I believe the general problem with bacterial viruses, is that our body mounts a immune response against them.[1] It works okay for a little bit, but because our

I believe the general problem with bacterial viruses, is that our body mounts a immune response against them.[1] It works okay for a little bit, but because our immune system "learns" (e.g. clonal selection) the second time they are used they aren't usually effective. I've read that they kept being used in Russia because Russia didn't have the industrial capacity for antibiotic production & refinement. It would be interesting to know if the Russian/Polish medical communities learned anything novel about bacterial viruses though. [1] Our immune system doesn't know that they're harmless, and the tricks that some viruses use to avoid are immune system are typically harmful to us, so you wouldn't want to use those ones.