Module 7: Waterborne Diseases

Shigella

Acute bacterial diarrhea, lasts less than 2 weeks. Also known as hemorrhagic diarrhea. Signs/symptoms include fever, vomit, mucosal irritation, severe abdominal pain. Blood in stool noted.

Cryptosporidium

Diarrhea caused by a protist. Incubation of about 1 week. Often found in swimming pools. Causes acute symptoms in healthy patients; can cause chronic persistent diarrhea in AIDS patients, pregnant women or other immunocompromised patients.

Botulism

Disease caused by clostridium botulinum. Transmitted when endospores. Inhibits muscle contractions resulting in flaccid paralysis. 3 forms: food-borne, infant and wound.

Water-vectored disease

Disease caused by pathogens spread by insects that depend on water.

Salmonella

Acute bacterial diarrhea, lasts less than 2 weeks. Symptoms include vomit, diarrhea and mucosal irritation. No blood in stool noted. Severe forms cause typhoid fever.

E. coli O157:H7

Also known as enterohemorrhagic E. coli. Most virulent strain of E. coli. Symptoms include mild gastroenteritis with fever and bloody diarrhea. 10% of patients will develop hemolytic uremic syndrome.

Granulomatous amoebic meningoenchephalitis (GAM)

Caused by direct contact with Acanthamoeba species. Can be found in all water sources. Invades broken skin, conjunctiva, lungs and urogenital epithelia. Increased risk: eye injuries, contact lenses and AIDS patients. Not susceptible to chlorine; can be filtered.

Primary ameobic meningoencephalitis (PAM)

Caused by direct contact with Naegleria fowleri. Transmitted in warm bodies of fresh water. Inhaled, and invade nasal mucosa. Multiply and migrate into brain and meninges. No treatment. Prevention: chlorination or public pools.

Cyclospora

Chronic diarrhea caused by a protist. Incubation period about 1 week. Signs/symptoms include stomach cramps, bloating, fever, and muscle aches.

Hemolytic uremic syndrome

Condition caused by E. coli O157:H7. Irreversible kidney failure.

Enteroinvasive E. coli (EIEC)

Condition similar to Shigella.

Flaccid paralysis

Condition where muscles are unable to contract.

Spastic paralysis

Condition where muscles continually contract; are unable to relax.

Tetanus

Disease caused by clostridium tetani, transmitted by endospores via contaminated soil and water. Also called "Lockjaw". Causes muscles to continually contract. Preventable by administering tetanus toxoid every 10 years.

Water-based disease

Disease caused by pathogens spread through an aquatic invertebrate host.

Water-washed disease

Disease caused by pathogens spread through lack of water for personal hygiene.

Waterborne disease

Disease caused by pathogens spread through water supplies. Includes tetanus, botulism, acute diarrhea, chronic diarrhea and meningoencephalitis.

Meningoencephalitis

Inflammation of both the meninges and the brain. Caused by two amoebas: Naegleria fowleri and Acanthamoba species.

Rotavirus

Most common diarrhea infection in babies. Caused by adenovirus, norovirus and astroviruses. Incorrectly referred to as "stomach flu".

Campylobacter

Most common form of diarrhea in the US. Can lead to Guillain-Barre syndrome (GBS), a neuromuscular paralysis.

Clostridium difficle (C. diff)

Most prevalent nosocomial form of diarrhea. Superinfection caused when medications disrupt normal biota. Causes pseudomembranous colitis, blocks absorption of nutrients.

Botulinum

Neurotoxin that prevents acetylcholine from being released so muscles can contract.

Enteroaggregative E. coli (EAEC)

Only bacterial cause of chronic diarrhea, affects children and immunocompromised patients. Bacteria adheres to human cells in aggregates rather than as single cells. Causes large amounts of mucous in the gut; mucosy diarrhea.

Tetanospasmin

Toxin produced by clostridium tetani. Binds to peripheral motor neurons, spinal cord, and brain. Blocks inhibition of muscle contractions resulting in spastic paralysis.

Giardia

Transmitted through contaminated water. Zoonotic, transmitted to humans through dogs and cats. Stools have a greasy, malodorous quality; consistency of chocolate pudding. Long duration; symptoms include abdominal pain, flatulence. No fever usually present.

Enterotoxigenic E. coli (ETEC)

Traveler's diarrhea