Chapter.19 Epidemiology Test Questions & Answers

Nester’s Microbiology, 9e (Anderson)

Chapter 19 Epidemiology

1) Women died after childbirth of 

A) S. aureus intoxication.

B) toxic shock syndrome.

C) Klein's disease.

D) puerperal fever.

E) shock.

2) The doctor responsible for introducing the idea of hand washing before attending patients was

A) Klein.

B) Semmelweis.

C) Koch.

D) Pasteur.

E) Galen.

3) Diseases that can be transmitted from one person to another are termed

A) symptomatic.

B) clinical.

C) acute.

D) latent.

E) communicable.

4) The natural habitat of a pathogen is referred to as its

A) home.

B) reservoir.

C) primary inhabitance.

D) infectious site.

E) place.

5) The number of cases of a specific disease per one hundred people exposed is called the

A) attack rate.

B) index rate.

C) mortality rate.

D) obesity rate.

E) attack index.

6) The number of people in a defined population who die during a given period is called the

A) mortality rate.

B) morbidity rate.

C) attack rate.

D) incidence rate.

E) case rate.

7) Diseases constantly present in a population are called

A) epidemic.

B) chronic.

C) latent.

D) endemic.

E) prodromic.

8) An epidemic that spreads worldwide is called a(n)

A) epidemical.

B) endemic.

C) pandemic.

D) syndemic.

E) plague.

9) A cluster of cases in a specific population occurring in a brief period of time is called a(n)

A) outbreak.

B) endemic.

C) pandemic.

D) attack break.

E) mortality.

10) Apparently healthy people who may transmit a pathogen they harbor are called

A) vectors.

B) carriers.

C) fomites.

D) vehicles.

E) arthropods.

11) Gonorrhea is a disease that may be

A) zoonotic.

B) pandemic.

C) syndemic.

D) asymptomatic.

E) All of the answer choices are correct.

12) A dramatic increase in the incidence of a specific disease in a given population is referred to as a(n)

A) pandemic.

B) endemic.

C) epidemic.

D) mortality.

E) outburst.

13) Diseases that primarily exist in animals, but may be transmitted to humans are called

A) parasitic.

B) zoonotic.

C) symbiotic.

D) epidemic.

E) commensal.

14) The reservoir of infection for botulism and tetanus is

A) humans.

B) soil.

C) water.

D) animals.

E) soil AND water.

15) Which of the following is considered a zoonotic disease?

A) Measles

B) Typhoid

C) Common cold

D) Influenza

E) Plague

16) Vertical transmission involves

A) droplet transmission.

B) fomites.

C) pregnant woman to fetus.

D) pasteurization.

E) insect to human.

17) The single most important measure to prevent the spread of disease is

A) hand washing.

B) canning.

C) pasteurization.

D) home cooking.

E) antibiotics.

18) Inanimate objects capable of transferring infectious disease agents are

A) vectors.

B) fomites.

C) vehicles.

D) reservoirs.

E) arthropods.

19) Large respiratory droplets typically travel no farther from point of release than

A) 3 meters.

B) 5 meters.

C) 1 meter.

D) 20 meters.

E) 12 inches.

20) Important sources of contamination in crowded locations are

A) droplets of blood.

B) droplets of saliva or mucus.

C) restrooms.

D) kitchen surfaces.

E) All of the answer choices are correct.

21) Droplet nuclei typically travel no farther from point of release than

A) 3 meters.

B) 5 meters.

C) 1 meter.

D) 12 inches.

E) They are suspended indefinitely.

22) In order to prevent spread of microorganisms from the microbiology laboratory, the room air should be

A) under positive pressure AND filtered.

B) under negative pressure AND filtered.

C) under negative pressure, chilled, AND filtered.

D) under positive pressure, chilled, AND filtered.

E) under neutral pressure, chilled, AND filtered.

23) Which of the following is not a vector?

A) Fomite

B) Human

C) Fly

D) Flea

E) Fomite AND human

24) Which of the following is not a mechanical vector?

A) Fomite

B) Human

C) Fly

D) Flea

E) Fomite AND human

25) The amount of infecting agent received by susceptible individuals is called the 

A) exposure.

B) infectious number.

C) infectious dose.

D) infecting level.

E) infective exposure.

26) The period of time between exposure to an agent and the onset of disease signs and symptoms is called the

A) prodromal phase.

B) decline phase.

C) incubation period.

D) lag phase.

E) carrier phase.

27) When an infectious disease cannot spread in a population because it lacks a significant number of susceptible hosts, the phenomenon is referred to as

A) protected population.

B) active immunity.

C) passive immunity.

D) herd immunity.

E) protective immunity.

28) The immunity of some black Africans to malaria is probably due to their

A) general health.

B) genetic background.

C) cultural practices.

D) age.

E) All of the answer choices are correct.

29) The type of epidemiological study that determines the characteristics of the persons involved and the time and place of the outbreak is called a(n)

A) descriptive study.

B) inspection study.

C) cohortive study.

D) retrospective study.

E) cohesive study.

30) The first identified case in an outbreak is called the

A) starter case.

B) traceable case.

C) primary case.

D) index case.

E) initiator case.

31) If the number of people who become ill during an epidemic rises and falls rapidly, this is called a(n)

A) propagated epidemic.

B) promulgated epidemic.

C) common source epidemic.

D) index epidemic.

E) contagious epidemic.

32) If the number of people who become ill during an epidemic rises gradually, this is called a(n)

A) propagated epidemic.

B) promulgated epidemic.

C) common source epidemic.

D) index epidemic.

E) confluent epidemic.

33) An experimental study in which neither the doctor nor the patient knows who is getting the actual treatment is called a ________ study.

A) single-sided

B) double-sided

C) double-blind

D) double-barrier

E) test-sided

34) Because of the natural evolution of microorganisms, it is necessary to use techniques that allow distinguishing them at the level of

A) species.

B) genus.

C) family.

D) strain.

E) domain.

35) The publication of the CDC that reports new cases of reportable infectious diseases is titled

A) Morbidity and Mortality Weekly Report (MMWR).

B) State Health News Letter (SHNL).

C) Federal Report of Infectious Disease (FRID).

D) National Morbidity Weekly (NMW).

E) Monthly Death and Disease Report (MDDR).

36) The World Health Organization (WHO) is part of the

A) Food and Drug Administration.

B) Department of Health and Human Services.

C) Department of Human Resources.

D) United Nations.

E) North Atlantic Treaty Organization.

37) WHO has targeted for elimination of

A) polio.

B) dracunculiasis.

C) measles.

D) plague.

E) polio, dracunculiasis, AND measles.

38) So far, the only disease that has been globally eradicated is

A) polio.

B) smallpox.

C) measles.

D) diphtheria.

39) A new serotype of Vibrio cholerae, V. cholerae 0139, has picked up the ability to produce

A) pili.

B) flagella.

C) a capsule.

D) a toxin.

E) endotoxin.

40) Schistosomiasis has increased in areas where

A) snails have become a delicacy.

B) crayfish are eaten.

C) dams have been built.

D) swamps have been drained.

E) people fish for sport.

41) Approximately what percentage of hospitalized patients may develop a nosocomial infection?

A) 0%

B) 5%

C) 15%

D) 20%

E) 70%

42) An infection acquired during hospitalization is referred to as a(n) ________ infection.

A) antibiotic-induced

B) therapeutic

C) medication-stimulated

D) nosocomial

E) herd initiated

43) All of the following are commonly associated with nosocomial disease EXCEPT

A) Enterococcus species.

B) Clostridium difficile.

C) Pseudomonas species.

D) Staphylococcus aureus.

E) Clostridium botulinum.

44) Which of the following contributes to nosocomial disease?

A) Susceptible population

B) Hospital environment

C) Other patients

D) Patient's own normal microbiota

E) All of the choices are correct.

45) The member of the hospital staff who surveys the types and numbers of nosocomial infections is called the

A) head nurse.

B) infection control practitioner.

C) staff control.

D) attending physician.

E) external epidemiologist.

46) The guidelines designed for prevention of nosocomial disease during care of all patients is called

A) Standard Precautions.

B) Universal Disposables.

C) Disinfection Manifesto.

D) Asepsis Preference.

E) Hand Hygiene Precautions.

47) Transmission-Based Precautions

A) is an online informative course all health workers must take on an annual basis.

B) are guidelines from WHO for dealing with emerging infectious diseases.

C) are instructions on the care of all patients given to nurses at their place of employment.

D) are guidelines to use with patients infected with a highly transmissible or epidemiologically important pathogen.

E) are guidelines given to patients before they enter the hospital to educate them on HAIs.

48) Prevention of patient-to-personnel transmission of disease depends on limiting contact with

A) patients.

B) personnel.

C) administrators.

D) physicians.

E) body fluids.

49) Which of the following is recommended by the Standard Precautions guidelines?

A) Glove use AND hand washing

B) Hand washing AND a face shield

C) A face shield AND antibiotics

D) Antibiotic use AND glove use

E) Glove use, hand washing, AND a face shield

50) The threat of bioterrorism

A) is due largely to the ease of spread and severity of diseases AND has prompted WHO to prepare a readiness plan.

B) is due largely to the ease of spread and severity of diseases AND may include rarely seen infectious agents.

C) is exaggerated in light of the efficiency of our healthcare system AND has prompted WHO to prepare a readiness plan.

D) has prompted the CDC to prepare a readiness plan AND is due largely to the ease of spread and severity of diseases.

E) has prompted the WHO to prepare a readiness plan, may include rarely seen infectious agents, AND is due largely to the ease of spread and severity of diseases.

51) Generally, the smaller the infective dose, the lower the chance of disease.

52) A fly may serve as a mechanical vector.

53) The portal of entry typically has little effect on the course of a disease.

54) The very young and the elderly are more susceptible to infectious disease.

55) Diseases with long incubation periods are more likely to spread extensively.

56) A gradual rise in numbers during an epidemic indicates a common source epidemic.

57) Cross-sectional surveys are very useful in establishing cause of a disease.

58) A placebo is a mock drug.

59) In a double-blind test the treating physician knows who is getting the actual treatment.

60) Nosocomial infections are those acquired at a hospital.

61) Human population growth and expansion contribute to emergence of diseases.

62) Explain the most likely reason why smallpox was successfully eradicated but rabies probably never will be.

A) Smallpox was only found in humans; rabies is found in numerous animal reservoirs. We cannot reasonably eliminate rabies in all of the animal reservoirs that exist.

B) It was far easier to vaccinate the world population against smallpox than against rabies, due to the lower number of injections required for the smallpox vaccine. It becomes a compliance issue.

C) Since there are very few cases of rabies each year, there is little financial incentive to push health organizations to eradicate the illness through worldwide vaccination.

D) The symptoms of smallpox are easier to identify than the symptoms of rabies, so some carriers of rabies are not accurately diagnosed. This can lead to asymptomatic carriers present within the population of susceptible individuals, spreading the virus.

E) Smallpox was eradicated because anyone who got the disease died from it, so at some point there was no reservoir for the virus. 

63) Explain how the incubation period can influence the spread of an infectious agent.

A) Incubation period does not affect the spread of an infectious agent. An infectious carrier will only spread the illness when they are showing acute symptoms. As such, the length of incubation period is not important for spreading the illness.

B) Depending on the microbe and the illness, an asymptomatic carrier in the incubation period might be shedding infectious microbes to his/her surroundings. In such a case, a longer incubation period would lead to a greater spread of the disease as the carrier comes into contact with more individuals while he/she is generally appearing to be healthy.

C) A very short incubation period will place a patient into the highly infectious active disease state sooner. Since people avoid contact with actively ill individuals, a very short incubation period will always lead to a decrease in the spread of an infectious disease.

D) A very long incubation period will place a patient into the highly infectious active disease state later. Since people generally avoid contact with actively ill individuals, a very long incubation period will always lead to a decrease in the spread of an infectious disease.

E) A short incubation period leads to an increase in the spread of an infectious agent. This is because diseases with a short incubation period are always far more severe than those with a long incubation period, so the infectious agent is spread more vigorously.

64) Why is it important to include a placebo in a scientific study to assess the effectiveness of a drug?

A) It's actually unethical to include a placebo and it is usually not done. If you have a drug that you know to be effective, it's unethical to withhold that treatment from an ill patient.

B) A placebo-treated group will determine if the changes observed in the drug-treated illness group are due to a psychological effect rather than a physiologic/pharmacologic one.

C) It isn't scientifically important to include a placebo. A placebo simply helps investigators satisfy the legal requirements of the Food and Drug Administration in their testing process.

D) A placebo-treated group will determine if the changes observed in the illness in this non-treated group are due to a physiologic/pharmacologic effect rather than a psychological one.

E) Both groups of people are actually given the drug and a placebo. This is a way to ensure patient compliance, without which the study would not yield any useable information.

65) Which of the following is NOT a political/societal reason for a decrease in rates of childhood immunizations?

A) Distrust of the healthcare body administering the vaccinations.

B) Distrust of the government funding the vaccination process.

C) A lack of a proper "cold chain" for stable transport of vaccines into tropical areas.

D) Distrust of the scientific community advocating for administration of vaccines.

E) Lack of awareness of the seriousness of diseases such as pertussis.

66) Please identify the CORRECT statement regarding basic epidemiology concepts.

A) Contagious disease—an infectious disease that can not be transmitted from one host to another.

B) Attack rate—the number of susceptible people developing illness in a population exposed to an infectious agent.

C) Incidence—the total number of cases of a disease in a given population at any time or for a specific period.

D) Prevalence—the number of new cases of a disease in a population at risk during a specified time period.

E) Morbidity rate—the proportion of people diagnosed with a specific disease who die from that disease.

67) In 1918-1919, an influenza virus infected about 500 million people worldwide, killing at least 50 million of them. This disease is best described as a(n) ________.

A) epidemic

B) pandemic

C) outbreak

D) sporadic outbreak

E) endemic disease.

68) A picnic was attended by 1,000 people. Potato salad was served at the event. The next day, 140 people reported vomiting and diarrhea. What was the attack rate of this food-borne illness?

A) 1.4%

B) 14%

C) 140%

D) 10%

E) More information is needed.

69) A fly that walks on feces and picks up E. coli O157:H7 then lands on food and transfers the microorganisms, is considered a

A) mechanical vector.

B) biological vector.

C) mechanical OR biological vector.

D) fomite.

E) cross-contaminator.

70) Select the sequence that indicates the steps that occur in the chain of infection.

1. Transmission.

2. Susceptible host.

3. Reservoir of infectious agent.

4. Portal of exit.

5. Portal of entry.

A) 3, 4, 1, 5, 2

B) 2, 3, 5, 4, 1

C) 1, 2, 3, 4, 5

D) 5, 3, 1, 2, 4

E) 3, 2, 1, 5, 4

71) Which pathogen is INCORRECTLY matched with a portal of exit?

A) Influenza virus—respiratory droplets.

B) Vibrio cholerae—feces.

C) Mycobacterium tuberculosis—droplets of saliva and mucus.

D) Neisseria gonorrhoeae—urethral and vaginal secretions.

E) E. coli—urine.

72) Which of the statements about transmission of pathogens is TRUE?

A) Vertical transmission of a pathogen is from the environment to a person.

B) Horizontal transmission refers to spread of a pathogen from mother to fetus.

C) Sexual intercourse is an example of indirect contact.

D) Droplet transmission is a particularly important source of contamination in densely populated buildings such as schools.

E) Droplet nuclei are large drops of pathogen-containing fluid discharged by talking; they fall to the ground within a meter of the person.

73) All of the following is/are reservoirs of infection in a hospital setting EXCEPT

A) patient's normal microbiota.

B) other patients.

C) medical personnel.

D) visitors.

E) sterile surgical equipment.

74) Which of the following pathogens/diseases would be the easiest to eradicate?

A) A pathogen that only infects humans and rarely causes signs and symptoms. 

B) A pathogen that only infects humans and causes obvious signs and symptoms.

C) A pathogen that causes disease in both animals and humans.

D) A pathogen that mostly infects animals but also sometimes causes disease in humans.

E) A disease that is asymptomatic and is carried by a large number of people in a population.

75) Please select the FALSE statement.

A) A common source epidemic occurs when all of the cases result from exposure to a single source of the infectious agent.

B) A case-control study occurs when all of the cases result from exposure to a single source of the infectious agent.

C) The natural habitat of a pathogen is called the reservoir of infection.

D) Herd immunity can never be overcome by a pathogen.

E) Emerging infectious diseases are those that are novel or have recently increased in incidence.

76) Which of the following best defines an endemic disease?

A) It is a disease that has a much higher incidence than usual.

B) It is a disease that used to be common but is eradicated through vaccination programs.

C) It is a disease that is transmitted by an arthropod vector.

D) It is a disease that occurs naturally in animals but may spread to people.

E) It is a disease that is always present at some level in a population.

Your class decides to celebrate the last day of spring break by having a picnic. You arrange to meet at your local park and everyone agrees to bring a dish of food to the event. On the day, there is a wide variety of things to eat, but the snack that everyone agreed was the best was the hot chicken wings made by Paul. Almost everyone ate at least two to three wings. The picnic was a huge success.

The next morning you wake up feeling awful. You have a low grade fever and you have both vomiting and diarrhea. You call your friend Susan to tell her you won't make it to class that day and to please take good notes, which she promises to do. About 20 minutes later, Susan calls you back and tells you that three other people have also called her and are experiencing the same symptoms as you. You realize that you must have all eaten something at the picnic that is causing your illness. After finding out that none of the vegetarians or vegans in the class are ill, you figure out that it was likely a meat product.

77) In this case, the reservoir of infection was likely the

A) chicken wings.

B) Susan.

C) flatware used at the picnic.

D) river in the park.

E) mosquitoes.

78) The portal of entry of the pathogen causing illness in this case is the

A) skin.

B) large intestine.

C) nose.

D) mouth.

E) mucociliary escalator.

79) Some populations more than others are likely to be affected by a given pathogen. Many population characteristics influence the occurrence of disease. Which of the following MOST likely explains why some students at the picnic did not get ill?

A) Herd immunity, that protects non-immune people from an infectious agent—the agent cannot spread in a population because most potential hosts are immune. Most students were probably immune to the foodborne pathogen.

B) Age, because the immune system starts to weaken after childhood, and consequently people are vulnerable to certain diseases when they reach adulthood. The younger students in the group remained healthy.

C) Behavioral practices, that significantly influence the rate and type of disease transmission; in this case the vegetarians and vegans remained healthy, suggesting that not eating meat protected them from the pathogen.

D) Gender, because females are always more likely than males to acquire gastrointestinal diseases due to differences in their gut normal microbiota populations. The students who got ill were all female.

E) None of these factors explain the outcome of the picnic.

80) The situation described in this case study is an example of a(n)

A) propagated epidemic, because one student became ill, followed by others over several days.

B) common-source epidemic, because several students became ill in the same time frame.

C) propagated epidemic, because several students became ill in the same time frame.

D) epidemic, because one student became ill and then spread the causative organism to many others.

E) cohort study, because there was a group of students all affected by the same pathogen.

81) There were 27 students at the picnic, of which 18 developed illness. The attack rate was thus nearly 67%. What does this mean?

A) The attack rate describes the number of susceptible people who become ill in a population after exposure to an infectious agent, in this case 67%.

B) The attack rate is the number of new cases in a specific time period in a given population, in this case 27.

C) This describes the number of people in a defined population who die during a given period, in this case nearly 18%.

D) The attack rate is the total number of cases at any time or for a specific period in a given population, in this case 27.

E) It describes the situation in which a particular disease arises from several genera of a person's own normal microbiota, in this case 18.

You are a newly qualified RN and have just been employed at your first job at a state hospital. Before you start your work with patients, you are required to complete a refresher course on nosocomial infections. You are asked to watch a short video and are then asked a series of questions, which are given below. You are somewhat nervous but need not be because you understand the risks of these infections and you know how they can be avoided. You answer the questions are directed.

82) Nosocomial (or healthcare-associated) infections are infections that

A) people acquire while receiving treatment in a healthcare setting such as a hospital, therapy center, urgent care facility, or long-term care residence.

B) are caused by organisms that never cause disease in healthy people, but only in sick or immunocompromised people, such as those in the hospital.

C) that are novel or have recently increased in incidence, such as Ebola virus disease and Zika virus disease.

D) result as populations increase, and people move into areas where they are more likely to come into contact with reservoirs of disease.

E) follow the natural evolution of microbes that allows them to gain new characteristics such as the ability to produce a protective capsule.

83) The organisms that cause healthcare-associated infections can originate from a number of different sources, including other patients, the healthcare environment, healthcare workers, visitors, and the patient's own microbiota. Select the INCORRECT statement.

A) P. aeruginosa is resistant to many disinfectants and antimicrobial medications, and requires few nutrients, which enables it to multiply in environments containing little other than water.

B) A healthcare worker who is an asymptomatic carrier of a pathogen such as Staphylococcus aureus may inadvertently infect patients; sometimes personnel do not realize that they pose a risk to patients until they are implicated in an outbreak.

C) Nearly any invasive procedure can transmit organisms of a patient's normal microbiota to otherwise sterile body sites—for example, skin microbiota such as Staphylococcus epidermidis may gain access to the bloodstream.

D) Transmission of HAI-causing infectious agents may be direct through contact with others, including healthcare personnel. However, indirect transmission almost never occurs in hospitals because they are a sterile environment.

E) Healthcare personnel should routinely wash or disinfect their hands after touching one patient before going to the next. They should also wear gloves when they have contact with patient's blood, mucous membranes, broken skin, or body fluids. 

84) Which of the following would be indirect transmission of a pathogen in a healthcare facility?

A) Medical devices such as urinary catheters.

B) Inadequately sterilized instruments used in invasive procedures.

C) Inadequately sterilized instruments used in invasive procedures AND healthcare personnel who do not wash their hands properly.

D) Medical devices such as urinary catheters AND inadequately sterilized instruments used in invasive procedures.

E) Healthcare personnel who do not wash their hands adequately AND intravenous (IV) catheters colonized with normal skin microbiota.

85) Which of the following does NOT correctly describe a Standard Precaution?

A) Personal protective equipment (PPE) includes gloves, a gown, and sometimes mask, goggles, or a face shield.

B) Respiratory hygiene includes instructing symptomatic healthcare personnel to stay home from work for at least two weeks.

C) A patient who is at increased risk of acquiring infection or developing an adverse outcome following infection should be placed in a single-patient room.

D) Personnel should adhere to federal and state requirements for protection from exposure to bloodborne pathogens.

E) Medical personnel who are likely to have had contact with spores (such as those of Clostridium difficile) should wash their hands with soap and water.

86) Which of the following is a possible origin of the organisms that cause healthcare-associated infections?

A) The patient's normal microbiota

B) Other patients

C) Medical personnel

D) Healthcare environment

E) All of the answer choices are correct.