Bacterial Pathogenesis and Virulence Factors

Question 1

Breach of new host defenses

Answer 1

• infectivity

Question 2

The degree of pathogenicity of a microorganism as indicated by its ability to invade the tissues of the host and cause disease

Answer 2

• Virulence

- > generally multifactorial

Question 3

Endotoxins in small or large quantities activates febrile responses causing fever/vasodilation

Answer 3

• small quantities

Question 4

What is the establishment of a population of bacteria on host’s mucosal surface?

Answer 4

• Colonization

Question 5

What term is used to describe pathogens that cause disease in immune compromised animals?

Answer 5

• opportunistic pathogens

Question 6

The process by which bacteria infects and causes disease in a host

Answer 6

• bacterial pathogenesis

Question 7

What is the penetration of host cells and tissues?

Answer 7

• Invasion

Question 8

Damage of host cells by toxins

Answer 8

• direct damage of bacteria to host

Question 9

Staphylcoccus pseudintermedius

Answer 9

• opportunist pathogen and commensal pathogen

Question 10

Organism that benefits from another organism, but does not affect this second organism positively or negatively

Answer 10

• Commensal bacteria
• > mutual relationship host and bacteria benefit
• > protective function - inhibit pathogens via competition

Question 11

What is the process by which bacteria can cause disease?

Answer 11

• bacterial pathogenesis

Question 12

Normally not a pathogen if host functioning normally, but can cause disease when given the opportunity

Answer 12

• Opportunist pathogen

- > during stress, immune suppression, etc

Question 13

Exotoxins are produced by?

Answer 13

• gram positive and negative bacteria

Question 14

In gram positive bacteria what elicits septic shock?

Answer 14

• peptidoglycan and teichoic acid

Question 15

An organized community/aggregation of bacteria that exchange products

Answer 15

• biofilm

- > occurs during transition from planktonic growth to biofilm caused by environmental condition change

Question 16

When are endotoxins released?

Answer 16

• during bacterial cell lysis and death

Question 17

Organism that invades or establishes itself in tissues that have been infected by a primary agent

Answer 17

• secondary pathogen

Question 18

Toxin that destroys nerve cells

Answer 18

• neurotoxin

Question 19

Organism that must infect host in order to survive and spread from one host to another

Answer 19

• obligate pathogen

Question 20

Stimulate host immune response

Answer 20

• indirect damage of bacteria to host

Question 21

Toxin produced in and affects the intestines

Answer 21

• enterotoxin

Question 22

Endotoxins in small or large quantities activates endotoxic shock

Answer 22

• large quantities

Question 23

Are endotoxins or exotoxins proteinaceous/enzymes

Answer 23

• exotoxins

Question 24

What step in bacterial pathogenesis is necessary to avoid innate host defense mechanism?

Answer 24

• Adhesion

Question 25

What are the effects of exotoxins?

Answer 25

• most are potent toxins and cause acute illness

Ex: Anthrax, botulism and cholera

Question 26

Prevents attachment of antibody to antigen and inhibits phagocytosis

Answer 26

• bacteria capsule

- > makes cell larger and harder to engulf

Question 27

Toxin that destroys cells

Answer 27

• cytotoxin

Question 28

The toxic component of LPS in endotoxins

Answer 28

• Lipid A

Question 29

Toxin produced in and affects the kidney

Answer 29

• nephrotoxin

Question 30

What are the essential nutrients for bacterial growth?

Answer 30

• IRON, oxygen and suitable temps

Question 31

Endotoxins are a component of gram positive or gram negative bacteria?

Answer 31

• gram negative bacteria

- > component of the bacterial cell wall

Question 32

What term is used to describe pathogens that cause disease in healthy animals?

Answer 32

• primary pathogens

Question 33

What is commensal bacteria? Give examples

Answer 33

• mutual host/bacteria relationship where both benefit

Ex: E. coli and Staphylococcus pseudintermedius

Question 34

Organism that can initiate disease on its own

Answer 34

• primary pathogen

Question 35

When are exotoxins released?

Answer 35

• by intact living bacteria and are secreted into the surrounding environment, injected into host cell, or enter via invasion of host cell

Question 36

What is the ability of a pathogen to harm the host?

Answer 36

• virulence