Final Exam KEY, Epidemiology 227
June 9, 2003
Select the best answer for the multiple choice questions. There are 75 questions and 13 pages on
the examination. Each question will count one point. Notify the instructor if your examination
does not have 9 pages. Clearly indicate on the scan form the one best answer to each question
among the answers provided. Be sure that you have selected your choice correctly on the scan
form. Be sure that you have entered your name and identification number on the scan form and
filled out the columns for the letters of your name and numbers of your identification number
correctly (see front and back). Use a #2 pencil and fill all circles completely.
1.
What is the cost per confirmed HIV infection of testing for HIV in a population of one
million persons if the sensitivity of the Elisa test is 99.8% and the specificity is 99.9%,
and the sensitivity of the Western blot test is 99.8%? The unit cost of counseling plus the
Elisa test is $60, and the unit cost of the Western blot is $120. The total cost of the Elisa
test and counseling for the one million persons is $60,000,000, and for the Western blot
test of the Elisa test positives is $1,317,600. Nine hundred and eighty eight (988)
persons were confirmed to be HIV-infected:
a.
60,000,000 + 1,317,000  988 = $62,062
b.
60,000,000 - 1,317,000  988 = $59,396
c.
60,000,00 x .998 + 1,317,000 x .999  988 = $61,939
d.
60,000,000 + 1,317,000  1,000,000 = $61
e.
Predictive value positive - predictive value negative x $60 x $120
2.
Individuals who test positive at home using the rapid test for HIV should first:
a.
Immediately start HAART treatment
b.
Initiate treatment first with nevirapine
c.
Get a confirmatory test
d.
Notify their sexual partners
e.
Write a will
3.
If all persons in the United States were tested for HIV using an Elisa test with a
sensitivity of 99.8% and a specificity of 99.9%, there would be:
a.
More false positives than true positives
b.
More true positives than false positives
c.
More false negatives than true negatives
d.
More false negatives than false positives
1
4.
Which of the following was NOT a social impact of the HIV epidemic on the Agay@
community?
a.
Men initially decreased the number of different sexual partners
b.
Men started practicing Asafer sex@
c.
There was an increase in the number of Agay@ support groups
d.
Most men switched to having sex with women
e.
There was an emergence of Agay families@
5.
AAIDS fatigue@ refers to:
a.
The exhaustion that accompanies having a diagnosis of AIDS
b.
Gay men are tired of talking about the AIDS epidemic and AIDS
c.
The upsurge of risky behavior among men under 20 who are gay
d.
The heterosexual population is becoming tired of talking about HIV in the gay
community
e.
None of the above
6.
Men of color are at increased risk of becoming HIV-infected because of their fear of
homophobia in their communities:
a.
True
b.
False
7.
What is the proportion of HIV Ag+ positive donors who are HIV Ab-?
a.
1 per 100,000
b.
1 per 500,000
c.
1 per million
d.
1 per 4 million
e.
1 per 9 million
8.
If a blood donor=s blood is found to be HIV-positive, s/he will be so informed:
a.
True
b.
False
9.
The three guiding principles of ethical research involving humans are:
a.
Empathy, caution and truthfulness
b.
Respect for persons, beneficence and justice
c.
Respect for human dignity, compensation and integrity
d.
Beneficence, legal recourse and reimbursement
e.
Legal recourse, justice and compensation
2
10.
The most important component of human subjects protection is:
a.
Compensation
b.
Informed consent
c.
Taking only 10cc=s of blood
d.
Not asking personally embarrassing questions
e.
Providing the telephone number of the principal investigator
11.
The primary goal of public health is to:
a.
Protect infected individuals
b.
Protect uninfected individuals
c.
Inform the spouses of infected individuals
d.
Determine the mortality rate of all infectious diseases
12.
Informed consent includes which of the following?
a.
Purpose of study
b.
Description of study
c.
Description of foreseeable risks and discomforts
d.
Reasonably expected benefits
e.
All of the above
13.
Which of the following is NOT considered to be a risk of human research?
a.
Physical harm
b.
Social harm
c.
Psychological harm
d.
Inadequate compensation
e.
Economic harm
14.
As part of ethical research, a potential human subject must:
a.
Be provided alternative sources of medical care, which is part of the research
project
b.
Be informed of alternative sources of medical care, which is part of the
research project
c.
Be denied alternative sources of care
15.
Guaranteeing anonymity means that the researcher will:
a.
Keep identifying information safeguarded and disclose it to no one without the
permission of the research participant
b.
Will not collect identifying information
c.
Will not inform the participant that s/he is collecting identifying information
d.
Will only release identifying information if required to by a judge
3
16.
The success of individual level interventions depends on:
a.
Reaching the riskiest individuals
b.
Reaching enough of the riskiest individuals
c.
Having an intervention that is sufficiently intensive
d.
All of the above
e.
a. and c. above
17.
The proportion of AIDS cases associated with injection drug use is higher among men
than among women in the U.S.:
a.
True
b.
False
18.
Party drugs such as ASpecial K@, GHB, Poppers and Ecstasy:
a.
Are associated with injection drug use
b.
Are associated with increased sexual transmission risk
c.
Are equally associated with both
d.
Are associated with neither
19.
In the U.S., crystal methamphetamine is most popular among:
a.
Whites
b.
African-Americans
c.
Latinos
d.
Asians
e.
Used equally by all of the above groups
20.
In the U.S., which of the following drugs is most often associated with increased
unprotected sexual intercourse among men-who-have-sex-with-men?
a.
Heroin
b.
Cocaine
c.
Methamphetamine
d.
G-MA
e.
ASpeed ball@ (dual)
21.
Needle exchange programs have NOT been shown to reduce HIV prevalence:
a.
True
b.
False
22.
Methadone maintenance is associated with decreased injection and sex-related risk
behaviors in most studies:
a.
True
b.
False
4
23.
Injection drug users in many parts of Asia are easier to target for prevention and
intervention because:
a.
They usually remain part of their family
b.
They usually remain part of their community
c.
They tend to congregate in urban areas in countries like China
d.
All of the above
e.
a. and b. above
24.
Drug rehabilitation centers are a cost-effective strategy for controlling drug addiction
among young men in Asia:
a.
True
b.
False
25.
Successful community mobilization/intervention programs in rural areas depend on:
a.
Unlimited funding and health personnel from the government
b.
Acceptance of responsibility by the local community
c.
Acceptance of the problem by the local community
d.
All of the above
e.
b. and c. above
26.
The major key to the success of the Multicenter AIDS Cohort Study (MACS) has been:
a.
The skill of the principal investigator
b.
The qualifications of the staff
c.
The significant amount of funding from the National Institutes of Health
d.
The commitment of the participants
e.
The sexual orientation of the staff
27.
Which of the following groups identified in the MACS is likely to provide key
information for development of a vaccine to prevent HIV infection?
a.
Long-term non-progressors
b.
High-risk seronegatives
c.
Low-risk seronegatives
d.
Long-term survivors with less than 50 CD4 cells
e.
Rapid progressors
28.
The most effective health education/behavioral intervention strategies use:
a.
The Aempty vessel@ strategy
b.
As many different strategies as possible
c.
Provide only the important information on HIV
d.
Target only high-risk individuals
e.
A combination of effective strategies
5
29.
The diffusion of innovation strategy suggests targeting first the:
a.
Early innovators
b.
Middle innovators
c.
Late adopters
d.
The laggards
e.
All of the above
30.
Which is NOT one of the stages of behavior change?
a.
Precontemplation
b.
Preparation
c.
Maintenance
d.
Reconsideration
e.
Contemplation
31.
With the use of highly active antiretroviral therapy given to the mother beginning in the
second trimester of pregnancy and to the infant for one week after birth, the risk of
transmission from mother to child can be reduced to:
a.
Less than 20%
b.
Less than 10%
c.
Less than 5%
d.
Less than 2%
e.
0%
32.
The highest risk of transmission from mother to infant occurs:
a.
In-utero
b.
During the birth process
c.
Through breast feeding
d.
The risk is equal during all stages of pregnancy and delivery
33.
Factors which increase the risk of transmission from mother to infant include:
a.
The phenotype of the virus
b.
The stage of HIV disease in the mother
c.
The level of HIV in the mother
d.
All of the above
e.
b. and c. above
34.
Mixing/alternating breast feeding with formula feeding reduces the risk of HIV infection:
a.
True
b.
False
6
35.
Delivering the baby by C-section is recommended for mothers who are on highly active
antiretroviral therapy:
a.
True
b.
False
36.
Protease inhibitors do not reduce the risk of HIV transmission in infants because they do
not cross the placental barrier:
a.
True
b.
False
37.
The rate of HIV disease progression is highest in babies who were infected:
a.
In-utereo
b.
During the birth process
c.
During breast feeding
d.
The rate of progression is the same in all three of the above
38.
A slower rate of progression of HIV disease in the baby is associated with:
a.
The presence of high levels of neutralizing antibody in the mother
b.
The presence of high levels of neutralizing antibody in the baby
c.
Early appearance of HIV diversity in the baby
d.
All of the above
e.
b. and c. above
39.
The most important step in effective national control of HIV/AIDS is:
a.
Mobilization of political will and commitment
b.
Focused interventions to marginalized groups
c.
Reduction of stigmatization
d.
Identification of risk groups
e.
Suppression of risk groups
40.
The objectives of an HIV vaccine program may include:
a.
Prevention of infection
b.
Prevention of disease
c.
Prevention of transmission
d.
All of the above
e.
a. and c. above
41.
The major barrier to the development of an HIV vaccine has been:
a.
The cost of developing the drug
b.
The lack of demonstrated natural immunity following HIV infection
c.
The presence of two types of HIV: CD4-tropic and macrophage-tropic
d.
The lack of political commitment for the development of a vaccine
e.
Concerns about the safety of the vaccine
7
42.
The following are requirements for an effective HIV vaccine EXCEPT:
a.
Must be safe
b.
Must elicit a protective response
c.
Must stimulate a cytotoxic lymphocyte response
d.
Must stimulate IgM antibodies
e.
Must be practical to produce, transport and administer
43.
Current risk of getting infected with HIV through blood transfusion in the United States
is:
a.
1 per 1, 800,000
b.
1 per 1, 600,000
c.
1 per 9,000,000
d.
1 per 63,000
44.
Which one of these is NOT a layer of safety implement in blood safety in the United
States?
a.
Self exclusion in response to written material
b.
Health history interview
c.
Laboratory testing
d.
Viral inactivation
e.
Partner notification
45.
The pool nucleic acid technology (NAT) testing used in the American Red Cross will
eliminate what proportion of the remaining viremic window?
a.
10%-20%
b.
30%-50%
c.
60%-80%
d.
100%
46.
Partner Counseling and Referral Services in LA County provide a range of services
but do NOT provide follow-up service to:
a.
HIV+ clients
b.
HIV- clients
c.
Sexual partners of HIV+ clients
d.
Needle-sharing partners of HIV+ clients
47.
It is appropriate to exclude non-English speaking subjects if it is too costly to
translate the consent document:
a.
True
b.
False
8
48.
Minimal risk is defined as one of the following:
a.
The risk of an additional procedure performed solely for research purposes,
such as an additional CT scan
b.
The risk encountered in daily life during the performance of routine
physical or psychological examinations or test
c.
A procedure that may result in a little harm relative to the standard
procedures
d.
The low probability that a subject will feel sick after participating
49.
Increasing knowledge about HIV/AIDS is:
a.
Sufficient but not necessary
b.
Necessary but not sufficient
c.
Sufficient and necessary
50.
One of several factors that may be attributed to the resurgence of the HIV epidemic
among men who have sex with men in the United States is:
a.
Discrimination against men who have sex with men
b.
Changes in beliefs regarding the severity of HIV disease
c.
There are few intervention programs for men who have sex with men
51.
Recent CDC HIV testing guidelines state that all pregnant women in the United
States must be tested for HIV as a routine part of prenatal care:
a.
True
b.
False
52.
The risks of implementing early therapy in asymptomatic HIV-infected patients
include all those listed below EXCEPT:
a.
Drug-related reduction in quality of life
b.
Earlier development of drug resistance if viral suppression is suboptimal
c.
Limitation of future antiretroviral treatment options
d.
Possible decreased risk of HIV transmission
53.
The inability of mature T cells and B cells to pathologically respond to self is known
as:
a.
Tolerance
b.
Central tolerance
c.
Peripheral tolerance
d.
Autoimmune
54.
The two known types of HIV (HIV-1 and HIV-2) belong to a family of:
a.
Lentiviruses
b.
Oncoviruses
c.
Spumaviruses
9
55.
Infants infected in-utero tend to experience slow progression, whereas those
infected during the birth process or infected through breast milk tend to experience
a faster course:
a.
True
b.
False
56.
The type of first antiretroviral drug to show an effect in humans was:
a.
Reverse transcriptase inhibitors
b.
Protease inhibitors
c.
Integrase inhibitors
d.
gp120 blockers
e.
A combination of the three above
57.
The major AIDS-defining illness in most developing countries is:
a.
Pneumocystis carinii
b.
Kaposis sarcoma
c.
Lymphoma
d.
Tuberculosis
58.
The rate of new HIV infections is probably declining in which one of the following
Asian countries:
a.
China
b.
India
c.
Vietnam
d.
Myamar
e.
Cambodia
59.
The major mode of spread of HIV in the world is through:
a.
Homosexual activities
b.
Needle sharing among injecting drug users
c.
Heterosexual activities
d.
Unscreened blood
e.
Infected mother to infant
60.
The set point refers to:
a.
The level of CD4 cells after the initial stage of HIV infection
b.
The level of CD8 cells after the initial stage of HIV infection
c.
The level of viral load after the initial stage of HIV infection
d.
The level of viral load at the late stage of HIV infection
10
61.
HIV infection alone can cause all of the following EXCEPT:
a.
AIDS dementia
b.
Direct killing of neurons
c.
Vacuolar myelopathy
d.
Peripheral neuropathy
e.
Meningitis
62.
In 2002, worldwide, the number of adults and children NEWLY infected with HIV is:
a.
2 million
b.
3 million
c.
4 million
d.
5 million
63.
In 2002, worldwide, what percentage of new HIV infections occured in developing
countries?
a.
Almost 50%
b.
More than 95%
c.
Less than 50%
d.
About 75%
64.
During 2002, the highest number of HIV/AIDS cases occurred in which area?
a.
Sub-Saharan Africa
b.
Southeast Asia
c.
China
d.
Russia and the former Soviet Union
e.
United States
65.
The highest proportion of HIV-infected persons in the United States were in which risk
group?
a.
Men-who-have-sex-with-men
b.
Heterosexuals
c.
Injection drug users
d.
Plasma donors
e.
Hemophiliacs
66.
The risk group with the greatest rate of decline in the proportion of AIDS cases in the
United States has been:
a.
Men-who-have-sex-with-men
b.
Heterosexuals
c.
Injection drug users
d.
Plasma donors
e.
Hemophiliacs
11
67.
The advantages of using the saliva test include all of the following EXCEPT:
a.
It is non-invasive
b.
It is more acceptable to most people than giving a blood specimen
c.
As many as five specimens can be pooled for testing
d.
It is not necessary to keep the specimens cold during transport
e.
It does not require sterile needles and syringes
68.
ARisk-free Testing@ refers to:
a.
Collecting blood for testing without risk of HIV infection occurring
b.
Testing without the risk of disclosure of testing or test results
c.
Testing without the risk of hematomas occurring at the site of the blood collection
d.
Using urine for testing
e.
Using saliva for testing
69.
DNA polymerase converts:
a.
CCR-5-tropic HIV to CRCX-4-tropic HIV
b.
Gag to pol
c.
Env to pol
d.
RNA to DNA
e.
DNA to RNA
70.
Immune deficiency causing an inability of the immune cells to respond to infection occurs
immediately after HIV infection of the individual:
a.
True
b.
False
71.
Which component of the HIV virion first attaches to the CD4 cell?
a.
P24
b.
GP41
c.
GP120
d.
The lipid envelope
e.
Pol proteins
72.
The major characteristics of adaptive immunity are all of the following EXCEPT:
a.
Antigen specificity
b.
Diversity
c.
Memory
d.
Self/non-self recognition
e.
Immediate protection
12
73.
The most effective cell of the immune system response to HIV is which of the following?
a.
CD4 cells
b.
CD8 cells
c.
B cells
d.
NK cells
e.
Plasma cells
74.
The key characteristic of an effective HAART regimen is to include:
a.
One drug from each of the three classes of drugs
b.
Three drugs, with one drug from at least two of the three classes of drugs
c.
One protease inhibitor
d.
Zidovudine
e.
Four drugs, with at least one drug from all three classes of drugs
75.
A major objective of surveillance is to stimulate political and social action:
a.
True
b.
False
13