Related by context. Frequent words. (Click for all words.) 67 bacterium 64 Bacillus 62 parasite 62 bacteria 59 coli 59 pathogen 59 naturally occurring bacteria 58 bacterial strains 58 mycobacteria 57 parasites 57 H. pylori 56 Pseudomonas aeruginosa 56 microorganism 56 parasitic worms 56 Helicobacter pylori 56 Aspergillus 56 Streptococcus 56 S. aureus 56 micro organism 56 mutant strain 56 pathogens 56 bacterial 55 toxin 55 Giardia 55 pathogenic bacteria 55 Pseudomonas 55 organism 54 Clostridium 54 microbe 53 causative agent 53 Mycobacterium tuberculosis 53 microorganisms 53 phages 53 anaerobic bacteria 53 noroviruses 53 retrovirus 53 micro organisms 53 P. aeruginosa 52 bacteriophages 52 staphylococcus 52 Bacillus anthracis 52 prions 52 Salmonella bacteria 52 Lactobacillus 52 pathogenic 52 phage 52 streptococcus 52 mycoplasma 52 microbes 52 Candida albicans 52 infectious organisms 52 S. pneumoniae 51 organisms 51 lactic acid bacteria 51 Strep 51 germ 51 Plasmodium 51 Staphylococcus aureus 51 fungus 51 multidrug resistant 50 Mycoplasma 50 protozoa 50 EHEC 50 viruses 50 Shigella 50 sialic acid 50 malaria parasites 50 roundworm 50 Pathogens 50 Noroviruses 50 viral particles 50 virulent strain 50 virulent strains 49 fungi 49 virulent 49 Streptococcus pneumoniae 49 infective 49 single celled 49 herpes virus 49 alga 49 roundworms 49 tapeworm 49 viral strains 48 bacterial pathogens 48 germs 48 Bacteria 48 aureus 48 bacteriophage 48 virus infects 48 yeast 48 rhinovirus 48 vaccinia virus 48 Escherichia coli 48 measles virus 48 anthrax bacteria 48 giardia 48 spores 48 Staphylococcus 48 Prions 48 P. falciparum 48 proteases