Cholera Flashcards
which pathogen causes cholera?
bacteria -> v. (vibrio) cholerae
what kind of disease does the cholera bacteria cause? what is the main symptom?
gastroenteritis, watery diarrhea
why can cholera be lethal?
dehydration and electrolyte imbalances
what kind of bacteria is v. cholerea: gram + or -? shape? does it have a flagella?
gram negative, curved with flagella
via what route is cholera transmitted?
fecal -> oral
- consuming untreated sewage water
- poor hygiene
consumption of what can lead to cholera?
consuming untreated sewage water (or anything that comes in contact with it, e.g. raw or undercooked fish)
cholera: who are particularly at risk for a severe infection?
people with
- low gastric acidity
- 0-blood type
what does v. cholera do in the stomach? (2 things) why?
shuts down protein production to conserve energy
1) conserve energy & nutrients
2) survives acidic environment
what does the v. cholerae do with its flagella in the intestine? (3 things)
1) move towards intestinal walls 2
2) propel through mucus layer
3) attach to villi
what does v. cholerae do when on top of the villi of endothelial cells? (2 things)
multiply, secrete toxins
do cholera bacteria themselves enter enterocytes? do their toxins enter enterocytes?
bacterium doesn’t, but toxins do!
do all cholera bacterial strains cause symptoms? what does it need to produce to cause symptoms?
no
it needs to produce cholera enterotoxin
what is the effect of cholera enterotoxins on the enterocyte wall? (2 effects)
1) production of more chloride channels -> more secretion of chloride into the lumen
2) inhibit channel that let sodium & chloride into cells
what is the effect of more chloride & sodium inside the intestinal lumen?
attracts water -> diarrhea
what are the 2 main symptoms of cholera?
watery diarrhea & vomiting
