Table 7.1.
Pathogenic agents for waterborne diseases.
| Group | Pathogen | Diseases caused | Relative infectivity | Resistance to disinfection |
|---|---|---|---|---|
| Virus | Enteroviruses (polio, echo, coxsackie) | Meningitis, paralysis, rash, fever, myocarditis, respiratory disease, and diarrhea | High | Moderate |
| Hepatitis A and E human caliciviruses | Infectious hepatitis | High | Moderate | |
| Norwalk viruses, Sapporo, rotavirus | Diarrhea/gastroenteritis | High | Moderate | |
| Astroviruses | Diarrhea | High | Moderate | |
| Adenovirus | Diarrhea (types 40 and 41), eye infections, and respiratory disease | High | Moderate | |
| Reovirus | Respiratory and enteric | High | Moderate | |
| Putative enteropathogens (coronavirus, enterovirus, torovirus, parvovirus, and reovirus) | Causal relationship is still not proven | High | Moderate | |
| Bacteria | Salmonella | Typhoid and diarrhea | Low | Low |
| Shigella, Yersinia enterocolitica | Diarrhea | High | Low | |
| Campylobacter | Diarrhea-leading cause in foodborne outbreaks | Moderate | Low | |
| Escherichia coli O157:H7 and other certain strains | Bloody diarrhea (hemorrhagic colitis) and renal failure (hemolytic uremic syndrome) in humans | High | Low | |
| Legionella pneumophila | Legionnaires (acute purulent pneumonia) and Pontiac fever (a self-limiting nonpneumonic disease) | Moderate | Moderate | |
| Pseudomonas aeruginosa | Pulmonary disease, skin infection | Low | Low | |
| Vibrio cholerae | Cholera | Low | Low | |
| Protozoa | Naegleria | Amebic meningoencephalitis | Moderate | Low |
| Entamoeba histolytica | Amebic dysentery | High | High | |
| Giardia lamblia | Giardiasis (chronic diarrhea) | High | High | |
| Cryptosporidium parvum | Cryptosporidiosis (acute diarrhea, fatal for immunocompromised individuals) | High | High | |
| Cyclospora | Diarrhea | High | High | |
| Microsporidia (Enterocytozoon spp., Encephalitozoon spp., Septata spp., Pleistophora spp., Nosema spp.) | Chronic diarrhea and wasting, pulmonary, ocular, muscular, and renal disease | |||
| Toxoplasma gondii | Toxoplasmosis | High | High | |
| Acanthamoeba spp. | Keratitis, encephalitis | High | Low | |
| Cyanobacteria | Microcystis, Anabaena, Aphantiomenon | Diarrhea from ingestion of the toxins; these organisms produce microcystin; toxin is implicated in liver damage | ||
| Helminths | Ascaris lumbricoides | Ascariasis | ||
| Trichuris trichiura | Trichuriasis (whipworm) | |||
| Taenia saginata | Beef tapeworm | |||
| Schistosoma mansoni | Schistosomiasis (affecting the liver, bladder, and large intestine) |