Table 3.

Classification of human pathogens based on damage as a function of immune responsea

ClassPathogenDamage as a magnitude of the immune responseb
WeakIntermediateStrong
1Legionella pneumophilaLegionnaire’s diseaseNoneNone
Pneumocystis cariniiPneumoniaNoneNone
Pseudallescheria boydiiInvasive sinusitis, pneumoniaNoneNone
Staphylococcus epidermidisVascular infectionsNoneNone
2AdenovirusPneumonia, disseminated infectionUpper respiratory infection, diarrhea, hemorrhagic cystitisNone
AlphavirusesEncephalitisEncephalitisNone
Bacillus anthracisAnthraxAnthraxNone
Blastomyces dermatitidisDisseminated blastomycosisPneumoniaNone
Bordetella pertussisSecondary pneumoniaPertussisNone
Borrelia burgdorferiPersistence of infection with arthritis and meningitisLyme diseaseNone
Brucellaspp.BrucellosisBrucellosisNone
Candida spp.Mucocutaneous candidiasisVaginal candidiasisNone
Clostridium tetaniTetanusTetanusNone
Clostridium botulinumBotulismBotulismNone
Corynebacterium diphtheriaeDiphtheriaDiphtheriaNone
Cryptococcus neoformansMeningoencephalitisPrimary complex in lung, pneumonia, meningoencephalitisNone
Cryptosporidium spp.Chronic diarrheaDiarrheaNone
Ebola virusHemorrhagic feverHemorrhagic feverNone
Entamoeba histolyticaAmebiasisAmebiasisNone
Francisella tularensisDisseminated infectionTularemiaNone
Group B streptococcusInvasive infectionPuerperal sepsisNone
Haemophilus influenzae type bDisseminated infectionUpper respiratory infection, meningitisNone
Hemophilus ducreyiDisseminated infectionChancroidNone
Hepatitis A virusHepatitisHepatitisNone
JC virusHemorrhagic cystitis, ureteral stenosis, progressive multifocal leukoencephalopathyAsymptomaticNone
Listeria monocytogenesListeriosisListeriosisNone
Molluscum virusDisseminated molluscumMolluscum contagiosumNone
Neisseria gonorrhoeaeDisseminated infectionUrethritis, PIDNone
Neisseria meningitidisMeningococcemia carrier stateMeningitisNone
Paracoccidioides brasiliensisDisseminated infectionPneumoniaNone
ParvovirusAplastic and chronic anemiaErythema infectiosumNone
Plasmodiumspp.MalariaMalariaNone
Pseudomonas aeruginosaPneumonia, systemic infectionDiarrheaNone
RhinovirusUpper respiratory infectionUpper respiratory infectionNone
Rickettsia rickettsiiRocky mountain spotted feverRocky mountain spotted feverNone
Rochalimaeaspp.Bacillary angiomatosisBacillary angiomatosisNone
RotavirusDiarrheaDiarrheaNone
Streptococcus pneumoniaePneumonia, meningitis, pneumococcal sepsisPneumonia, meningitisNone
Toxoplasma gondiiToxoplasmosisCervical lymphadenopathyNone
Trichomonas vaginalisTrichomoniasisTrichomoniasisNone
Varicella-zoster virusDisseminated infectionVaricella, dermatomal zosterNone
Vibrio choleraDiarrheaDiarrheaNone
Yersinia pestisSepticemic, pneumonic and meningeal plagueBubonic plagueNone
3Chlamydia pneumoniaePneumoniaPneumoniaAsthma(?), atherosclerosis(?)
Coccidioides immitisDisseminated coccidioidomycosisPneumoniaErythema nodosum, erythema multiforme
CytomegalovirusPneumonitis, hepatitis, retinitisMononucleosisGuillain-Barré syndrome
Escherichia coliO157:H7DiarrheaDiarrheaHemolytic uremic syndrome
Epstein-Barr virusHairy leukoplakia, lymphoproliferative disordersMononucleosisBurkitt’s lymphoma, nasopharyngeal carcinoma
Streptococcus pyogenesScarlet fever, erysipelas, toxic shock syndromeScarlet fever, erysipelas, toxic shock syndromeRheumatic fever glomerulonephritis
Hepatitis B virusChronic infectionHepatitisHepatocellular carcinoma
Herpes simplex virus 2Genital herpes, disseminated herpesGenital herpes, neonatal herpes, encephalitisCervical cancer
Herpes simplex virus 1Gingivostomatitis, esophagitis, pneumonitisGingivostomatitis, encephalitisOropharingeal carcinoma
Histoplasma capsulatumDisseminated histoplasmosisPrimary complex in lungFibrosing mediastinitis
Human immunodeficiency virusAIDSAIDSSjogren-like syndrome(?)
Influenza virusInfluenzaInfluenzaReye syndrome(?), Guillain-Barré syndrome, transverse myelitis
Leishmania spp.Visceral leishmaniasisLeishmaniasisGlomerulonephritis
Measles virusSevere measles, giant cell pneumoniaMeaslesAtypical measles, SSPE
Mycobacterium tuberculosisPulmonary and disseminated tuberculosisPrimary complex in lung, latent infectionScar carcinoma, constrictive pericarditis, fibrosing mediastinitis
Papilloma virusWarts, condyloma acuminata, neoplasiaWarts, condyloma acuminata, neoplasiaNeoplasia
Respiratory syncytial virusSevere pneumoniaPneumonia, bronchiolitisHyperactive airways?
Salmonella spp.Salmonellosis chronic carrierEnteric feverReiter syndrome
Staphylococcus aureusSuppurative infections, toxic shock syndrome, endovascular infectionsSuppurative infections, endovascular infectionsToxic shock syndrome
Treponema pallidumAccelerated coursePrimary and secondary syphilisObliterative endarteritis, tertiary syphilis
Yersinia enterocoliticaSepticemiaEnterocolitisReactive polyarthritis
4Aspergillus spp.Invasive aspergillosisNoneAllergic sinusitis, Farmer’s lung
Vaccinia virusVaccinia necrosumNoneEncephalitis
5Mycoplasma pneumoniaePneumoniaPneumoniaRaynoud’s phenomenon, Guillain-Barré, erythema multiforme
Chlamydia trachomatisTrachoma, perinatatal infections, lymphogranulama venereumTrachoma, perinatatal infections, lymphogranulama venereumReiter’s syndrome, infertility, ectopic pregnancy, spontaneous abortions
Mumps virusMumpsMumpsDiabetes(?), encephalitis
Campylobacter jejuniDiarrheaDiarrheaReiter’s syndrome
PoliovirusPoliomyelitisPoliomyelitisPostmyelitis syndrome
Shigellaspp.DiarrheaDiarrheaReiter’s syndrome
Trematodaspp.SchistosomiasisSchistosomiasisPortal and pulmonary hypertension, bladder neoplasia
Trypanosomaspp.TrypanosomiasisTrypanosomiasisCardiomyopathy
6Helicobacter pyloriNone associatedNone associatedGastric gastritis, carcinoma, lymphoma
  • a Not a complete list of all pathogens.

  • b The terms weak, intermediate, and strong include qualitative and quantitative aspects of the host response. For examples of weak and strong responses see Table 2. The intermediate category is the most common type of response in a healthy population and the conditions listed under this category can occur in healthy individuals. SSPE, subacute sclerosing panencephalitis; PID, pelvic inflammatory disease.