| Bacterium | Site of infection/clinical syndrome |
| Bacillus anthracis | anthrax |
| Bacillus cereus | food poisoning/food-borne enteritis |
| Bacteroides sp. | abdominal sepsis, abscesses (including cerebral) |
| Bordetella pertussis | whooping cough |
| Campylobacter sp. | food-borne enteritis |
| Chlamydia pneumoniae | respiratory tract (atypical pneumonia) |
| Chlamydia trachomatis | genital tract, eye |
| Clostridium botulinum | botulism |
| Clostridium difficile | antibiotic-associated diarrhea (inc pseudomembranous colitis) |
| Clostridium perfringens | gas gangrene, abdominal sepsis, food poisoning |
| Clostridium tetani | tetanus |
| Corynebacterium diphtheriae | diphtheria |
| other Corynebacterium sp. | urinary tract, “line” colonisation/infection |
| Enterococcus spp. (formerly Streptococcus) | urinary tract, “line” colonisation/infection, abdominal sepsis |
| Escherichia coli | urinary tract, abdominal sepsis, neonatal septicaemia/meningitis |
| Haemophilus influenzae | non-capsulate: respiratory tract (inc exacerbation COAD, middle ear) |
| Helicobacter pylori | atrophic gastritis, peptic ulcer disease |
| Klebsiella sp. | urinary tract, abdominal sepsis |
| Legionella pneumophila | Legionnaires disease (Pontiac fever, “atypical” pneumonia) |
| Listeria monocytogenes | septicaemia/meningitis (esp neonates & immunosuppressed) |
| Moraxella catarrhalis | respiratory tract (inc exacerbation COAD, middle ear) |
| Mycobacterium leprae | leprosy |
| Mycobacterium tuberculosis | tuberculosis |
| other Mycobacterium sp. | rarely tuberculosis, possibly other infections in immunosuppressed |
| Mycoplasma pneumoniae | respiratory tract (“atypical” pneumonia) |
| Neisseria gonorrhoeae | gonnorhoea |
| Neisseria meningitidis | septicaemia/meningitis |
| Proteus sp. | urinary tract, abdominal sepsis |
| Pseudomonas aeruginosa | urinary tract, abdominal sepsis, respiratory tract in cystic fibrosis patients |
| other Pseudomonas sp. | “line” colonisation/infection |
| Salmonella typhi/paratyphi | typhoid fever |
| other Salmonella sp. | food-borne enteritis |
| Shigella sp. | food-borne enteritis |
| Staphylococcus aureus | skin & soft tissue (eg abscess/cellulitis/fascitis), food poisoning & other toxin-mediated disease, endocarditis, osteomyelitis |
| Staphylococcus epidermidis | “line” colonisation/infection (& other prostheses) |
| Streptococcus agalactiae | neonatal septicaemia/meningitis |
| Streptococcus pneumoniae | respiratory tract (including lobar pneumonia, exacerbation COAD, middle ear), meningitis |
| Streptococcus pyogenes | skin & soft tissue (e.g. abscess/cellulitis/fascitis), pharyngitis (rheumatic fever, glomerulonephritis) |
| Streptococcus viridans | bacterial endocarditis |
| Vibrio cholerae | food-borne enteritis including cholera |