Exam 3 Lecture 23

Question 1

True or False: Most Vibrio species do not cause human infection.

Answer 1

True

Question 2

Describe the Gram Stain of Vibrio

Answer 2

Gram-negative rods (comma, curved, or straight)

Question 3

Vibrio species are ____ and have a _____ polar flagellum.

Answer 3

motile, single

Question 4

Vibrio is a ______, meaning that it can grow in ____ environments. It is typically found in _____ water.

Answer 4

halophile, salty, brackish

Question 5

Vibrio likes to grow in ____ temperatures and also likes high ______.

Answer 5

warm, salinity

Question 6

Vibrio species often feed on ____ found in shellfish.

Answer 6

chitin

Question 7

True or False: cases of Vibrio decrease during the summer.

Answer 7

False

Question 8

How many species of Vibrio are capable of causing human disease?

Answer 8

~20

Question 9

Vibrio cholerae causes ______, while illnesses caused by other diseases is called ______.

Answer 9

cholera, vibriosis

Question 10

How is cholera transmitted?

Answer 10

ingestion of contaminated food or water

Question 11

If cholera is left untreated, a patient can die from ________ in less than __ hours.

Answer 11

dehydrated, 24

Question 12

We are currently in the ___ cholera pandemic.

Answer 12

7th

Question 13

Who found out that V. cholerae is present in the intestinal contents of victims who died of cholera?

Answer 13

Filippo Pacini

Question 14

Who isolated V. cholerae in culture?

Answer 14

Koch

Question 15

True or False: Humans are the only known vertebrate hosts of V. cholerae, and it depends heavily on humans for growth

Answer 15

False - not dependent on humans (can grow in water)

Question 16

Stools shed from cholera patients have ____ V. cholerae cells/mL

Answer 16

10^9

Question 17

Which V. cholerae serogroups are known to cause widespread epidemics?

Answer 17

Serotypes O1 and O139

Question 18

Serotypes O1 and O139 produce _____ _____.

Answer 18

cholera toxin

Question 19

Where does V. cholerae colonize and multiply?

Answer 19

Small intestine

Question 20

What are the 2 main virulence factors present in V. cholerae?

Answer 20

1) Cholera toxin

2) Toxin coregulated pili (TCP)

Question 21

What is the function of TCP?

Answer 21

allows V. cholerae to colonize the small intestine

Question 22

Describe the mechanism of action of Cholera toxin

Answer 22

It enters host epithelial cells and increases levels of cAMP, and this causes host cells to release ions (Na+, K+, Cl-, HCO3-) and water is released to compensate

Question 23

Symptoms of cholera commonly appear about __ to __ days after infection.

Answer 23

2 to 3

Question 24

What percentage of people develop severe cholera?

Answer 24

5-25%

Question 25

In the initial stages, diarrhea contains intestinal contents, but the diarrhea becomes ____ and this becomes known as ____ ____ ____

Answer 25

water, rice water stool

Question 26

What's the infectious dose for cholera?

Answer 26

10^8

Question 27

True or False: Depending on your blood group, you may experience different disease severity.

Answer 27

True

Question 28

Which blood group is associated with more severe cholera?

Answer 28

O group

Question 29

Preexisting V. cholerae immunity is helpful in that patients can be _________ colonized or develop ____ illness

Answer 29

asymptomatically, mild

Question 30

Name a host factor that may lead to severe cholera

Answer 30

less acidic stomach

Question 31

What is the primary focus of cholera treatment?

Answer 31

fluid replacement

Question 32

How many liters of fluid can be lost per day from severe dehydration?

Answer 32

20 liters

Question 33

True or False: Without treatment, cholera has a fatality rate of 50%, but with fluid replacement, mortality falls under 1%

Answer 33

True

Question 34

Name an example of inadequate cholera treatment

Answer 34

not matching ongoing fluid loss w/ fluid replacement

Question 35

What may be causing delayed treatment for cholera?

Answer 35

limited cholera treatment centers

Question 36

What is used to monitor the amount of fluid loss from cholera?

Answer 36

cholera cot

Question 37

What is included in rehydration fluids?

Answer 37

sodium, potassium, chloride, bicarb, glucose

Question 38

Severe dehydration is often treated with __ _____

Answer 38

IV fluids

Question 39

________ play a secondary role in cholera treatment

Answer 39

antibiotics

Question 40

Antibiotics may play an important role in ..........

Answer 40

decreasing cholera transmission

Question 41

True or False: Many cases of Vibrio cholerae are found in the US yearly

Answer 41

false - only 7 were reported in 2014

Question 42

Where are cholera cases commonly seen?

Answer 42

developing nations that lack access to drinking water + proper sanitation (or after a humanitarian crisis that collapses infrastructure)

Question 43

Cholera is endemic in many areas of .....................

Answer 43

Africa, Latin America, South Asia