicate, bacteria require a much more limited range of hospitable environments. Both bacteria and viruses "attempt" to create exact copies, just as a prion does. Admittedly prion replication probably has more accuracy, but that prions occur at all indicates the process allows for natural selection. These don't seem to put prions outside of the "replication" category - they replicate by encountering other proteins, so they are in a body. Their rate of replication is limited (or boosted) by the rate of encountering these proteins. They attempt to create copies of themselves with the chance of failure or different end result.