Chapter 13: Medical Microbiology

Question 1

What is the definition of epidemiology?

Answer 1

Epidemiology is the study of disease within populations.

Question 2

What are the four tenets of epidemiology?

Answer 2

The four tenets of epidemiology are the cause of disease, methods of disease spread, transmission patterns, and the effects of disease on a population.

Question 3

What is the definition of transmission?

Answer 3

Transmission is the spread of disease from one host to another.

Question 4

How can we describe direct contact in an epidemiological sense?

Answer 4

Direct contact occurs when disease is spread via physical contact between two organisms.

Question 5

What is a vector?

Answer 5

A vector is a living organism that serves as an intermediate for the spread of disease (ticks, mosquitos).

Question 6

Define sterilization.

Answer 6

Sterilization is any process in which all pathogens are killed.

Question 7

Define disinfection.

Answer 7

Disinfection is any process in which some, but not all pathogens are killed.

Question 8

What is an antiseptic?

Answer 8

An antiseptic is a disinfectant that is designed for use on bodily tissue.

Question 9

What is active immunity?

Answer 9

Active immunity is acquired from a prior infection, and involves the creation of memory cells.

Question 10

How is a vaccine characterized?

Answer 10

Vaccines transport fragments of attenuated or dead pathogens to stimulate immune responses.

Question 11

What is passive immunity?

Answer 11

Passive immunity involves the transfer of previously existing antibodies to an organism.

Question 12

Why may some antibacterial agents not work on all bacteria?

Answer 12

Some antibacterial agents target bacteria with a different gram composition, and may not work on the opposite end.

Question 13

What is the difference between a bactericidal agent and a bacteriostatic agent?

Answer 13

Bactericidal agents kill bacteria, and bacteriostatic agents prevent bacteria from multiplying.

Question 14

When is a bacteriostatic agent not recommended for a patient?

Answer 14

The patient must have a strong enough immune system to kill the bacteria, so immunocompromised patients will not benefit from a bacteriostatic agent.

Question 15

What are three ways that antibiotic resistance can manifest?

Answer 15

1. pumping out the antibiotic
2. translating enzymes to inactivate antibiotics
3. mutating DNA to render antibiotic ineffective

Question 16

Why are antiviral agents often less effective than antibacterial agents?

Answer 16

Antiviral agents cannot target viruses as effectively, as they are non-living and the host cell must be preserved.

Question 17

What do antiviral agents specifically do?

Answer 17

Antiviral agents interrupt DNA replication and inhibit proteases.

Question 18

What part of a fungal cell to antifungal agents usually target?

Answer 18

Antifungal agents usually target fungal cell walls, and do not affect human cells.

Question 19

What does fluconazole do?

Answer 19

Fluconazole prevents the formation of ergosterol, which is an integral part of fungal cell membrane integrity.

Question 20

Why are antiparasitic agents so different in their mechanisms of action?

Answer 20

Antiparasitic agents target specific parasites, which have incredible physiological diversity.