The best replacement for viruses is bacteria.

The best alternatives to viruses are rated as following:
★★★★★  bacteria
★★★  worms
★★  cells
★★  virii
★★  living organisms
★  living cells
★  viroids
★  rna viruses
★  malware
★  animal cells
★  prions
★  dna viruses
★  living things
★  bacteria size
  eukaryotic cells
  virus'
  bacteria bigger
  pc viruses
  infections
  spyware
  bacteria venn diagram
  bacteria essay
  animal viruses
  plant viruses
  prokaryotes
  bacterial infection
  trojans
  biological viruses
  viri
  computer viruses
  viroids and prions

Your alternative for viruses is not listed? Suggest!
Speaking about viruses, one probably shouldn't forget about vaccines.

Other search terms related to viruses and their ratings are:
★★★★★ vaccines
★★ rashes
frostwire
limewire
vaccinations
You have in mind a companion for viruses and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of viruses in all years. Click on graph for more.
viruses
bacteria
worms