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45 Cards in this Set
- Front
- Back
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where is cholera found |
in the water!!!
causes SUDDEN onset (viral needed some time in the small intestine to grow) afebrile watery diarrhea. can kill you |
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what GI disease is common after a disaster
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cholera
can kill |
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how does cholera toxin cause disease
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colonize sm intestine
**WONT damge the tissue **TONS of watery diarrhea- rice water stool *rapid depletion of fluids/electrolytes can lead to hypovolumic shock, metabolic acidosis, death 1L/1 Hr |
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with cholera do we have lots of diarrhea
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OMG YA!!!!
IL/Hour Death due to dehydration. tx pts by pumping them full of fluid. bc this is a BACTERIA can also use AB pts will live if they can be rehydrated, self limited |
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what is the onset of cholera
what is the incubaction |
sudden
1-5 days **loose IL/hour, needs to be replaced. looks like washer woman hands bc hypovolumic. associated with diseasters. kills TONS |
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what are the serogroups of cholera
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1. O1- classic epidemic, "El tor"
2. O139- can cause disease if you had previous O1 infection (normally cholera infection grants immunity) |
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whats the ID/biochem of cholera
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Gram - vibrio (bent rod)
OXIDASE + motile, anerobe, no spores |
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whats EL tor
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the classic O-1 sreotype cholera
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whats O130
whats O1 |
CHOLERA strains
O139- new found cholera, will cause didsease if you had classic O1 cholera previously O1- classic, El tor. classic epidemic cholera (after disaster is common, bad water source) O stands for the O AG associated with endotoxin (gram -) |
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whats the main cholera toxin
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enteroroxin, cholera toxin *sholeragen). phage encoded. AB toxin
A- active. increase cAMP --> hyperscretion of electrolytes and diarrhea B- binding: binding protein **another important virulence is toxin coregulated pilus- attachment to host |
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what is the cholera toxin
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aka choleragen, its an AB toxin that is encoded on phage. associated with O1 AND O139
A- Active: causes increased cAMP to cause hypersecretion of water nad electrolytes B: binding protein |
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which toxin acts by increaseing cAMP which increases water and electrolyte secretion (diarrhea)
which one binds to neighbors and intoxicates them to secrete Ca |
cholera
rotavirus |
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where is the cholera toxin (the one that increases cAMP)
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in teh CTX moble gene element
on a phage CTX virus receptor also has a toxin corregulated pilus virulence factor for attachment to host. this is on PAI |
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whats CTX
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its a mobile genetic element, it is a filamentous virus related to M13
it codes for the cholera toxin. the toxin genes are acquired via lysogenic conversion CTX is located in the pathogenicity island |
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what VPI
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vibrio pathogenicity island
area on chromosome where virulence genes are- CTX is here also tcp, a subunit A product (part of virion coat) |
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The entire pathogenicity island, VPI, is the genome of...
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another filamentous
bacteriophage, VPI phage VPI cirion coat is made of hte tcp gene subunit A gene product |
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what happens with lysogenic conversion in cholera
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2 lysogenic conversins are required to obtain a virulent cell
its a unique process in which a Virus VPI delivers virulence via lysogenic conversion. THEN we get ANOTHER lysogenic conversion. one viru spromotes infection by another virus |
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how id cholera dx
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hard, not easy to find in the poo. look for motility
grows in poo but in the lab it needs special TCBS agar (thiosulfate citrate bile salts) bile inhibots the normal flora OXIDASE + |
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what grows on TCBS agar
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cholera
oxidase + |
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can you have a cholera infection that causes diarrhea but NOT cholera
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its possible!
the cholera needs to have the CTX cholera toxin, if it doesnt have the phage it wont cause cholera oxidase + |
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how do you tx cholera
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replace fluid/electrolytes
Mild disease needs oral rehydration but with more severe needs IV Can also tx with AB- if its NOT an O1 strain or TRUE severe cholera not spread person to person, more spread from water |
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when might you use AB to tx cholera
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when its caused by NON O1 OR severe true cholera
Antibiotics may be used to shorten course of more severe true cholera disease. BUT there will still be fluid secretion bc the TOXIN is still active even though the bug is dead |
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what is the spidemic strain of cholera
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O1 El Tor
CONTAMINATED WATER. not really person to person BUT as the bug passes through the GI it gets TONS more infectious and can get into the water |
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what happens as cholera comes through the GI
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it gets way more infectious!
not person to person spread BUT if they poo it into the waater hte water will carry it |
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are humans resevoirs for cholera
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ya, not person to person spread but can leave the GI and is more infectious
occurs in the US from boat travel |
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do we get cholera in US
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yep, not usually endemic
**common spread from boat travel |
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what happened in haiti
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earthquake caused cholera, infectioed water
V cholera )1, El Tor |
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who has a more severe form of cholera
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blood type O
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is cholera sensitive to acid/
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yep! if you have low acid you will get more severe disease
More severe disease in blood group O also less acid---> more disease |
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how can we prevent cholera
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VACCINE!!!
short lived immunity only, killed organism/toxoid Not reccommended for travelers to regions where the disease is endemic CONTROL SEWAGE prophylactic tetracycline for ppl traveling to cholera regions |
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is there a cholera vaccien
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yep, gives short lived immunity
NOT reccomended to travelers to regions in which the disease is endemic **killed organism/toxoid |
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if we control sewage what disease is greatly reduces
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cholers
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what is el nino linked to
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cholera
**currents spread organisms in the ocean |
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whats V parahaemolyticus
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classic food poision, think sea food
Gastro enteritis, mild form of cholera like sx 2-3 days WOUND INFECTIONS also |
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what vibro is associated with seafood food poision and wound infections
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parahaemolyctious
**seasonal, recedes in the winter |
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whats the disease associated with the US gilt coast
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vibrio cholera
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what potential is there when we have a live attenuated cholera vaccine
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can get toxic genes, lysogenic conversion
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whats hte vibri that is more common in the summer
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parahaemolyticus
**human infection with raw or undercooked shellfiush- NEEDS to be refridgerated. less instances in the winter when it is cold OXIDASE + same as cholera, also grows on TCBS |
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V paraheamolyticus is what biochem? what does it grow on
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oxidase + (like cholera)
TCBS- WONT FERMENT SUCROSE!!! also same as cholera |
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why are oysters bad
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Vibrio vilnificus
**more disease in summer/warm months **MOST important pathogenic vibrio in US **found in coastal marine water and estuary waters |
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what is the most important vibrio in US
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vulnificus
**the one associated with oysters **can also be in wound infections **can also cause sepsis |
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does V vulnificus spread from humans
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nope!
serious threat to ppl with underlying conditions |
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sepsis is associated with what vibrio
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vulvinificus
**the oyster one pl must have eaten the oyster (not just in water as can be seen in wound infections) more common in ppl with live prblm and increased Fe deposition Tx with tetracuycline |
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whats hte food poision like sx you get from eating raw oysters
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acite self limited, RAW oyster
**V vulnificous |
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tell me what agar is ised for VIBRIO
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TCBS
needs NaCl colonies gow green WONT ferment sucrose Oxidase + bile salts int eh agar kills normal flora |
