Exam
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1)
Which of the following is NOT a communicable diseases?
1)
A)
typhoid fever
B)
malaria
C)
tetanus
D)
tuberculosis
E)
AIDS
2)
The major significance of Robert Koch’s work is that
2)
A)
microorganisms can be cultured.
B)
microorganisms are present in a diseased animal.
C)
microorganisms are the result of disease.
D)
diseases can be transmitted from one animal to another.
E)
microorganisms cause disease.
3)
Koch observed Bacillus anthracis multiplying in the blood of cattle. What is this condition called?
3)
A)
local infection
B)
systemic infection
C)
bacteremia
D)
septicemia
E)
focal infection
4)
Pseudomonas bacteria colonized the bile duct of a patient following his liver transplant surgery. This
is an example of a
4)
A)
latent infection.
B)
communicable disease.
C)
nosocomial infection.
D)
sporadic disease.
E)
None of the answers is correct.
5)
A commensal bacterium
5)
A)
may also be an opportunistic pathogen.
B)
is beneficial to its host.
C)
does not receive any benefit from its host.
D)
does not infect its host.
E)
is beneficial to, and does not infect, its host.
6)
Which of the following statements is FALSE?
6)
A)
The USA300 strain accounts for most community–acquired MRSA.
B)
Antimicrobial therapy for hemodialysis–associated infections increases antibiotic resistance.
C)
The M in MRSA stands for mannitol.
D)
The USA100 strain accounts for most hospital–acquired MRSA.
E)
S. aureus is differentiated from other mannitol+ cocci by the coagulase test.
7)
The yeast Candida albicans does not normally cause disease because of
7)
A)
symbiotic bacteria.
B)
antagonistic bacteria.
C)
other fungi.
D)
commensal bacteria.
E)
parasitic bacteria.
8)
Which of the following diseases is NOT spread by droplet infection?
8)
A)
the common cold
B)
measles
C)
tuberculosis
D)
botulism
E)
diphtheria
9)
Which of the following statements about biological transmission is FALSE?
9)
A)
The pathogen may require the vector as a host.
B)
The pathogen may be injected by the bite of the vector.
C)
The pathogen reproduces in the vector.
D)
The pathogen may enter the host in the vector’s feces.
E)
Houseflies are an important vector.
10)
A researcher has performed a prospective study on the disease tetanus. To which specific kind of
epidemiological study is this referring?
10)
A)
case control
B)
descriptive
C)
prodromal
D)
experimental
E)
analytical
11)
Symptoms of disease differ from signs of disease in that symptoms
11)
A)
are specific for a particular disease.
B)
are changes observed by the physician.
C)
are changes felt by the patient.
D)
always occur as part of a syndrome.
E)
None of the answers is correct.
12)
Which of the following statements is TRUE?
12)
A)
Symbiosis refers to different organisms living together and benefiting from each other.
B)
Members of a symbiotic relationship cannot live without each other.
C)
At least one member must benefit in a symbiotic relationship.
D)
At least one member must not benefit in a symbiotic relationship.
E)
A parasite is not in symbiosis with its host.
13)
If a prodromal period exists for a certain disease, it should occur prior to
13)
A)
convalescence.
B)
illness.
C)
incubation.
D)
decline.
14)
Which of the following is a fomite?
14)
A)
a hypodermic needle
B)
insects
C)
water
D)
droplets from a sneeze
E)
pus
15)
Which of the following can contribute to postoperative infections?
15)
A)
using syringes more than once
B)
errors in aseptic technique
C)
antibiotic resistance
D)
normal microbiota on the operating room staff
E)
All of the answers are correct.
16)
The CDC is located in
16)
A)
Washington, DC.
B)
New York City, NY.
C)
Chicago, IL.
D)
Las Angeles, CA.
E)
Atlanta, GA.
17)
A cold transmitted by a facial tissue is an example of
17)
A)
droplet transmission.
B)
vehicle transmission.
C)
direct contact.
D)
vector.
E)
fomite.
18)
Which of the following is NOT an example of microbial antagonism?
18)
A)
bacteria producing vitamin K
B)
bacteriocin production
C)
bacteria occupying host receptors
D)
bacteria causing disease
E)
acid production by bacteria
Situation 14.1
During a six–month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever
39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints,
fatigue, or feeling ill). A laboratory–confirmed case was defined as a positive result for antibodies against Coxiella burnetii.
Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for
C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the
previous three years.
19)
The method of transmission of the disease in Situation 14.1 was
19)
A)
droplet.
B)
direct contact.
C)
vector–borne.
D)
indirect contact.
E)
vehicle.
20)
Which of the following is NOT a verified exception in the use of Koch’s postulates?
20)
A)
Some pathogens can cause several disease conditions.
B)
Some human diseases have no other known animal host.
C)
Some diseases are not caused by microbes.
D)
Some diseases are noncommunicable.
E)
Some diseases have poorly defined etiologies.
21)
A needlestick is an example of
21)
A)
droplet transmission.
B)
vector.
C)
fomite.
D)
vehicle transmission.
E)
direct contact.
22)
Emergence of infectious diseases can be attributed to all of the following EXCEPT
22)
A)
new strains of previously known agents.
B)
antibiotic resistance.
C)
ease of travel.
D)
climatic changes.
E)
None of the answers is correct; the emergence of infectious diseases can be attributed to all of
these.
23)
Which of the following is NOT a predisposing factor of disease?
23)
A)
occupation
B)
climate
C)
genetic background
D)
lifestyle
E)
None of the answers are correct; all of these are predisposing factors of disease.
24)
Which of the following is NOT a reservoir of infection?
24)
A)
a hospital
B)
a sick person
C)
a healthy person
D)
a sick animal
E)
None of the answers is correct; all of these can be reservoirs of infection.
25)
In which of the following diseases can gender be considered a viable predisposing factor?
25)
A)
salmonellosis
B)
pneumonia
C)
urinary tract infections
D)
anthrax
E)
tetanus
26)
In Figure 14.2, when is the prevalence the highest?
26)
A)
February
B)
March
C)
July
D)
January
E)
The answer cannot be determined based on the information provided.
A
27)
Which one of the following is NOT a zoonosis?
27)
A)
tapeworm
B)
cat–scratch disease
C)
rabies
D)
Hantavirus pulmonary syndrome
E)
None of the answers is correct; all of these are zoonoses.
E
28)
Biological transmission differs from mechanical transmission in that biological transmission
28)
A)
requires an arthropod.
B)
requires direct contact.
C)
works only with noncommunicable diseases.
D)
involves specific diseases.
E)
involves fomites.
29)
Focal infections initially start out as
29)
A)
septicemia.
B)
systemic infections.
C)
bacteremia.
D)
sepsis.
E)
local infections.
Situation 14.1
During a six–month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever
39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints,
fatigue, or feeling ill). A laboratory–confirmed case was defined as a positive result for antibodies against Coxiella burnetii.
Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for
C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the
previous three years.
30)
Situation 14.1 is an example of
30)
A)
a zoonosis.
B)
a focal infection.
C)
a nonliving reservoir.
D)
a vector.
E)
human reservoirs.
31)
The rise in herd immunity amongst a population can directly attributed to
31)
A)
antibiotic–resistant microorganisms.
B)
improved handwashing.
C)
vaccinations.
D)
increased use of antibiotics.
E)
None of the answers is correct.
32)
Which of the following statements about nosocomial infections is FALSE?
32)
A)
They may be caused by normal microbiota.
B)
They may be caused by drug–resistant bacteria.
C)
They may be caused by opportunists.
D)
The patient was infected before hospitalization.
E)
They occur in compromised patients.
33)
Transient microbiota differ from normal microbiota in that transient microbiota
33)
A)
are always acquired by direct contact.
B)
never cause disease.
C)
are present for a relatively short time.
D)
cause diseases.
E)
are found in a certain location on the host.
Figure 14.1
34)
Figure 14.1 shows the incidence of influenza during a typical year. Which letter on the graph
indicates the endemic level?
34)
A)
a
B)
b
C)
c
D)
d
E)
The answer cannot be determined based on the information provided.
35)
The science that deals with when diseases occur and how they are transmitted is called
35)
A)
communicable disease.
B)
morbidity and mortality.
C)
public health.
D)
ecology.
E)
epidemiology.
E
D
36)
One effect of washing regularly with antibacterial agents is the removal of normal microbiota. This
can result in
36)
A)
fewer diseases.
B)
no bacterial growth because washing removes their food source.
C)
normal microbiota returning immediately.
D)
body odor.
E)
increased susceptibility to disease.
37)
Which of the following definitions is INCORRECT?
37)
A)
primary infection: an initial illness
B)
chronic: a disease that develops slowly and lasts for months
C)
inapparent: infection characteristic of a carrier state
D)
secondary infection: a long–lasting illness
E)
acute: a short–lasting primary infection
38)
In which of the following patterns of disease does the patient experience no signs or symptoms?
38)
A)
decline
B)
prodromal
C)
convalescence
D)
incubation
E)
incubation and convalescence
Explanation:
39)
A disease in which the causative agent remains inactive for a time before producing symptoms is
referred to as
39)
A)
zoonotic.
B)
latent.
C)
subacute.
D)
subclinical.
E)
acute.
40)
Which one of the following does NOT contribute to the incidence of nosocomial infections?
40)
A)
gram–negative cell walls
B)
antibiotic resistance
C)
lack of handwashing
D)
lapse in aseptic techniques
E)
lack of insect control
Figure 14.3
41)
The graph in Figure 14.3 shows the incidence of polio in the United States. The period between
1945 and 1955 indicates a(n)
41)
A)
endemic level.
B)
sporadic infection.
C)
pandemic.
D)
communicable disease.
E)
epidemic level.
42)
Which of the following definitions is INCORRECT?
42)
A)
epidemic: a disease that is endemic across the world
B)
endemic: a disease that is constantly present in a population
C)
incidence: number of new cases of a disease
D)
pandemic: a disease that affects a large number of people in the world in a short time
E)
sporadic: a disease that affects a population occasionally
43)
Which of the following pairs is mismatched?
43)
A)
influenza droplet infection
B)
malaria vector
C)
salmonellosis vehicle transmission
D)
syphilis direct contact
E)
None of the pairs is mismatched.
44)
A nosocomial infection is
44)
A)
only a result of surgery.
B)
always caused by medical personnel.
C)
always present, but is inapparent at the time of hospitalization.
D)
always caused by pathogenic bacteria.
E)
acquired during the course of hospitalization.
Situation 14.1
During a six–month period, 239 cases of pneumonia occurred in a town of 300 people. A clinical case was defined as fever
39°C lasting >2 days with three or more symptoms (i.e., chills, sweats, severe headache, cough, aching muscles/joints,
fatigue, or feeling ill). A laboratory–confirmed case was defined as a positive result for antibodies against Coxiella burnetii.
Before the outbreak, 2000 sheep were kept northwest of the town. Of the 20 sheep tested from the flock, 15 were positive for
C. burnetii antibodies. Wind blew from the northwest, and rainfall was 0.5 cm compared with 7 to 10 cm during each of the
previous three years.
45)
The etiologic agent of the disease in Situation 14.1 is
45)
A)
soil.
B)
wind.
C)
sheep.
D)
pneumonia.
E)
Coxiella burnetii.
TRUE/FALSE. Write ‘T’ if the statement is true and ‘F’ if the statement is false.
46)
A host is not considered diseased until an infection changes one’s state of health.
46)
47)
Urinary tract infections are the most common forms of nosocomial infections.
47)
48)
MMWR is a publication by the CDC that reports on only emerging diseases.
48)
49)
Diseases that are referred to as EIDs have only been discovered in the past fifty years.
49)
50)
Reservoirs of infections are always animate objects.
50)
51)
A researcher only needs to select a cohort group when implementing an analytical epidemiological
study.
51)
52)
Both normal and transient flora can become opportunistic pathogens.
52)
53)
Compromised hosts are always suffering from suppressed immune systems.
53)
54)
For a particular disease at a specific time period, morbidity rates should always be equal or greater
than mortality rates.
54)
55)
Testing the effectiveness of a new drug for anthrax would be best performed as an experimental
study.
55)
ESSAY. Write your answer in the space provided or on a separate sheet of paper.
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.
56)
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.
57)
Dengue fever, a zoonotic disease, is endemic in northern Mexico, but not in the U.S. Provide two plausible
explanations for this dichotomy, and explain.
58)
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?
59)
When studying the epidemiology of a particular disease, why are retrospective studies commonly undertaken
before prospective studies?
60)
Would you expect all EIDs to be on the notifiable infectious disease list? Explain.
Answer Key
Testname: C14
18
Answer Key
Testname: C14