1
ACVPM Practice Test Actual Exam
2026/2027 – Complete Exam-Style Questions
with Detailed Rationales | 100% Verified |
Pass Guaranteed – A+ Graded
[SECTION 1: Epidemiology & Disease Surveillance — Questions 1-8]
Q1: A researcher is investigating a potential outbreak of a novel respiratory virus in a swine
production facility. She decides to conduct a study where she enrolls 50 pigs with respiratory
signs and 50 healthy pigs from the same barn, then looks back at their feed records to compare
exposure to a new batch of feed supplement. Which type of study design is this?
A. Prospective Cohort Study
B. Randomized Controlled Trial
C. Retrospective Case-Control Study [CORRECT]
D. Cross-Sectional Study
Correct Answer: C
Rationale: This is a retrospective case-control study because the subjects are selected based on
their outcome status (diseased vs. healthy), and the investigator looks back in time to assess
previous exposures (feed records). Cohort studies (A) would group by exposure and follow for
outcomes. Cross-sectional studies (D) assess exposure and outcome at a single point in time.
This design is efficient for rare diseases or outbreak investigations where time is limited.
Q2: In a population of 1,000 dairy cattle, a diagnostic test with a Sensitivity of 95% and a
Specificity of 90% is used to screen for Johnes disease. If the true prevalence of Johnes disease
in this herd is 10%, what is the Positive Predictive Value (PPV) of this test?
A. 95%
B. 50%
C. 51.4% [CORRECT]
D. 90%
,2
Correct Answer: C
Rationale: To calculate PPV, one must use a 2x2 table. With 10% prevalence, there are 100 truly
diseased animals. The test identifies 95 of them (True Positives). Of the 900 non-diseased
animals, the test incorrectly identifies 10% (False Positives), which is 90 animals. PPV = TP /
(TP + FP) = 95 / (95 + 90) = 95/185 ≈ 51.4%. This demonstrates that even with good sensitivity
and specificity, low prevalence can result in a relatively low PPV, meaning positive results need
confirmation. Options A and D reflect the test characteristics, not the predictive value in this
specific context.
Q3: Which of the following best describes the "Herd Immunity Threshold" and its implication
for veterinary preventive medicine?
A. The total number of animals vaccinated in a herd, regardless of vaccine efficacy.
B. The point at which a disease is eradicated from a specific geographic region.
C. The proportion of a population that must be immune to an infectious disease, either through
vaccination or previous infections, to stop its spread. [CORRECT]
D. The level of maternal antibodies present in newborn calves that protect them for the first 6
months of life.
Correct Answer: C
Rationale: The herd immunity threshold (HIT) is the critical density of susceptible individuals
below which a disease cannot persist. When a sufficient proportion of the herd is immune (e.g.,
via vaccination), the effective reproduction number (R) drops below 1, protecting even
unvaccinated individuals. Option A ignores vaccine efficacy and distribution. Option B refers to
eradication status, which is a distinct epidemiologic concept. Option D describes passive
immunity, which is temporary and individual, not a population-level dynamic.
Q4: When evaluating surveillance data for a reportable animal disease, a "Sentinel" surveillance
system is utilized. What is the primary advantage of this approach?
A. It requires testing every single animal in the population.
B. It is less expensive and allows for early warning by monitoring specific high-risk groups or
locations.
, 3
C. It eliminates the need for laboratory confirmation. [CORRECT]
D. It provides a complete count of all cases, including subclinical infections.
Correct Answer: B
Sentinel surveillance involves monitoring a selected subset of the population (sentinels) that are
at high risk or highly visible. This is cost-effective and acts as an early warning system for
changes in disease patterns before they become widespread. Option A describes universal
screening. Option C is incorrect because laboratory confirmation is still a cornerstone of sentinel
programs. Option D is impossible for most surveillance systems as subclinical cases often go
undetected.
Q5: An epidemiologist observes that the incidence rate of Leptospirosis in dogs is higher in
households located near stagnant water bodies compared to households in urban areas. However,
upon closer analysis, households near water also tend to have lower vaccination rates and higher
populations of rodents. In this scenario, what is the role of "Proximity to Water"?
A. It is the sole cause of the disease.
B. It is a confounder.
C. It is likely a confounder or associated with the true exposure (rodents/lack of vaccination),
necessitating multivariate analysis to distinguish. [CORRECT]
D. It is an effect modifier.
Correct Answer: C
Confounding occurs when an outside variable is associated with both the exposure (living near
water) and the outcome (Leptospirosis) but is not on the causal pathway. Here, rodents and
vaccination rates are likely the more direct drivers of risk, but they correlate with where people
live. To assess the true independent risk of water proximity, the epidemiologist must adjust for
these other variables. Option A ignores multifactorial causation. Option D (effect modifier)
implies the risk changes based on the level of the variable, which is different from confounding.
Q6: In an outbreak of Avian Influenza, the "Epidemic Curve" (epi curve) shows a steep rise to a
peak followed by a rapid decline over a period of days. What pattern of transmission does this
shape suggest?
ACVPM Practice Test Actual Exam
2026/2027 – Complete Exam-Style Questions
with Detailed Rationales | 100% Verified |
Pass Guaranteed – A+ Graded
[SECTION 1: Epidemiology & Disease Surveillance — Questions 1-8]
Q1: A researcher is investigating a potential outbreak of a novel respiratory virus in a swine
production facility. She decides to conduct a study where she enrolls 50 pigs with respiratory
signs and 50 healthy pigs from the same barn, then looks back at their feed records to compare
exposure to a new batch of feed supplement. Which type of study design is this?
A. Prospective Cohort Study
B. Randomized Controlled Trial
C. Retrospective Case-Control Study [CORRECT]
D. Cross-Sectional Study
Correct Answer: C
Rationale: This is a retrospective case-control study because the subjects are selected based on
their outcome status (diseased vs. healthy), and the investigator looks back in time to assess
previous exposures (feed records). Cohort studies (A) would group by exposure and follow for
outcomes. Cross-sectional studies (D) assess exposure and outcome at a single point in time.
This design is efficient for rare diseases or outbreak investigations where time is limited.
Q2: In a population of 1,000 dairy cattle, a diagnostic test with a Sensitivity of 95% and a
Specificity of 90% is used to screen for Johnes disease. If the true prevalence of Johnes disease
in this herd is 10%, what is the Positive Predictive Value (PPV) of this test?
A. 95%
B. 50%
C. 51.4% [CORRECT]
D. 90%
,2
Correct Answer: C
Rationale: To calculate PPV, one must use a 2x2 table. With 10% prevalence, there are 100 truly
diseased animals. The test identifies 95 of them (True Positives). Of the 900 non-diseased
animals, the test incorrectly identifies 10% (False Positives), which is 90 animals. PPV = TP /
(TP + FP) = 95 / (95 + 90) = 95/185 ≈ 51.4%. This demonstrates that even with good sensitivity
and specificity, low prevalence can result in a relatively low PPV, meaning positive results need
confirmation. Options A and D reflect the test characteristics, not the predictive value in this
specific context.
Q3: Which of the following best describes the "Herd Immunity Threshold" and its implication
for veterinary preventive medicine?
A. The total number of animals vaccinated in a herd, regardless of vaccine efficacy.
B. The point at which a disease is eradicated from a specific geographic region.
C. The proportion of a population that must be immune to an infectious disease, either through
vaccination or previous infections, to stop its spread. [CORRECT]
D. The level of maternal antibodies present in newborn calves that protect them for the first 6
months of life.
Correct Answer: C
Rationale: The herd immunity threshold (HIT) is the critical density of susceptible individuals
below which a disease cannot persist. When a sufficient proportion of the herd is immune (e.g.,
via vaccination), the effective reproduction number (R) drops below 1, protecting even
unvaccinated individuals. Option A ignores vaccine efficacy and distribution. Option B refers to
eradication status, which is a distinct epidemiologic concept. Option D describes passive
immunity, which is temporary and individual, not a population-level dynamic.
Q4: When evaluating surveillance data for a reportable animal disease, a "Sentinel" surveillance
system is utilized. What is the primary advantage of this approach?
A. It requires testing every single animal in the population.
B. It is less expensive and allows for early warning by monitoring specific high-risk groups or
locations.
, 3
C. It eliminates the need for laboratory confirmation. [CORRECT]
D. It provides a complete count of all cases, including subclinical infections.
Correct Answer: B
Sentinel surveillance involves monitoring a selected subset of the population (sentinels) that are
at high risk or highly visible. This is cost-effective and acts as an early warning system for
changes in disease patterns before they become widespread. Option A describes universal
screening. Option C is incorrect because laboratory confirmation is still a cornerstone of sentinel
programs. Option D is impossible for most surveillance systems as subclinical cases often go
undetected.
Q5: An epidemiologist observes that the incidence rate of Leptospirosis in dogs is higher in
households located near stagnant water bodies compared to households in urban areas. However,
upon closer analysis, households near water also tend to have lower vaccination rates and higher
populations of rodents. In this scenario, what is the role of "Proximity to Water"?
A. It is the sole cause of the disease.
B. It is a confounder.
C. It is likely a confounder or associated with the true exposure (rodents/lack of vaccination),
necessitating multivariate analysis to distinguish. [CORRECT]
D. It is an effect modifier.
Correct Answer: C
Confounding occurs when an outside variable is associated with both the exposure (living near
water) and the outcome (Leptospirosis) but is not on the causal pathway. Here, rodents and
vaccination rates are likely the more direct drivers of risk, but they correlate with where people
live. To assess the true independent risk of water proximity, the epidemiologist must adjust for
these other variables. Option A ignores multifactorial causation. Option D (effect modifier)
implies the risk changes based on the level of the variable, which is different from confounding.
Q6: In an outbreak of Avian Influenza, the "Epidemic Curve" (epi curve) shows a steep rise to a
peak followed by a rapid decline over a period of days. What pattern of transmission does this
shape suggest?
