$$\text{Incidence} = \frac{\text{new cases}}{\text{population}} \times 100,000$$

Question 1

Which of the following best describes an opportunistic pathogen?

Accepted Answer

A pathogen that only causes disease when the host's immune system is weakened.

Question 2

Which equation correctly calculates the incidence rate of a disease in a population?

Accepted Answer

$$	ext{Incidence} = \frac{	ext{new cases}}{	ext{population}} 	imes 100,000$$

Question 3

A patient develops symptoms of a disease two days after being exposed to a pathogen. Which stage of infectious disease is this?

Accepted Answer

Prodromal phase

Question 4

Which of the following is a characteristic of a chronic carrier?

Accepted Answer

They may remain asymptomatic for long periods but can still spread the pathogen.

Question 5

Which of the following is an example of vehicle transmission?

Accepted Answer

Drinking water contaminated with Vibrio cholerae

Question 6

What is the primary difference between an epidemic and a pandemic?

Accepted Answer

A pandemic spreads to numerous countries, while an epidemic is limited to a particular region.

Question 7

Which of the following factors would most likely increase the prevalence rate of a chronic disease?

Accepted Answer

Effective treatments that help people live longer with the disease

Question 8

Which of the following is a direct contact transmission route?

Accepted Answer

Touching, kissing, or sexual contact

Question 9

Why is quarantine most effective when someone has been exposed to a contagious disease but is not yet showing symptoms?

Accepted Answer

It helps stop the infection from spreading to others before symptoms appear.

Question 10

Which of the following best defines morbidity?

Accepted Answer

Existence of disease in a population

Question 11

A new strain of influenza virus appears and spreads rapidly because most people have little to no immunity. What type of disease is this?

Accepted Answer

Emerging disease

Question 12

Which of the following is NOT a goal of epidemiology?

Accepted Answer

To increase the prevalence of infectious diseases

Question 13

Which of the following is an example of a fomite?

Accepted Answer

A contaminated phone

Question 14

Which stage of infectious disease is characterized by the body fighting off the infection and symptoms beginning to fade?

Accepted Answer

Period of decline

Question 15

Which of the following is a measure to prevent community-acquired infections?

Accepted Answer

Vaccination and avoiding close contact with sick people

Question 16

Which of the following equations correctly calculates the prevalence rate?

Accepted Answer

$$	ext{Prevalence} = \frac{	ext{total existing cases}}{	ext{total population}} 	imes 100,000$$

Question 17

Which of the following is true about herd immunity?

Accepted Answer

It protects people who cannot be vaccinated by reducing disease spread.

Question 18

Which of the following is a vector transmission route?

Accepted Answer

Mosquito carrying Plasmodium from one host to another

Question 19

Which of the following best describes an endemic infection?

Accepted Answer

Infections routinely detected in a population or region

Question 20

A person who has recovered from a disease but continues to carry and spread the pathogen without symptoms is called:

Accepted Answer

Chronic carrier

Microbiology Study Guide: Epidemiology, Disease Transmission, and Infection Types

Study Guide - Practice Questions