Well Google found my answer in a split second just by me taking a look.
  1. Alzheimers Disease: The Novel Finding of Intracellular Biofilms (2017)
  2. Bacterial Biofilms: Development, Dispers...tantibiotic Era (2013)
  3. Potent Antibacterial Nanoparticles against Biofilm and Intracellular Bacteria (2015)
So intracellular biofilms exist and they are already working on getting bullets to them. Furthermore the first article mentions that the Lyme bacteria seems to be the cause of Alzheimers in some cases. It is probably true.

The annoying thing is that, on average, it takes 18 years for research to get into practice. One must seek a doctor that is doing research!