The Vibrios

Question 1

Classify the vibrios enteric bacteria?

Answer 1

Curved, gram negative rods

Question 2

Do the vibrios enteric bacteria grow on bile salts agar in vitro?

Answer 2

Yes, they do

Question 3

Cholera is known for causing epidemics and pandemics throughout history- What’s the best way to prevent against cholera infection?

Answer 3

Hygiene- purify food and water. There is also a modestly effective vaccine for epidemics.

Question 4

What are the reservoirs for cholera?

Answer 4

Humans and ocean microbial communities

Question 5

What bodies of water are the main source of cholera reservoirs?

Answer 5

Indian Ocean and Gulf of Mexico

Question 6

What form is the source of genetic diversity for cholera?

Answer 6

“Planktonic” ocean form

Question 7

How is cholera transmitted?

Answer 7

Fecal-oral route

Question 8

Cholera: High or low infectious dose?

Answer 8

High Infectious Dose

Question 9

What two virulence factors help cholera to colonize the small intestine?

Answer 9

Mucinase and toxin-coregulated pilus

Question 10

Does cholera secrete an enterotoxin?

Answer 10

Yes, choleragen- similar to toxin secreted by ETEC(noninvasive E. coli)

Question 11

What is the role of cholera’s AB subunit?

Answer 11

It’s a signal transduction alterer

Question 12

What kind of diarrhea does cholera cause?

Answer 12

Massive watery diarrhea-> Rice Water Stool (both intercellular and interstitial)

Question 13

The choleragen gene is carried by what?

Answer 13

The lysogenic bacteriophage CTX

Question 14

What are O1 and O139?

Answer 14

Markers of infection by lysogenic bacteriophage CTX

Question 15

Do non-CTX V. cholerae strains cause disease?

Answer 15

They cause sporadic, mild disease

Question 16

Is bacteremia commonly seen or rarely seen with cholera infection?

Answer 16

Rarely seen (Remember it’s non-invasive)

Question 17

What is the most common cause of morbidity and mortality from cholera infection?

Answer 17

Dehydration and electrolyte imbalance (acidosis, loss of potassium)

Question 18

How do you diagnose interstitial dehydration?

Answer 18

Skin-tenting pinch test

Question 19

How do you treat dehydration resulting from cholera infection?

Answer 19

IV Lactated Ringers Solution (not just saline–>acidosis)

Question 20

What drug helps shorten the course of v. cholerae or v. parahaemolyticus?

Answer 20

Doxycycline, rehydration is also important

Question 21

Non-cholera vibrios (v. parahaemolyticus and v. vulcanis) are associated with what conditions?

Answer 21

Gastroenteritis and rapidly progressing cellulitis

Question 22

What causes infection of the non-cholera vibrios (v. parahaemolyticus and v. vulcanis)?

Answer 22

Eating or handling raw shellfish

Question 23

What is the reservoir for non-cholera vibrios (v. parahaemolyticus and v. vulcanis)?

Answer 23

Ocean water, they’re halophiles

Question 24

What are factors that predispose you to complications after infection by non-cholera vibrios (v. parahaemolyticus and v. vulcanis)?

Answer 24

Liver disease, immunodeficiency, iron overload

Question 25

How do you diagnose cellulitis?

Answer 25

Exam (rapid progression, hemorrhagic bullae, sea-water exposed injury), Gram stain, and Culture

Question 26

How do you treat cellulitis caused by the non-cholera vibrios (v. parahaemolyticus and v. vulcanis)?

Answer 26

Dual antibiotics and surgical care