$$\text{Prevalence} = \frac{\text{Number of cases (old + new)}}{\text{Population}}$$

$$\text{Incidence} = \frac{\text{Number of new cases}}{\text{Population}}$$

Question 1

Which term describes the study of structural and functional changes in the body caused by disease?

Accepted Answer

Pathology

Question 2

A patient presents with pain and malaise, but no observable signs. Which term best describes these changes?

Accepted Answer

Symptom

Question 3

Which of the following is NOT a way normal microbiota protect the host?

Accepted Answer

Increasing host susceptibility to infection

Question 4

What is the relationship called when one organism benefits and the other is unaffected?

Accepted Answer

Commensalism

Question 5

Which body region contains the largest numbers of resident microbiota due to its available moisture and nutrients?

Accepted Answer

Large intestine

Question 6

A disease that is constantly present in a population is referred to as:

Accepted Answer

Endemic

Question 7

Which of the following is a characteristic of an acute disease?

Accepted Answer

Symptoms develop rapidly and last only a short time

Question 8

According to Koch's postulates, what must be true for a microorganism to be identified as the cause of a disease?

Accepted Answer

All of the above must be true

Question 9

Which term describes the ability of a microorganism to cause disease by overcoming host defenses?

Accepted Answer

Pathogenicity

Question 10

What is microbial antagonism?

Accepted Answer

Competition between microbes

Question 11

Which of the following is an example of a noncommunicable disease?

Accepted Answer

Tetanus

Question 12

A disease that occurs only occasionally in a population is called:

Accepted Answer

Sporadic

Question 13

Which equation best represents the calculation of prevalence?

Accepted Answer

$$	ext{Prevalence} = \frac{	ext{Number of cases (old + new)}}{	ext{Population}}$$

Question 14

Which of the following is a mechanical factor that helps prevent microbial colonization in the eyes?

Accepted Answer

Tears and blinking

Question 15

What is the term for a disease with a period of no symptoms when the causative agent is inactive?

Accepted Answer

Latent disease

Question 16

Which of the following is NOT a factor that determines the distribution and composition of normal microbiota?

Accepted Answer

Genetic mutations in pathogens

Question 17

Which term describes the degree or extent of pathogenicity?

Accepted Answer

Virulence

Question 18

A patient is diagnosed with bacteremia. What does this mean?

Accepted Answer

Bacteria are present in the blood

Question 19

Which of the following is a real-world example of an opportunistic pathogen?

Accepted Answer

Staphylococcus epidermidis causing infection in an immunocompromised patient

Question 20

Which equation best represents the calculation of incidence?

Accepted Answer

$$	ext{Incidence} = \frac{	ext{Number of new cases}}{	ext{Population}}$$

Principles of Disease and Epidemiology: Study Notes

Study Guide - Practice Questions