Deck 14: Principles of Disease and Epidemiology

Question 1

Focal infections initially start out as

A)sepsis.
B)bacteremia.
C)local infections.
D)septicemia.
E)systemic infections.

Answer 1

C

Question 2

Which of the following is a fomite?

A)water
B)droplets from a sneeze
C)pus
D)insects
E)a hypodermic needle

Answer 2

E

Question 3

Which of the following statements about healthcare-associated infections is FALSE?

A)They occur in compromised patients.
B)They may be caused by opportunists.
C)They may be caused by drug-resistant bacteria.
D)They may be caused by normal microbiota.
E)The patient was infected before hospitalization.

Answer 3

E

Question 4

Koch observed Bacillus anthracis multiplying in the blood of cattle.What is the condition specifically called when bacteria are multiplying in the blood?

A)bacteremia
B)focal infection
C)local infection
D)septicemia
E)systemic infection

Question 5

A healthcare-associated infection (traditionally known as a nosocomial infection)is

A)always present,but is inapparent at the time of hospitalization.
B)acquired during the course of hospitalization.
C)always caused by medical personnel.
D)only a result of surgery.
E)always caused by pathogenic bacteria.

Question 6

Which of the following is NOT a reservoir of infection?

A)a sick person
B)a healthy person
C)a sick animal
D)a hospital
E)None of the answers is correct;all of these can be reservoirs of infection.

Question 7

The major significance of Robert Koch's work is that

A)microorganisms are present in a diseased animal.
B)diseases can be transmitted from one animal to another.
C)microorganisms can be cultured.
D)microorganisms cause disease.
E)microorganisms are the result of disease.

Question 8

Which of the following diseases is NOT spread by droplet infection?

A)botulism
B)tuberculosis
C)measles
D)the common cold
E)diphtheria

Question 9

A commensal bacterium

A)does not receive any benefit from its host.
B)is beneficial to its host.
C)may also be an opportunistic pathogen.
D)isn't capable of causing disease in its host.
E)always causes disease in its host.

Question 10

Transient microbiota differ from normal microbiota in that transient microbiota

A)cause diseases.
B)are found in a certain location on the host.
C)are always acquired by direct contact.
D)are present for a relatively short time.
E)never cause disease.

Question 11

Which of the following definitions is INCORRECT?

A)endemic: a disease that is constantly present in a population
B)epidemic: a disease that is constantly present across the world
C)pandemic: a disease that affects a large number of people in the world in a short time
D)sporadic: a disease that affects a population occasionally
E)incidence: number of new cases of a disease

Question 12

Which of the following statements is TRUE?

A)Both members are harmed in a symbiotic relationship.
B)Members of a symbiotic relationship cannot live without each other.
C)A parasite is not in symbiosis with its host.
D)Symbiosis always refers to different organisms living together and benefiting from each other.
E)At least one member must benefit in a symbiotic relationship.

Question 13

Which one of the following does NOT contribute to the incidence of healthcare-associated infections?

A)antibiotic resistance
B)lapse in aseptic techniques
C)gram-negative cell walls
D)lack of handwashing
E)lack of disinfecting surfaces

Question 14

Which of the following is NOT a communicable disease?

A)malaria
B)AIDS
C)tuberculosis
D)tetanus
E)typhoid fever

Question 15

Biological transmission differs from mechanical transmission in that biological transmission

A)occurs when a pathogen is carried on the feet of an insect.
B)involves fomites.
C)involves reproduction of a pathogen in an arthropod vector prior to transmission.
D)requires direct contact.
E)works only with noncommunicable diseases.

Question 16

Which of the following definitions is INCORRECT?

A)acute: a short-lasting primary infection
B)inapparent: infection characteristic of a carrier state
C)chronic: a disease that develops slowly and lasts for months
D)primary infection: an initial illness
E)secondary infection: a long-lasting illness

Question 17

Which of the following statements about biological transmission is FALSE?

A)The pathogen reproduces in the vector.
B)The pathogen may enter the host in the vector's feces.
C)Houseflies are an important vector.
D)The pathogen may be injected by the bite of the vector.
E)The pathogen may require the vector as a host.

Question 18

One effect of washing regularly with antibacterial agents is the removal of normal microbiota.This can result in

A)body odor.
B)fewer diseases.
C)increased susceptibility to disease.
D)normal microbiota returning immediately.
E)no bacterial growth because washing removes their food source.

Question 19

Which of the following is NOT a verified exception in the use of Koch's postulates?

A)Some diseases have poorly defined etiologies.
B)Some pathogens can cause several disease conditions.
C)Some human diseases have no other known animal host.
D)Some diseases are not caused by microbes.
E)Some diseases are noncommunicable.

Question 20

The rise in herd immunity amongst a population can be directly attributed to

A)increased use of antibiotics.
B)improved handwashing.
C)vaccinations.
D)antibiotic-resistant microorganisms.
E)None of the answers is correct.

Question 21

A researcher has performed a prospective study on a disease.To which specific kind of epidemiological study is this referring?

A)analytical
B)case control
C)descriptive
D)experimental
E)prodromal

Question 22

In which of the following diseases can gender be considered a viable predisposing factor?

A)urinary tract infections
B)pneumonia
C)salmonellosis
D)tetanus
E)anthrax

Question 23

Refer to figure 14.1

In Figure 14.1,which letter indicates the gradual end of the epidemic outbreak?

A)a
B)b
C)c
D)d

Question 24

Which of the following can contribute to postoperative infections?

A)using syringes more than once
B)normal microbiota on the operating room staff
C)errors in aseptic technique
D)antibiotic resistance
E)All of the answers are correct.

Question 25

Which of the following is NOT a predisposing factor of disease?

A)lifestyle
B)genetic background
C)climate
D)occupation
E)All of these are predisposing factors of disease.

Question 26

Refer to figure 14.1

In Figure 14.1,which letter on the graph indicates the epidemic level?

A)a
B)b
C)c
D)d

Question 27

Which of the following pairs is mismatched?

A)malaria - foodborne transmission
B)salmonellosis - vehicle transmission
C)syphilis - direct contact
D)influenza - droplet infection

Question 28

Symptoms of disease differ from signs of disease in that symptoms

A)are changes felt by the patient.
B)are changes observed by the physician.
C)are specific for a particular disease.
D)always occur as part of a syndrome.

Question 29

Refer to Figure 14.2

In Figure 14.2,when is the prevalence the highest?

A)July
B)January
C)February
D)March

Question 30

A disease in which the causative agent remains inactive for a time before producing symptoms is referred to as

A)subacute.
B)subclinical.
C)latent.
D)zoonotic.
E)acute.

Question 31

Would you expect the graph to change if this was for the southern hemisphere,rather than the northern hemisphere? If so,how?

A)No,the graph would not change.Influenza epidemics occur at the same time each year.
B)Yes,because the population in the northern hemisphere is less than that in the southern hemisphere,the peak of the graph would be higher.
C)Yes,because the weather is hotter in the southern hemisphere than in the northern hemisphere,you could expect to see less cases overall in the graph,leading to a lower peak.
D)Yes,because the seasons are reversed in the southern hemisphere.While weather doesn't directly cause influenza outbreaks,the cold,dry air and human crowding indoors contribute to increased cases.The southern hemisphere would still have a peak,but it would be at a different time of year than the northern hemisphere.

Question 32

The CDC is located in

A)Atlanta,GA.
B)Washington,DC.
C)New York City,NY.
D)Los Angeles,CA.
E)Chicago,IL.

Question 33

The science that deals with when diseases occur and how they are transmitted is called

A)ecology.
B)epidemiology.
C)communicable disease.
D)morbidity and mortality.
E)public health.

Question 34

Situation 14.1 is an example of

A)human reservoirs.
B)a zoonosis.
C)a nonliving reservoir.
D)a vector.
E)a focal infection.

Question 35

Refer to figure 14.1

Figure 14.1 shows the incidence of influenza during a typical year in the northern hemisphere.Which letter on the graph indicates the endemic level?

A)a
B)b
C)c
D)d

Question 36

Emergence of infectious diseases can be attributed to all of the following EXCEPT

A)antibiotic resistance.
B)climatic changes.
C)new strains of previously known agents.
D)ease of travel.
E)The emergence of infectious diseases can be attributed to all of these.

Question 37

Refer to Figure 14.2

In Figure 14.2,which one of the following choices has the highest morbidity rate?

A)July
B)October
C)November
D)December

Question 38

A needlestick is an example of

A)direct contact.
B)droplet transmission.
C)indirect contact transmission by fomite.
D)direct biological transmission by vector.
E)vehicle transmission.

Question 39

In which of the following patterns of disease does the patient experience no signs or symptoms?

A)prodromal
B)decline
C)convalescence
D)incubation
E)both incubation and convalescence

Question 40

A cold transmitted by a facial tissue is an example of

A)direct contact.
B)droplet transmission.
C)fomite.
D)vector.
E)vehicle transmission.

Question 41

Pseudomonas bacteria colonized the bile duct of a patient following his liver transplant surgery.This is an example of a

A)communicable disease.
B)latent infection.
C)nosocomial infection.
D)sporadic disease.
E)None of the answers is correct.

Question 42

MMWR is a publication by the CDC that reports specifically and only on emerging diseases.

Question 43

The yeast Candida albicans does NOT normally cause disease because of

A)symbiotic bacteria.
B)antagonistic bacteria.
C)parasitic bacteria.
D)commensal bacteria.
E)other fungi.

Question 44

Refer to Figure 14.3 for the next several questions.

The graph in Figure 14.3 shows the incidence of polio in the United States.The period between 1945 and 1955 indicates a(n)

A)endemic level.
B)epidemic level.
C)sporadic infection.
D)communicable disease.
E)pandemic.

Question 45

Interpreting this graph,can we conclude that polio has been eradicated globally? Why or why not?

A)Yes,as the number of reported cases goes to zero around 1965.
B)No,because polio is part of the normal microbiota,and could become resurgent if vaccination efforts lapse.
C)No,because the graph only depicts incidence of polio in the United States.
D)Yes,because a zero incidence rate for over 40 years clearly indicates there are no longer any susceptibles left in the global population.

Question 46

If a prodromal period exists for a certain disease,it should occur prior to

A)incubation.
B)illness.
C)decline.
D)convalescence.

Question 47

Which of the following statements is FALSE?

A)Antimicrobial therapy for hemodialysis-associated infections increases antibiotic resistance.
B)S)aureus is differentiated from other mannitol+ cocci by the coagulase test.
C)The M in MRSA stands for mannitol.
D)The USA100 strain accounts for most hospital-acquired MRSA.
E)The USA300 strain accounts for most community-acquired MRSA.

Question 48

Bloodstream infections are the least common forms of nosocomial infections.

Question 49

Which of the following is NOT an example of microbial antagonism?

A)acid production by bacteria
B)bacteriocin production
C)bacteria occupying host receptors
D)bacteria causing disease
E)bacteria producing vitamin K

Question 50

The method of transmission of the disease in Situation 14.1 was

A)direct contact.
B)droplet.
C)indirect contact.
D)vector-borne.
E)vehicle.

Question 51

A burn patient is one example of a compromised host.

Question 52

Testing the effectiveness of a new drug for anthrax would be best performed as an experimental study.

Question 53

The etiologic agent of the disease in Situation 14.1 is

A)sheep.
B)soil.
C)Coxiella burnetii.
D)pneumonia.
E)wind.

Question 54

Diseases that are referred to as emerging infectious diseases have only been discovered in the past fifty years.

Question 55

A researcher only needs to select a cohort group when implementing an analytical epidemiological study.

Question 56

Which one of the following is NOT a zoonosis?

A)cat-scratch disease
B)Hantavirus pulmonary syndrome
C)rabies
D)tapeworm
E)All of these are zoonoses.

Question 57

A host is not considered diseased until an infection changes one's state of health.

Question 58

Both normal and transient flora can become opportunistic pathogens.

Question 59

Reservoirs of infections are always inanimate objects.

Question 60

For a particular disease at a specific time period,morbidity rates should always be equal or greater than mortality rates.

Question 61

Situation 14.2
A 37-week-old infant was delivered by cesarean section and discharged from a Connecticut hospital when he was ten days old.Two days later he was lethargic and had a fever.When he was readmitted to the hospital,he had multiple brain abscesses caused by Citrobacter diversus.After a prolonged illness,the baby died.A second infant with a normal pregnancy and delivery died of C.diversus meningitis after a short illness.Nine infants in the hospital nursery had umbilical cord colonization by C.diversus.Environmental cultures were negative for hospital equipment.
Refer to Situation 14.2 What is the normal habitat of this gram-negative,facultatively anaerobic,non-endospore-forming,lactose-positive rod? Provide a plan for identifying the source of infection and preventing further infection.

Question 62

Would you expect all EIDs to be on the notifiable infectious disease list? Explain.

Question 63

When studying the epidemiology of a particular disease,why are retrospective studies commonly undertaken before prospective studies?

Question 64

Zika virus infection,a zoonotic disease,produced somewhat sizable outbreaks recently in certain areas of Central America,but not in the U.S (although there were some infected individuals uncovered in the U.S.).Provide two plausible explanations for this dichotomy,and explain.

Question 65

Figure 14.4

Salmonella Heidelberg gastroenteritis occurred on three cruises aboard the T.S.S.Festivale.Figure 14.4 shows on-board clinic visits for diarrheal illness between February 10 and March 3.Explain the incidence pattern shown on the graph.What are probable modes of transmission? What changes would you recommend before the ship books more cruises after March 3?