NR 503 EPIDEMIOLOGY MIDTERM EXAM
QUESTIONS & ANSWERS (GRADED A)
1. The population of a city on February 15, 2005, was 36,600. The city has a
passive surveillance system that collects hospital and private physician
reports of influenza cases every month. During the period between January
1 and April 1, 2005, 2,200 new cases of influenza occurred in the city. Of
these cases, 775 persons were ill with influenza according to surveillance
reports on April 1, 2005. The prevalence rate of active influenza as of April
1, 2005, was:
Answer: 20 per 1,000 population
2. The population of a city on February 15, 2005, was 36,600. The city has a
passive surveillance system that collects hospital and private physician
reports of influenza cases every month. During the period between January
1 and April 1, 2005, 2,200 new cases of influenza occurred in the city. Of
these cases, 775 persons were ill with influenza according to surveillance
reports on April 1, 2005. The monthly incidence rate of active cases of
influenza for the 3-month period was:
Answer: 20 per 1,000 population
3. What would be the effect on age-specific incidence rates of uterine cancer
if women with hysterectomies were excluded from the denominator of
incidence calculations assuming that most women who have had
hysterectomies are older than 50 years of age?
Answer: Rates would increase in women older than 50 years of age
but may decrease in younger women as they get older.
4. The ability of a single person to remain free of clinical illness following
exposure to an infectious agent is known as:
, Answer: Immunity
5. Which of the following reasons can explain why a person who did not
consume the infective food item got sick?
Answer: All of the above
6. Which of the food items (or combination of items) is most likely to be the
infective item(s)?
Answer: Ice cream only
7. The case-fatality rate associated with plague is lowest in which community?
Answer: Community C
8. The incidence and prevalence rates of a chronic childhood illness for a
specific community are given below.
Answer: The duration of disease is becoming longer.
9. The following table gives the mean annual age-specific mortality rates from
measles during the first 25 years of life in successive 5-year periods. You
may assume that the population is in a steady state (i.e., migrations out are
equal to migrations in).
Based on the information above, one may conclude:
Answer: Children ages 5 to 9 had the highest rate of death in all
periods
10.In a country with a population of 16 million people, 175,000 deaths
occurred during the year ending December 31, 2005. These included 45,000
deaths from tuberculosis (TB) in 135,000 persons who were sick with TB.
Assume that the population remained constant throughout the year. Not all
135,000 cases of TB were contracted during 2005. Which of the following
statements is true?
QUESTIONS & ANSWERS (GRADED A)
1. The population of a city on February 15, 2005, was 36,600. The city has a
passive surveillance system that collects hospital and private physician
reports of influenza cases every month. During the period between January
1 and April 1, 2005, 2,200 new cases of influenza occurred in the city. Of
these cases, 775 persons were ill with influenza according to surveillance
reports on April 1, 2005. The prevalence rate of active influenza as of April
1, 2005, was:
Answer: 20 per 1,000 population
2. The population of a city on February 15, 2005, was 36,600. The city has a
passive surveillance system that collects hospital and private physician
reports of influenza cases every month. During the period between January
1 and April 1, 2005, 2,200 new cases of influenza occurred in the city. Of
these cases, 775 persons were ill with influenza according to surveillance
reports on April 1, 2005. The monthly incidence rate of active cases of
influenza for the 3-month period was:
Answer: 20 per 1,000 population
3. What would be the effect on age-specific incidence rates of uterine cancer
if women with hysterectomies were excluded from the denominator of
incidence calculations assuming that most women who have had
hysterectomies are older than 50 years of age?
Answer: Rates would increase in women older than 50 years of age
but may decrease in younger women as they get older.
4. The ability of a single person to remain free of clinical illness following
exposure to an infectious agent is known as:
, Answer: Immunity
5. Which of the following reasons can explain why a person who did not
consume the infective food item got sick?
Answer: All of the above
6. Which of the food items (or combination of items) is most likely to be the
infective item(s)?
Answer: Ice cream only
7. The case-fatality rate associated with plague is lowest in which community?
Answer: Community C
8. The incidence and prevalence rates of a chronic childhood illness for a
specific community are given below.
Answer: The duration of disease is becoming longer.
9. The following table gives the mean annual age-specific mortality rates from
measles during the first 25 years of life in successive 5-year periods. You
may assume that the population is in a steady state (i.e., migrations out are
equal to migrations in).
Based on the information above, one may conclude:
Answer: Children ages 5 to 9 had the highest rate of death in all
periods
10.In a country with a population of 16 million people, 175,000 deaths
occurred during the year ending December 31, 2005. These included 45,000
deaths from tuberculosis (TB) in 135,000 persons who were sick with TB.
Assume that the population remained constant throughout the year. Not all
135,000 cases of TB were contracted during 2005. Which of the following
statements is true?
