$$\text{IFR} = \frac{\text{Number of deaths}}{\text{Total number of infected individuals}}$$

$$\text{CFR} = \frac{\text{Number of deaths}}{\text{Number of diagnosed cases}}$$

Question 1

Which of the following best describes the term 'pathogenesis'?

Accepted Answer

The manner in which a disease develops

Question 2

A newborn delivered by cesarean section is most likely to have a microbiome dominated by which group of microorganisms?

Accepted Answer

Staphylococcus aureus

Question 3

Which of the following is an example of mutualism in the human microbiome?

Accepted Answer

E. coli in the large intestine

Question 4

According to Koch’s postulates, which step is necessary to prove that a microorganism causes a specific disease?

Accepted Answer

All of the above steps must be completed

Question 5

Which of the following is a plausible reason why Koch’s postulates may not be applicable to all infectious diseases?

Accepted Answer

Some pathogens cause disease only in humans

Question 6

A patient reports feeling tired and achy, but these symptoms are not observable by a physician. What term best describes these changes?

Accepted Answer

Symptoms

Question 7

Which equation correctly represents the calculation of infection fatality ratio (IFR)?

Accepted Answer

$$	ext{IFR} = \frac{	ext{Number of deaths}}{	ext{Total number of infected individuals}}$$

Question 8

Which of the following best describes a pandemic?

Accepted Answer

A worldwide epidemic

Question 9

A disease that develops rapidly and lasts only a short time is classified as:

Accepted Answer

Acute

Question 10

Which of the following is an example of a zoonosis?

Accepted Answer

Influenza transmitted from swine to humans

Question 11

Which of the following is NOT a mechanism by which normal microbiota protect the host?

Accepted Answer

Increasing the host’s susceptibility to infection

Question 12

Which of the following is an example of indirect contact transmission?

Accepted Answer

Touching a contaminated doorknob (fomite)

Question 13

Which of the following vectors transmits Lyme disease?

Accepted Answer

Ixodes tick

Question 14

A patient develops a secondary infection after recovering from influenza. This secondary infection is most likely caused by:

Accepted Answer

An opportunistic pathogen

Question 15

Which of the following best describes the period of illness in the progression of a disease?

Accepted Answer

Disease is most severe with maximum signs and symptoms

Question 16

Which of the following is a nonliving reservoir of infection?

Accepted Answer

Soil and water

Question 17

Which equation correctly represents the calculation of case fatality ratio (CFR)?

Accepted Answer

$$	ext{CFR} = \frac{	ext{Number of deaths}}{	ext{Number of diagnosed cases}}$$

Question 18

Which of the following is an example of vehicle transmission?

Accepted Answer

Eating food contaminated with Salmonella

Question 19

Which of the following is a plausible predisposing factor for disease?

Accepted Answer

Genetic inheritance

Question 20

A patient is diagnosed with bacteremia. Which of the following best describes this condition?

Accepted Answer

Presence of bacteria in the blood

Principles of Disease and Epidemiology: Microbiology Study Notes

Study Guide - Practice Questions