$$Prevalence = \frac{\text{Number of people suffering from disease}}{\text{Total population}}$$

Question 1

Which of the following best describes the achievement of Ignaz Semmelweis in the history of medical microbiology?

Accepted Answer

He made hand washing mandatory for physicians, reducing puerperal sepsis.

Question 2

Which definition correctly describes an opportunistic pathogen?

Accepted Answer

A microorganism that does not cause disease in a normal habitat in healthy persons.

Question 3

A patient develops endocarditis after a dental procedure. Which type of infection does this scenario best illustrate?

Accepted Answer

Focal infection

Question 4

Which of the following is the correct formula for calculating the prevalence of a disease?

Accepted Answer

$$Prevalence = \frac{	ext{Number of people suffering from disease}}{	ext{Total population}}$$

Question 5

Which statement about Koch's postulates is FALSE?

Accepted Answer

They can be directly applied to all human diseases without limitations.

Question 6

A disease that develops slowly and may persist for a long time is best described as:

Accepted Answer

Chronic disease

Question 7

Which of the following best defines the infectious dose 50 ($$ID_{50}$$)?

Accepted Answer

The number of pathogens that will infect 50% of an experimental group of hosts.

Question 8

Which of the following is NOT a limitation of Koch's postulates?

Accepted Answer

All diseases are caused by a single pathogen.

Question 9

Which of the following is an example of a systemic infection?

Accepted Answer

Measles virus spreading throughout the body via blood or lymph

Question 10

Which of the following best describes the role of epidemiology in medical microbiology?

Accepted Answer

It is concerned with the distribution and prevalence of communicable diseases in populations.

Question 11

A person is infected with a virus that remains inactive for years but can reactivate and cause symptoms. This is an example of:

Accepted Answer

Latent disease

Question 12

Which of the following is the correct definition of bacteremia?

Accepted Answer

Presence of pathogens in the blood

Question 13

Which of the following is a plausible consequence of not washing hands in a hospital setting, as demonstrated by Semmelweis?

Accepted Answer

Increased rate of puerperal sepsis among patients

Question 14

Which of the following is the correct formula for calculating incidence of disease?

Accepted Answer

$$Incidence = \frac{	ext{Number of new cases during a time period}}{	ext{Population at risk during the same period}}$$

Question 15

Which of the following is an example of a secondary infection?

Accepted Answer

A bacterial infection following influenza

Question 16

Which of the following best describes virulence?

Accepted Answer

The degree of pathogenicity of members of a species; strain-specific and host-dependent

Question 17

Which of the following is NOT a member of the human microbiota that may cause disease under certain conditions?

Accepted Answer

Plasmodium falciparum

Question 18

Which of the following is a correct example of a local infection?

Accepted Answer

Pimples caused by Staphylococcus aureus

Question 19

Which of the following statements about the spectrum of infection is correct?

Accepted Answer

It is the sum of species that can be infected by a pathogenic organism.

Question 20

Which of the following is the correct definition of sepsis?

Accepted Answer

Toxic inflammatory condition caused by spread of pathogens or their toxic products

Fundamentals of Medical Microbiology: Pathogens, Disease, and Epidemiology

Study Guide - Practice Questions