Exam 1 Lecture 5

Question 1

Pathogen

Answer 1

organism that can cause disease in a particular host

Question 2

opportunistic pathogen

Answer 2

infects compromised host

• loss of specific defense mechanisms
• loss of non-specific defense mechanisms

Question 3

Rubor

Answer 3

Redness

Question 4

Calor

Answer 4

Heat/warmth at the site of inflammation

Question 5

Dolor

Answer 5

Pain

Question 6

What is the formula for finding attack rate?

Answer 6

infected / # susceptible and exposed * 100

Question 7

Primary pathogen

Answer 7

infects competent host

Question 8

Example of non-specific defense mechanism(s)

Answer 8

Skin

Question 9

Carrier state/latency

Answer 9

successful colonization WITHOUT sufficient multiplication to evoke the changes characteristic of the disease state

Question 10

What are 3 things needed for a pathogen to colonize?

Answer 10

1. adherence
2. motility
3. survival or fitness in an environment outside host

Question 11

What can pathogens use for adherence?

Answer 11

Pili

ex. PAP pili of uropathogenic E. coli

Question 12

What can pathogens use for motility?

Answer 12

Flagella and chemotaxis (ex. many enteric organisms)

• he briefly describes concept of run and tumble

Question 13

What 2 things are necessary for a pathogen to multiply?

Answer 13

1. Nutrition

2. Avoiding host immune surveillance

Question 14

What nutrient do pathogens need to multiply? How can they acquire it?

Answer 14

Iron!! However, in the human body, there is little to no free iron. Bacteria have thus evolved mechanisms to take our iron

Can be acquired through siderophores, lactoferrin/transferrin receptors

Question 15

How do pathogens avoid immune response?

Answer 15

1. Live intracellularly.
   - Live in phagolysosome through modification or blocking fusion after macrophage uptake.

-Can also break out of phagolysosome or live in cytoplasm (Listeria, Shigella)

Question 16

Salmonella has Type __ SS

Answer 16

Type 3

Also known as an “injectosome” or “molecular syringe”

Question 17

Why is the interaction between human, microbes, and diseases, not the same for all of us?

Answer 17

Depends on exposure, some people may have autoimmune diseases or other factors that may affect how their body responds to a pathogen (differing susceptibility)

Question 18

Smoking lead to…

Answer 18

1. Heart attack
2. Stroke
3. Lower respiratory tract infection
4. Cancer

Question 19

Normal functioning anatomy allows for?

Answer 19

Resistance to getting infected by opportunistic pathogens

Question 20

Inflammation involves: (5 things)

Answer 20

1. Rubor
2. Tumor
3. Calor
4. Dolor
5. Loss of function

Question 21

Infamous example of Carrier state/latency?

Answer 21

Typhoid Mary

Question 22

Virulence determinant

Answer 22

unique attributes that permit a microbe to successfully establish infection and cause subsequent disease

Question 23

Virulence

Answer 23

Quantitative measure of pathogenicity or likelihood of causing disease (experimentally determined)

Question 24

Infectivity

Answer 24

quantitative measure of a pathogen’s ability to infect another susceptible host, calculated with attack rate %

Question 25

Ways we can be resistant to infectious disease

Answer 25

Get vaccinated, limiting exposure, presence of antibiotics

Question 26

Why is it a fitness advantage to survive outside of the host?

Answer 26

To compensate for low transmission rates, increases likelihood of spreading to multiple other people

Question 27

Characteristics of phagolysosomes

Answer 27

There are oxygen radicals, low pH, toxic space for pathogens