Water borne diseases are caused by pathogenic microganism that are transmited in contaminated water. Commonly results during bathing, washing, drinking and preparation of food. This causes 1.8 million deaths world wide.
Infections by type of pathogen
Disease and Transmission Microbial Agent Sources of Agent in Water Supply General Symptoms
Amoebiasis (hand-to-mouth) Protozoan (Entamoeba histolytica) (Cyst-like appearance) Sewage, non-treated drinking water, flies in water supply Abdominal discomfort, fatigue, weight loss, diarrhea, bloating, fever
Cryptosporidiosis (oral) Protozoan (Cryptosporidium parvum) Collects on water filters and membranes that cannot be disinfected, animal manure, seasonal runoff of water. Flu-like symptoms, watery diarrhea, loss of appetite, substantial loss of weight, bloating, increased gas, nausea
Cyclosporiasis Protozoan parasite (Cyclospora cayetanensis) Sewage, non-treated drinking water cramps, nausea, vomiting, muscle aches, fever, and fatigue
Giardiasis (fecal-oral) (hand-to-mouth) Protozoan (Giardia lamblia) Most common intestinal parasite Untreated water, poor disinfection, pipe breaks, leaks, groundwater contamination, campgrounds where humans and wildlife use same source of water. Beavers and muskrats create ponds that act as reservoirs for Giardia. Diarrhea, abdominal discomfort, bloating, and flatulence
Microsporidiosis Protozoan phylum (Microsporidia), but closely related to fungi Encephalitozoon intestinalis has been detected in groundwater, the origin of drinking water  Diarrhea and wasting in immunocompromised individuals.
Disease and species Microbial Agent Sources of Agent in Water Supply General Symptoms
Schistosomiasis (immersion) Members of the genus Schistosoma Fresh water contaminated with certain types of snails that carry schistosomes Blood in urine (depending on the type of infection), rash or itchy skin. Fever, chills, cough and muscle aches
Dracunculiasis (Guinea Worm Disease) Dracunculus medinensis Stagnant water containing larvae, generally in parasitised Copepoda Allergic reaction, urticaria rash, nausea, vomiting, diarrhea, asthmatic attack.
Taeniasis Tapeworms of the genus Taenia Drinking water contaminated with eggs Intestinal disturbances, neurologic manifestations, loss of weight, cysticercosis, Coenurosis
Fasciolopsiasis Fasciolopsis buski Drinking water contaminated with encysted metacercaria GIT disturbance, diarrhea, liver enlargement, cholangitis, cholecystitis, obstructive jaundice.
Hymenolepiasis (Dwarf Tapeworm Infection) Hymenolepis nana Drinking water contaminated with eggs Abdominal pain, severe weight loss, itching around the anus, nervous manifestation
Echinococcosis (Hydatid disease) Echinococcus granulosus Drinking water contaminated with feces (usually canid) containing eggs Liver enlargement, hydatid cysts press on bile duct and blood vessels; if cysts rupture they can cause anaphylactic shock
Ascariasis Ascaris lumbricoides Drinking water contaminated with feces (usually canid) containing eggs Mostly, disease is asymptomatic or accompanied by inflammation, fever, and diarrhea. Severe cases involve Löffler’s syndrome in lungs, nausea, vomiting, malnutrition, and underdevelopment.
Enterobiasis Enterobius vermicularis Drinking water contaminated with eggs Peri-anal itch, nervous irritability, hyperactivity and insomnia