Water-Borne Diseases Flashcards
Waterborne microorganisms can be
viruses, bacteria, protozoa, and harmful algae.
Harmful algae are
naturally occurring phytoplankton
carry toxins and accumulate in shell fish
Cause shellfish poising, respiratory issues, harm marine life.
Ex: DINO: karenia brevis
diatoms, cyano
How do they get into the water?
overland flow: agriculture, wild animals, urban runoff, sewage effluent, goes into rivers/storm drains and straight into the ocean.
Groundwater flow; septic tanks, sewage pipes, into canals, rivers.
Boaters
Naturally-occurring: vibrio species, phytoplankton.
Harmful Algal Blooms
Algal bloom: historically a bloom= increase in pop
harmful: discolored water, anoxia
toxic and harmful (oxygen depletion, gill destruction)
What species was involved in the gulf of mexico menace? and what happened?
Karenia Brevis - produced lipophilic brevetoxins
Symptoms in humans - shellfish poisoning- diarrhea,chills, headache, weakness, pain, double vision.
causes massive fish kills, blooms 20 of last 57 yes, 1991-2009
What were the mortalities of wildlife?
All of kinds of fish, birds, reptiles, mammals, no humans
How to detect hazardous microbes?
fecal pollution indications, monitor harmful algae counts, monitor shellfish for toxins,
close water to swimming/shellfish harvest is levels too high.
What is the enterococci bacteria limit for recreational contact? fecal coliform?
35/100 ml
14/100 ml
Why use indicators of pollution?
Pathogens are difficult to measure, lower concentrations, expensive time consuming, technically difficult analyses
Bacterial indicators indicate? and are?
Fecal colifom, E. coli, enterococci,
Present when pathogens are present, less expsensive, less expertise needed.
Enterococci are good indicators for fecal pollution why?
they have a greater correlation with swimming associated gastrointestinal illness
higher tolerance for salt and are useful indicators in marine environemtns
Fecal oral tranmission
microorganims tranmited in water that grow in intestines and leave the body in fecfes, water is then polluted by feces/sweage and consumed by the host
Cholera is what? How is it transmitted/ controlled? where Is it commonly found?
Caused by vibrio cholerae, typically transmitted through ingestion of contaminated water,
Large ID of cells in water
Largely restricted to developing countries
endemic in Africa and Asia, and Haiti. can be controlled by application of water treatment.
Explain the pathogenesis of cholera
V. cholarae attached to epithelial cells in the small intestine where it grows and releases enterotoxin
this enterotoxin dehydrates and cayses diarrhea.
Diagnosis, prevention and treatment of cholera
Rice water stools
public health measures
oral rehydration/electrolyte replacement
V. Vulnificus infection, where does it occur?
naturally occurs in warm coastal waters
thousands of infections each year, from shell fish
exposure due to shell fish consumption or wound infection.
shell fish/raw oystres
in 24hrs diarrhea vomiting fever
wound infection: seawater/raw shell fish drippings into cut.
Can be fatal to immunocompromised. reness swelling decreased blood pressure.
Giardia intestinalis causes
causes giardiasis, an acute gastroenteritis.
What are giardia? what do they have? what type of protist?
They are diplomonads- have two nuclei of equal size
Have mitosomes-degrenerate mitochondria.
Flagellated protist- transmitted to humans in fecally contaminated water
What is giardiasis also known as?
beaver fever.
the protist cell of giardisis does what?
produces a resting stage (cyst) that is resistant to desiccation and chemical disinfection.
After ingestion, cysts germinate and attach to the intestinal wall, causing infection symtpoms
what are the symptoms of giardisis
Foul smelling poop, cramps, sulfur burps.
many are asymtpmatic
What is cryptosporidiosis and what causes it? Explain it.
cryptospridium parvum.
it is found in surface freshwater and is highly resistant to chorline because it forms cysts.
its a protist that lives as a parasite in warm-blooded animals and produces thick-walled infective cells (oocysts) that are shed in high numbers.